Competitive Programming

Methods to Solve (2000-present)

Use these filters to narrow down your next problem to solve:

OJ: , Topic: , Quality: , Difficulty:

You can now sort these problems based on Distinct ACcepted Users (DACU) column.
Generally, problems with high DACU are the easier problems.
Note that we only update DACU column manually when we first entered the hint (thus an outdated data).

Column Point is only used in Kattis (and simulated in LeetCode) online judge.

All OJ Problem Title CP4+5 Hint DACU Point
00414 Fetching from uHunt 2.2a, 1D Array, Medium get the longest stretch of Bs 0.0
00482 Fetching from uHunt 2.2a, 1D Array, Medium you may need to use a string tokenizer as the size of the array is not specified 0.0
00591 Fetching from uHunt 2.2a, 1D Array, Medium sum all items; get the average; sum the total absolute differences of each item from the average divided by two 0.0
10038 Fetching from uHunt 2.2a, 1D Array, Medium 1D Boolean flags to check [1..n-1]; also available at Kattis - jollyjumpers 0.0
10050 Fetching from uHunt 2.2a, 1D Array, Medium 1D boolean flag 0.0
11192 Fetching from uHunt 2.2a, 1D Array, Medium character array 0.0
11496 Fetching from uHunt 2.2a, 1D Array, Medium store data in 1D array; count the peaks 0.0
11608 Fetching from uHunt 2.2a, 1D Array, Medium use three arrays: created; required; available 0.0
11875 Fetching from uHunt 2.2a, 1D Array, Medium get median of a sorted input 0.0
12150 Fetching from uHunt 2.2a, 1D Array, Medium simple manipulation 0.0
12356 Fetching from uHunt 2.2a, 1D Array, Medium similar to deletion in doubly linked lists but we can still use a 1D array for the underlying data structure 0.0
12854 Fetching from uHunt 2.2a, 1D Array, Medium 1D array of size 5; trivial 0.0
12959 Fetching from uHunt 2.2a, 1D Array, Medium just go through the 1D array 0.0
12996 Fetching from uHunt 2.2a, 1D Array, Medium we need 1D array to store the number of N mango types first 0.0
13026 Fetching from uHunt 2.2a, 1D Array, Medium you have to store the N strings in an array first 0.0
13181 Fetching from uHunt 2.2a, 1D Array, Medium find the largest gap between two Xs; special corner cases at the two end points 0.0
baloni baloni 2.2a, 1D Array, Medium clever use of 1D histogram array to decompose the shots as per requirement 689 3.5
dihedralgroup dihedralgroup 2.2a, 1D Array, Medium check a circular array clockwise or counter-clockwise; modulo 159 2.5
downtime downtime 2.2a, 1D Array, Medium 1D array; use Fenwick Tree-like operation for Range Update Point Query 1068 3.2
erase erase 2.2a, 1D Array, Medium if N is odd, the second line has to be the inverse of the first; if N is even, both lines have to be the same 2166 1.6
fluortanten fluortanten 2.2a, 1D Array, Medium remove Bjorn first; then do O(n) pass to check where is Bjorn's optimal position 181 3.1
greedilyincreasing greedilyincreasing 2.2a, 1D Array, Medium just 1D array manipulation; this is not the DP-LIS problem 1151 1.9
jollyjumpers jollyjumpers 2.2a, 1D Array, Medium 1D Boolean flags to check [1..n-1]; also available at UVa 10038 - Jolly Jumpers 413 3.4
lc0088 to replace with LeetCode link soon... 2.2a, 1D Array, Medium do merge of Merge sort; top-interview-150 0 2.0
lc0163 to replace with LeetCode link soon... 2.2a, 1D Array, Medium PREMIUM - hint hidden 0 2.0
lc0189 to replace with LeetCode link soon... 2.2a, 1D Array, Medium simple if we can use additional O(n) space; top-100-liked; top-interview-150 0 4.0
lc0228 to replace with LeetCode link soon... 2.2a, 1D Array, Medium one pass; string formatting; top-interview-150 0 2.0
lc0605 to replace with LeetCode link soon... 2.2a, 1D Array, Medium tricky 1D array processing; leetcode-75 0 2.0
lc0941 to replace with LeetCode link soon... 2.2a, 1D Array, Medium check 1D array property 0 2.0
lc0985 to replace with LeetCode link soon... 2.2a, 1D Array, Medium sum all even integers first (sum_even); for each query, you can update sum_even in O(1) 0 4.0
lc1184 to replace with LeetCode link soon... 2.2a, 1D Array, Medium 1D circular array processing 0 2.0
lc1389 to replace with LeetCode link soon... 2.2a, 1D Array, Medium basic List ADT operations 0 2.0
lc1413 to replace with LeetCode link soon... 2.2a, 1D Array, Medium 1D array processing 0 2.0
lc1550 to replace with LeetCode link soon... 2.2a, 1D Array, Medium one pass; check three adjacent indices 0 2.0
lc1848 to replace with LeetCode link soon... 2.2a, 1D Array, Medium two passes: to the right and to the left 0 2.0
lc3069 to replace with LeetCode link soon... 2.2a, 1D Array, Medium use two arrays; do as asked 0 2.0
lc3131 to replace with LeetCode link soon... 2.2a, 1D Array, Medium find the difference of min integer in both arrays 0 2.0
lc3392 to replace with LeetCode link soon... 2.2a, 1D Array, Medium one pass through array as asked 0 2.0
lc3423 to replace with LeetCode link soon... 2.2a, 1D Array, Medium simple circular array processing 0 2.0
lc3452 to replace with LeetCode link soon... 2.2a, 1D Array, Medium just be careful with 1D array indexing 0 2.0
rankproblem rankproblem 2.2a, 1D Array, Medium list (array) manipulation problem 120 2.8
trackingshares trackingshares 2.2a, 1D Array, Medium keep track of the shares in small arrays and simulate 73 2.2
vaccineefficacy vaccineefficacy 2.2a, 1D Array, Medium use small arrays; just compute as described 102 2.6
00230 Fetching from uHunt 2.2c, 1D Array, Harder string parsing; maintain sorted books by author names then by title; the input size is small; we do not need balanced BS... 0.0
00394 Fetching from uHunt 2.2c, 1D Array, Harder any n-dimensional array is stored in computer memory as a single dimensional array; follow the problem description 0.0
00467 Fetching from uHunt 2.2c, 1D Array, Harder linear scan; 1D boolean flag 0.0
00665 Fetching from uHunt 2.2c, 1D Array, Harder use 1D boolean flags; each =; <; or > tells us an information; check if there is only one candidate false coin left at t... 0.0
00946 Fetching from uHunt 2.2c, 1D Array, Harder just 1D array manipulation; be careful with the special restriction 0.0
10978 Fetching from uHunt 2.2c, 1D Array, Harder 1D string array 0.0
11093 Fetching from uHunt 2.2c, 1D Array, Harder linear scan; circular array; a bit challenging 0.0
11222 Fetching from uHunt 2.2c, 1D Array, Harder use several 1D arrays 0.0
11850 Fetching from uHunt 2.2c, 1D Array, Harder for each integer location from 0 to 1322; can Brenda reach (anywhere within 200 miles of) any charging stations? 0.0
12662 Fetching from uHunt 2.2c, 1D Array, Harder 1D array manipulation; brute force 0.0
13048 Fetching from uHunt 2.2c, 1D Array, Harder use 1D Boolean array; simulate 0.0
astro astro 2.2c, 1D Array, Harder use large Boolean array 115 4.3
charged charged 2.2c, 1D Array, Harder convoluted problem statement; ignore E and F; for each cell, compute sum of Vs using rx/ry; convert the value of each ce... 61 1.8
crashingrobots crashingrobots 2.2c, 1D Array, Harder just simulate the x/y/direction of the N robots 107 4.6
divideby100 divideby100 2.2c, 1D Array, Harder big 1D character array processing; be careful 557 4.2
flippingpatties flippingpatties 2.2c, 1D Array, Harder use 1D int array of size 43 201; at each time t, we need one cook (hand) at time t-2d (to start), t-d (to flip), ... 116 2.4
inverteddeck inverteddeck 2.2c, 1D Array, Harder can we sort the array with just one contiguous swap?; compress duplicates; use sentinel so that we only check /&bsol... 203 3.7
keypad keypad 2.2c, 1D Array, Harder 2D array manipulation 200 3.3
lc0042 to replace with LeetCode link soon... 2.2c, 1D Array, Harder find index i with max h eight; process left/right of i separately; top-100-liked; top-interview-150 0 6.0
lc0075 to replace with LeetCode link soon... 2.2c, 1D Array, Harder Dutch national flag partitioning problem; O(n) solution; top-100-liked 0 4.0
lc0238 to replace with LeetCode link soon... 2.2c, 1D Array, Harder use prefix and suffix products; leetcode-75; top-100-liked; top-interview-150 0 4.0
lc0281 to replace with LeetCode link soon... 2.2c, 1D Array, Harder PREMIUM - hint hidden 0 4.0
lc0724 to replace with LeetCode link soon... 2.2c, 1D Array, Harder similar to Kattis - pivot; leetcode-75 0 2.0
lc1732 to replace with LeetCode link soon... 2.2c, 1D Array, Harder prefix sum; keep the max; leetcode-75 0 2.0
lc1869 to replace with LeetCode link soon... 2.2c, 1D Array, Harder split s using 0 as delimiter; take token with the max length; do the same but using 1 as delimiter; compare 0 2.0
lc1991 to replace with LeetCode link soon... 2.2c, 1D Array, Harder compute prefix and suffix; similar to LC 0724 0 2.0
lc2016 to replace with LeetCode link soon... 2.2c, 1D Array, Harder compute prefix minimum for O(n) solution; O(n^2) still pass 0 2.0
lc2574 to replace with LeetCode link soon... 2.2c, 1D Array, Harder compute prefix sum and suffix sum first 0 2.0
lc2996 to replace with LeetCode link soon... 2.2c, 1D Array, Harder non-standard 1D array processing 0 2.0
lc3010 to replace with LeetCode link soon... 2.2c, 1D Array, Harder take the first index and two other indices with minimum and second minimum values 0 2.0
mastermind mastermind 2.2c, 1D Array, Harder 1D array manipulation to count r and s 446 2.4
physicalmusic physicalmusic 2.2c, 1D Array, Harder a reading comprehension problem to come up with a simple algorithm to determine the answer 168 5.5
piperotation piperotation 2.2c, 1D Array, Harder use 1D Boolean array to check if cell (r, c) needs to be connected from the top (r-1) or left (c-1) and pass information... 50 2.6
pivot pivot 2.2c, 1D Array, Harder static range min/max query problem; special condition allows this problem to be solvable in O(n) using help of 1D arrays 1723 3.2
queens queens 2.2c, 1D Array, Harder simple N queens verifier program; use several 1D Boolean arrays to help do this check in O(N) 725 3.3
rockband rockband 2.2c, 1D Array, Harder interesting usage of 1D array to simplify the solution; a bit of sorting to arrange the output 194 3.9
traffic traffic 2.2c, 1D Array, Harder just simulate the movement of the car for 'longer than 10^6', analyze the required bound 233 4.1
upsanddownsofinvesting upsanddownsofinvesting 2.2c, 1D Array, Harder simplify by a factor of two by realizing that peaks and valleys are symmetrical 147 3.6
00541 Fetching from uHunt 2.2d, 2D Array, Medium count the number of 1s for each row/col; which must be even; if there is an error; see if the odd number of 1s appear on... 0.0
00585 Fetching from uHunt 2.2d, 2D Array, Medium recursive grammar check and output formatting 0.0
10703 Fetching from uHunt 2.2d, 2D Array, Medium use 2D boolean array of size 500*500 0.0
10920 Fetching from uHunt 2.2d, 2D Array, Medium simulate the process 0.0
11040 Fetching from uHunt 2.2d, 2D Array, Medium non trivial 2D array manipulation 0.0
11581 Fetching from uHunt 2.2d, 2D Array, Medium simulate the process 0.0
11835 Fetching from uHunt 2.2d, 2D Array, Medium do as asked 0.0
12187 Fetching from uHunt 2.2d, 2D Array, Medium simulate the process 0.0
12667 Fetching from uHunt 2.2d, 2D Array, Medium use both 1D and 2D arrays to store submission status 0.0
12981 Fetching from uHunt 2.2d, 2D Array, Medium small 2x2 matrix rotation 0.0
compromise compromise 2.2d, 2D Array, Medium 2D array manipulation; take the majority bits of each column; output either 0 or 1 for ties 363 2.2
epigdanceoff epigdanceoff 2.2d, 2D Array, Medium count number of CCs on 2D grid; simpler solution exists: count the number of blank columns plus one 505 1.9
fallingsnow2 fallingsnow2 2.2d, 2D Array, Medium count frequency of 'S' on each column 447 1.4
fastestavailableroute fastestavailableroute 2.2d, 2D Array, Medium count the number of dots in a 2D grid; scale up by a factor of s 126 2.5
flowshop flowshop 2.2d, 2D Array, Medium interesting 2D array manipulation 392 2.5
guesswho guesswho 2.2d, 2D Array, Medium 2D and 1D array; simulate and eliminate impossible candidates 197 1.6
imageprocessing imageprocessing 2.2d, 2D Array, Medium interesting 2D array manipulation 344 2.1
laegdyfirlandinu laegdyfirlandinu 2.2d, 2D Array, Medium easy 2D array check 208 1.6
laptopstickers laptopstickers 2.2d, 2D Array, Medium 2D array manipulation 318 2.5
lc0027 to replace with LeetCode link soon... 2.2d, 2D Array, Medium use Partition algorithm (two pointers) for in-place solution; top-interview-150 0 2.0
lc0251 to replace with LeetCode link soon... 2.2d, 2D Array, Medium PREMIUM - hint hidden 0 4.0
lc0422 to replace with LeetCode link soon... 2.2d, 2D Array, Medium PREMIUM - hint hidden 0 2.0
lc0566 to replace with LeetCode link soon... 2.2d, 2D Array, Medium 2D and possibly 1D matrix manipulation 0 2.0
lc0766 to replace with LeetCode link soon... 2.2d, 2D Array, Medium 2D matrix diagonal checks 0 2.0
lc0883 to replace with LeetCode link soon... 2.2d, 2D Array, Medium 2D matrix processing 0 2.0
lc1252 to replace with LeetCode link soon... 2.2d, 2D Array, Medium 2D matrix processing 0 2.0
lc1351 to replace with LeetCode link soon... 2.2d, 2D Array, Medium go row by row; right to left, O(m+n) 0 2.0
lc2022 to replace with LeetCode link soon... 2.2d, 2D Array, Medium simple 1D to 2D matrix conversion 0 2.0
lc2103 to replace with LeetCode link soon... 2.2d, 2D Array, Medium 3 colours; 10 rods; 2D Boolean matrix 0 2.0
lc2133 to replace with LeetCode link soon... 2.2d, 2D Array, Medium check if each row and col of a square matrix contains 1 to n 0 2.0
lc2319 to replace with LeetCode link soon... 2.2d, 2D Array, Medium 2D matrix property check 0 2.0
lc2639 to replace with LeetCode link soon... 2.2d, 2D Array, Medium 2D array and string length processing 0 2.0
lc3142 to replace with LeetCode link soon... 2.2d, 2D Array, Medium 2D matrix processing 0 2.0
meddelande meddelande 2.2d, 2D Array, Medium simple 2D array traversal; row major; skip '.' 1724 1.4
moderatepace moderatepace 2.2d, 2D Array, Medium sort each column; take the middle one 272 1.6
mylla2 mylla2 2.2d, 2D Array, Medium simple 3x3 grid manipulation 247 1.6
nineknights nineknights 2.2d, 2D Array, Medium 2D array checks; 8 directions 881 1.9
patchwork patchwork 2.2d, 2D Array, Medium tedious 2D grid manipulation 109 2.0
prjonamynstur prjonamynstur 2.2d, 2D Array, Medium process-2d-grid-on-the-fly 395 1.5
rulen rulen 2.2d, 2D Array, Medium bitmask application; follow the instructions 59 2.9
starbattles1 starbattles1 2.2d, 2D Array, Medium simple 2D array checks; use delta row/col technique to simplify the implementation 239 2.8
thisaintyourgrandpascheckerboard thisaintyourgrandpascheckerboard 2.2d, 2D Array, Medium simple 2D array manipulation 578 1.6
vemvinner vemvinner 2.2d, 2D Array, Medium small 3x3 array checks 408 2.1
00101 Fetching from uHunt 2.2e, 2D Array, Harder stack-like simulation; but we need to access the content of each stack too; so it is better to use 2D array 0.0
00434 Fetching from uHunt 2.2e, 2D Array, Harder a kind of visibility problem in geometry; solvable with using 2D array manipulation 0.0
00466 Fetching from uHunt 2.2e, 2D Array, Harder core functions: rotate and reflect 0.0
00512 Fetching from uHunt 2.2e, 2D Array, Harder apply all rows/columns modifications in descending order; for each query; report the new position of the cell or report ... 0.0
00707 Fetching from uHunt 2.2e, 2D Array, Harder this requires 3D array; but as there is no such category; it is classified here 0.0
10016 Fetching from uHunt 2.2e, 2D Array, Harder tedious 0.0
10855 Fetching from uHunt 2.2e, 2D Array, Harder string array; 90 degrees clockwise rotation 0.0
11360 Fetching from uHunt 2.2e, 2D Array, Harder do as asked 0.0
12291 Fetching from uHunt 2.2e, 2D Array, Harder do as asked; a bit tedious 0.0
12398 Fetching from uHunt 2.2e, 2D Array, Harder simulate backwards; do not forget to mod 10 0.0
2048 2048 2.2e, 2D Array, Harder just a 2D array manipulation problem; utilize symmetry using 90 degrees rotation(s) to reduce 4 cases into 1 3150 2.1
apples apples 2.2e, 2D Array, Harder 2D array manipulation; gravity simulation 439 3.6
falcondive falcondive 2.2e, 2D Array, Harder 2D array manipulation; translation vector of the Falcon 64 2.8
flagquiz flagquiz 2.2e, 2D Array, Harder array of array of strings; be careful; duplicates may exists 167 3.7
funhouse funhouse 2.2e, 2D Array, Harder 2D array manipulation; note the direction update 700 2.0
huntthewumpus huntthewumpus 2.2e, 2D Array, Harder tedious 2D array simulation 215 2.2
lc0048 to replace with LeetCode link soon... 2.2e, 2D Array, Harder rotate a 2D matrix; be careful; top-100-liked; top-interview-150 0 4.0
lc0054 to replace with LeetCode link soon... 2.2e, 2D Array, Harder heavy 2D matrix indexing; use dr/dc technique; programming-skills; top-100-liked; top-interview-150 0 4.0
lc0073 to replace with LeetCode link soon... 2.2e, 2D Array, Harder three mxn passes to identify and later process those rows/cols; programming-skills; top-100-liked; top-interview-150 0 4.0
lc0240 to replace with LeetCode link soon... 2.2e, 2D Array, Harder utilize the special property; start at top-left; top-100-liked 0 4.0
lc0289 to replace with LeetCode link soon... 2.2e, 2D Array, Harder tedious 2D grid manipulation; top-interview-150 0 4.0
lc0311 to replace with LeetCode link soon... 2.2e, 2D Array, Harder PREMIUM - hint hidden 0 4.0
lc0661 to replace with LeetCode link soon... 2.2e, 2D Array, Harder 2D matrix processing; check up to 8 neighbors 0 2.0
lc0861 to replace with LeetCode link soon... 2.2e, 2D Array, Harder process row and col separately; row: prioritize values; col: prioritize on bits 0 4.0
lc1380 to replace with LeetCode link soon... 2.2e, 2D Array, Harder compute the min of each row and max of each col first; then another O(mn) pass 0 2.0
lc2373 to replace with LeetCode link soon... 2.2e, 2D Array, Harder 2D matrix processing; 4-nested loops 0 2.0
lc2946 to replace with LeetCode link soon... 2.2e, 2D Array, Harder 2D matrix processing; 3-nested loops 0 2.0
prva prva 2.2e, 2D Array, Harder 2D array manipulation; check vertically and horizontally 756 1.7
rings2 rings2 2.2e, 2D Array, Harder more challenging 2D array manipulation; special output formatting style 385 3.8
tetris tetris 2.2e, 2D Array, Harder actually 3D pattern array to simulate various shape positions 322 1.8
waterworld waterworld 2.2e, 2D Array, Harder reading comprehension problem; compute average of a 2D array 68 2.2
00400 Fetching from uHunt 2.2f, Sorting, Easier this command is very frequently used in UNIX 0.0
00855 Fetching from uHunt 2.2f, Sorting, Easier sort; median 0.0
10107 Fetching from uHunt 2.2f, Sorting, Easier find median of a growing/dynamic list of integers; we can use multiple calls of nth_element in algorithm 0.0
10880 Fetching from uHunt 2.2f, Sorting, Easier use sort 0.0
10905 Fetching from uHunt 2.2f, Sorting, Easier modified comparison function; use sort 0.0
11039 Fetching from uHunt 2.2f, Sorting, Easier use sort then count different signs 0.0
11588 Fetching from uHunt 2.2f, Sorting, Easier sort simplifies the problem 0.0
11777 Fetching from uHunt 2.2f, Sorting, Easier sort simplifies the problem 0.0
11824 Fetching from uHunt 2.2f, Sorting, Easier sort simplifies the problem 0.0
12071 Fetching from uHunt 2.2f, Sorting, Easier reading comprehension; sort the input; compute something 0.0
12541 Fetching from uHunt 2.2f, Sorting, Easier LA 6148 - HatYai12; sort; youngest + oldest 0.0
12709 Fetching from uHunt 2.2f, Sorting, Easier LA 6650 - Dhaka13; although the problem has a complicated story; it has a very easy solution with sort routine 0.0
12861 Fetching from uHunt 2.2f, Sorting, Easier sort the timezones first and try adjacent pairings (two possibilities) 0.0
13113 Fetching from uHunt 2.2f, Sorting, Easier count the votes; sort; pick the top 2 0.0
basicprogramming2 basicprogramming2 2.2f, Sorting, Easier a nice problem about basic sorting applications 189 3.4
classfieldtrip classfieldtrip 2.2f, Sorting, Easier just sort the characters 1019 1.3
closingtheloop closingtheloop 2.2f, Sorting, Easier sort first 1415 1.6
cups cups 2.2f, Sorting, Easier a bit of string parsing; sort 2987 1.5
ferskastajarmid ferskastajarmid 2.2f, Sorting, Easier sort by controversiality*coolness (down); if tie, by alphabetical order 330 1.9
height height 2.2f, Sorting, Easier insertion sort simulation 899 2.0
judging judging 2.2f, Sorting, Easier sort DOM judge and Kattis outputs; then do the O(n) merge procedure of mergesort to count common outputs 1183 2.5
lc0004 to replace with LeetCode link soon... 2.2f, Sorting, Easier not-intended solution: sort in O(n log n) and report median; top-100-liked; top-interview-150 0 6.0
lc0217 to replace with LeetCode link soon... 2.2f, Sorting, Easier sort; check adjacent integers 0 2.0
lc0252 to replace with LeetCode link soon... 2.2f, Sorting, Easier PREMIUM - hint hidden 0 2.0
lc0268 to replace with LeetCode link soon... 2.2f, Sorting, Easier sort nums; find first i != nums[i] 0 2.0
lc0350 to replace with LeetCode link soon... 2.2f, Sorting, Easier modification of merge of Merge sort 0 2.0
lc0414 to replace with LeetCode link soon... 2.2f, Sorting, Easier sort; remove duplicates; special cases for len 1 or 2 0 2.0
lc0905 to replace with LeetCode link soon... 2.2f, Sorting, Easier custom comparison function; prioritize evens first 0 2.0
lc0977 to replace with LeetCode link soon... 2.2f, Sorting, Easier square all integers; sort again 0 2.0
lc1030 to replace with LeetCode link soon... 2.2f, Sorting, Easier sort by (Manhattan distance, r, c) 0 2.0
lc1051 to replace with LeetCode link soon... 2.2f, Sorting, Easier compare each element of heights with its sorted counterpart 0 2.0
lc1200 to replace with LeetCode link soon... 2.2f, Sorting, Easier sort arr to achieve min abs diff of adjacent integers 0 2.0
lc1337 to replace with LeetCode link soon... 2.2f, Sorting, Easier sort matrix rows by the sum of each row 0 2.0
lc1464 to replace with LeetCode link soon... 2.2f, Sorting, Easier sort; use the largest two 0 2.0
lc1657 to replace with LeetCode link soon... 2.2f, Sorting, Easier check if set of chars and its sorted frequency signatures are the same; leetcode-75 0 4.0
lc2089 to replace with LeetCode link soon... 2.2f, Sorting, Easier sort; do as asked 0 2.0
lc2164 to replace with LeetCode link soon... 2.2f, Sorting, Easier sort; custom rule 0 2.0
lc2733 to replace with LeetCode link soon... 2.2f, Sorting, Easier -1 for length 1 or 2; for length 3 or more; sort and report any index in [1..n-2] 0 2.0
lc2974 to replace with LeetCode link soon... 2.2f, Sorting, Easier sort; reverse each pair 0 2.0
magictrick magictrick 2.2f, Sorting, Easier can if all chars are unique or cannot otherwise; either sort s then check adjacent characters or use set to eliminate du... 1605 1.3
mjehuric mjehuric 2.2f, Sorting, Easier a direct simulation of a bubble sort algorithm 1349 1.6
musicaltrees musicaltrees 2.2f, Sorting, Easier sort p and t; then just simulate as asked with Boolean array 23 2.8
nothanks nothanks 2.2f, Sorting, Easier sort; then linear pass to check adjacent sorted elements 441 2.4
sidewayssorting sidewayssorting 2.2f, Sorting, Easier stable_sort or sort multi-fields of columns of a 2D array; ignore case 857 2.0
stokigalistor stokigalistor 2.2f, Sorting, Easier compare original list with its sorted version 537 2.2
lc0219 to replace with LeetCode link soon... 2.2g, Sorting, Simple Greedy sort (keep the original indices as pair (v, i)); check successive elements; top-interview-150 0 2.0
lc1502 to replace with LeetCode link soon... 2.2g, Sorting, Simple Greedy sort; check gap of successive elements; programming-skills 0 2.0
lc1637 to replace with LeetCode link soon... 2.2g, Sorting, Simple Greedy sort; remove duplicate x-s; check successive elements 0 2.0
lc1984 to replace with LeetCode link soon... 2.2g, Sorting, Simple Greedy sort; check elements that are k indices apart 0 2.0
lc2231 to replace with LeetCode link soon... 2.2g, Sorting, Simple Greedy sort even and odd digits separately; construct the largest number 0 2.0
lc2342 to replace with LeetCode link soon... 2.2g, Sorting, Simple Greedy sum-of-digits function; sort by (sod(n), n); check successive elements 0 4.0
lc2395 to replace with LeetCode link soon... 2.2g, Sorting, Simple Greedy sort the sum of all subarrays of size 2; check adjacent entries 0 2.0
lc2465 to replace with LeetCode link soon... 2.2g, Sorting, Simple Greedy sort; two pointers: smallest and largest 0 2.0
lc2500 to replace with LeetCode link soon... 2.2g, Sorting, Simple Greedy sort each row; process per column 0 2.0
00123 Fetching from uHunt 2.2h, Sorting, Harder modified comparison function; use sort 0.0
00450 Fetching from uHunt 2.2h, Sorting, Harder tedious sorting problem 0.0
00790 Fetching from uHunt 2.2h, Sorting, Harder multi-fields sorting; use sort; similar to UVa 10258 0.0
01610 Fetching from uHunt 2.2h, Sorting, Harder LA 6196 - MidAtlanticUSA12; median 0.0
10194 Fetching from uHunt 2.2h, Sorting, Harder multi-fields sorting; use sort 0.0
10258 Fetching from uHunt 2.2h, Sorting, Harder multi-fields sorting; use sort; similar to UVa 00790 0.0
10698 Fetching from uHunt 2.2h, Sorting, Harder multi-fields sorting; use sort 0.0
11300 Fetching from uHunt 2.2h, Sorting, Harder use sort; involving the median 0.0
11321 Fetching from uHunt 2.2h, Sorting, Harder be careful with negative mod! 0.0
12269 Fetching from uHunt 2.2h, Sorting, Harder sort and check if Guido covers all land (end-to-end and side-to-side); also available at Kattis - lawnmower 0.0
addemup addemup 2.2h, Sorting, Harder create a helper function to read digits upside down; add all possibilities; sort; then use fast O(n) target pair solutio... 338 4.4
booking booking 2.2h, Sorting, Harder 2 events per booking (need room and release room); convert to minutes; be careful of leap year on 2016; sort the events;... 164 5.4
chartingprogress chartingprogress 2.2h, Sorting, Harder sort using modified comparison function (by column); transpose the input 757 2.2
classy classy 2.2h, Sorting, Harder sort using modified comparison function; a bit of string parsing/tokenization 1633 4.5
dirtydriving dirtydriving 2.2h, Sorting, Harder sort; find max - derive the formula; reading comprehension problem 279 2.1
dyslectionary dyslectionary 2.2h, Sorting, Harder sort the reverse of original string; output formatting 775 3.4
gearchanging gearchanging 2.2h, Sorting, Harder generate all O(N*M) possible gear ratios; sort; check consecutive ratios (it is ok to have duplicates) 161 3.2
includescoring includescoring 2.2h, Sorting, Harder sort; custom comparison function, tedious 342 3.7
lawnmower lawnmower 2.2h, Sorting, Harder sort and check if Guido covers all land (end-to-end and side-to-side); also available at UVa 12269 - Land Mower 448 2.1
lc0001 to replace with LeetCode link soon... 2.2h, Sorting, Harder classic; O(n log n) solution: sort + two pointers; or hashing; top-100-liked; top-interview-150 0 2.0
lc0041 to replace with LeetCode link soon... 2.2h, Sorting, Harder O(n log n) solution; sort first; case analysis; top-100-liked 0 6.0
lc0280 to replace with LeetCode link soon... 2.2h, Sorting, Harder PREMIUM - hint hidden 0 4.0
lc0581 to replace with LeetCode link soon... 2.2h, Sorting, Harder there are O(n log n) easy sorting vs O(n) clever linear pass solutions 0 4.0
lc1356 to replace with LeetCode link soon... 2.2h, Sorting, Harder transform arr[i] into tuple (bitcount of arr[i], arr[i]); sort; output the second field 0 2.0
lc1451 to replace with LeetCode link soon... 2.2h, Sorting, Harder stable sort by (len(w), w) 0 4.0
lc1460 to replace with LeetCode link soon... 2.2h, Sorting, Harder check if the sorted versions of target and arr are equal 0 2.0
lc2418 to replace with LeetCode link soon... 2.2h, Sorting, Harder sorting with custom comparison function 0 2.0
lc2545 to replace with LeetCode link soon... 2.2h, Sorting, Harder sort a 2D matrix as asked 0 4.0
lc2785 to replace with LeetCode link soon... 2.2h, Sorting, Harder separate vowels and consonants; only sort the vowels 0 4.0
lc3194 to replace with LeetCode link soon... 2.2h, Sorting, Harder sort; use two pointers on extreme ends and move inside 0 2.0
lc3446 to replace with LeetCode link soon... 2.2h, Sorting, Harder just sorting; but on diagonals of 2D grid (two cases) 0 4.0
longswaps longswaps 2.2h, Sorting, Harder observation: if k ≤ n/2, output 'Yes'; otherwise the middle chars at s[n-k..k-1] cannot move; sort s and compare the ... 172 3.3
musicyourway musicyourway 2.2h, Sorting, Harder stable_sort; custom comparison function 404 2.4
sortofsorting sortofsorting 2.2h, Sorting, Harder stable_sort or sort multi-fields 2667 2.2
statues statues 2.2h, Sorting, Harder sort distinct statue heights; test all 4 possible diagonal placements, pick the min 106 2.8
zipfsong zipfsong 2.2h, Sorting, Harder sort; custom comparison function; zipf law 209 4.5
00299 Fetching from uHunt 2.2i, Special Sorting can use O(n^2) bubble sort 0.0
00612 Fetching from uHunt 2.2i, Special Sorting needs O(n^2) stable_sort 0.0
10327 Fetching from uHunt 2.2i, Special Sorting solvable with O(n^2) bubble sort 0.0
10810 Fetching from uHunt 2.2i, Special Sorting requires O(n log n) merge sort; also available at Kattis - ultraquicksort 0.0
11462 Fetching from uHunt 2.2i, Special Sorting standard Counting Sort problem 0.0
11495 Fetching from uHunt 2.2i, Special Sorting requires O(n log n) merge sort 0.0
11858 Fetching from uHunt 2.2i, Special Sorting requires O(n log n) merge sort; 64-bit integer; also available at Kattis - froshweek 0.0
13212 Fetching from uHunt 2.2i, Special Sorting requires O(n log n) merge sort 0.0
bread bread 2.2i, Special Sorting inversion count; hard to derive 249 5.0
excursion excursion 2.2i, Special Sorting inversion index; requires O(n log n) merge sort 387 4.3
froshweek froshweek 2.2i, Special Sorting requires O(n log n) merge sort; 64-bit integer; also available at UVa 11858 - Frosh Week 694 5.6
gamenight gamenight 2.2i, Special Sorting Counting Sort is a subproblem; count frequency of A/B/Cs; complete search AA..ABB..BCC..C or AA..ACC..CBB..B 70 2.8
lc1122 to replace with LeetCode link soon... 2.2i, Special Sorting counting sort variant using arr2 order 0 2.0
lc2717 to replace with LeetCode link soon... 2.2i, Special Sorting two passes of bubble sort; one to the right; one to the left 0 2.0
mali mali 2.2i, Special Sorting Counting Sort two arrays; greedy matching largest+smallest at that point 97 5.1
sort sort 2.2i, Special Sorting Counting Sort variant 318 2.3
ultraquicksort ultraquicksort 2.2i, Special Sorting requires O(n log n) merge sort; also available at UVa 10810 - Ultra Quicksort 180 5.2
00594 Fetching from uHunt 2.2j, Bit Manipulation manipulate bit string with bitset 0.0
00700 Fetching from uHunt 2.2j, Bit Manipulation can be solved with bitset 0.0
01241 Fetching from uHunt 2.2j, Bit Manipulation LA 4147 - Jakarta08; easy 0.0
10264 Fetching from uHunt 2.2j, Bit Manipulation heavy bitmask manipulation 0.0
10469 Fetching from uHunt 2.2j, Bit Manipulation super simple if you use xor 0.0
11173 Fetching from uHunt 2.2j, Bit Manipulation Divide and Conquer pattern or one liner bit manipulation 0.0
11760 Fetching from uHunt 2.2j, Bit Manipulation separate row col checks; use two bitsets 0.0
11926 Fetching from uHunt 2.2j, Bit Manipulation use 1M bitset to check if a slot is free 0.0
11933 Fetching from uHunt 2.2j, Bit Manipulation simple bit exercise 0.0
12571 Fetching from uHunt 2.2j, Bit Manipulation precalculate AND operations 0.0
12720 Fetching from uHunt 2.2j, Bit Manipulation observe the pattern in this binary to decimal conversion variant; involves modulo arithmetic 0.0
bitbybit bitbybit 2.2j, Bit Manipulation be very careful with and + or corner cases 955 2.9
bits bits 2.2j, Bit Manipulation use GNU C++ __builtin_popcount 1066 2.6
deathstar deathstar 2.2j, Bit Manipulation can be solved with bit manipulation 415 2.0
hypercube hypercube 2.2j, Bit Manipulation given a gray code; we can binary search its index: upper half/first digit 0 and bottom half/first digit 1 376 3.0
iboard iboard 2.2j, Bit Manipulation simulation; LSB to MSB; all ASCII values are 7-bits; we may need to add leading zeroes 363 2.3
lc0136 to replace with LeetCode link soon... 2.2j, Bit Manipulation XOR all integers; leetcode-75; top-100-liked; top-interview-150 0 2.0
lc0191 to replace with LeetCode link soon... 2.2j, Bit Manipulation bit_count; top-interview-150 0 2.0
lc0201 to replace with LeetCode link soon... 2.2j, Bit Manipulation hint: use LSOne; top-interview-150 0 4.0
lc0338 to replace with LeetCode link soon... 2.2j, Bit Manipulation bit_count; trivial; leetcode-75 0 2.0
lc0461 to replace with LeetCode link soon... 2.2j, Bit Manipulation bit_count of x^y 0 2.0
lc0476 to replace with LeetCode link soon... 2.2j, Bit Manipulation same as LC1009 0 2.0
lc0762 to replace with LeetCode link soon... 2.2j, Bit Manipulation check if bit_count in [2, 3, 5, 7, 11, 13, 17, 19] 0 2.0
lc1009 to replace with LeetCode link soon... 2.2j, Bit Manipulation XOR x with (11..1) 0 2.0
lc1318 to replace with LeetCode link soon... 2.2j, Bit Manipulation check all 31 bits; a few sub-cases per bit; leetcode-75 0 4.0
lc1486 to replace with LeetCode link soon... 2.2j, Bit Manipulation generate nums as asked, then XOR all its elements 0 2.0
lc2220 to replace with LeetCode link soon... 2.2j, Bit Manipulation xor and bit_count 0 2.0
lc2859 to replace with LeetCode link soon... 2.2j, Bit Manipulation use bit_count to identify Integers with k set bits 0 2.0
lc3226 to replace with LeetCode link soon... 2.2j, Bit Manipulation variant of Leetcode 2220; manual check this time 0 2.0
lc3370 to replace with LeetCode link soon... 2.2j, Bit Manipulation try all 2^i-1 for i in [0..10] 0 2.0
snappereasy snappereasy 2.2j, Bit Manipulation see Kattis - snapperhard 424 2.7
snapperhard snapperhard 2.2j, Bit Manipulation bit manipulation; find the pattern; the easier version is also available at Kattis - snappereasy 501 2.3
tictacstate tictacstate 2.2j, Bit Manipulation convert the octal state into 3x3 Tic-Tac-Toe state and decide the game's outcome; the 18-th bit is not used 403 2.5
zebrasocelots zebrasocelots 2.2j, Bit Manipulation zebra is 1; ocelot is 0; simulation of long long 563 3.2
00424 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger addition 0.0
00465 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger add/multiply; compare with 2^31-1$ 0.0
00619 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger 0.0
00713 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger StringBuffer reverse() 0.0
00748 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger exponentiation 0.0
01226 Fetching from uHunt 2.2k, Big Integer, Easier LA 3997 - Danang07; mod operation 0.0
01647 Fetching from uHunt 2.2k, Big Integer, Easier find the simple pattern first using brute force; then precompute the answers using BigInteger 0.0
10013 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger addition 0.0
10083 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger number theory 0.0
10106 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger multiplication 0.0
10198 Fetching from uHunt 2.2k, Big Integer, Easier recurrences; BigInteger 0.0
10430 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger; derive formula first 0.0
10433 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger: pow; substract; mod 0.0
10464 Fetching from uHunt 2.2k, Big Integer, Easier Java BigDecimal class 0.0
10494 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger division 0.0
10519 Fetching from uHunt 2.2k, Big Integer, Easier recurrences; BigInteger 0.0
10523 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger addition; multiplication; and power 0.0
10669 Fetching from uHunt 2.2k, Big Integer, Easier Big Integer is for 3^n; binary rep of set; also available at Kattis - threepowers 0.0
10925 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger addition and division 0.0
10992 Fetching from uHunt 2.2k, Big Integer, Easier input size is up to 50 digits 0.0
11448 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger subtraction 0.0
11664 Fetching from uHunt 2.2k, Big Integer, Easier simple simulation involving BigInteger 0.0
11821 Fetching from uHunt 2.2k, Big Integer, Easier Java BigDecimal class 0.0
11830 Fetching from uHunt 2.2k, Big Integer, Easier use BigInteger string representation 0.0
11879 Fetching from uHunt 2.2k, Big Integer, Easier BigInteger: mod; divide; subtract; equals 0.0
12143 Fetching from uHunt 2.2k, Big Integer, Easier LA 4209 - Dhaka08; formula simplification---the hard part; use BigInteger---the easy part 0.0
12459 Fetching from uHunt 2.2k, Big Integer, Easier draw the ancestor tree to see the pattern 0.0
12930 Fetching from uHunt 2.2k, Big Integer, Easier Java BigDecimal class; compareTo 0.0
buka buka 2.2k, Big Integer, Easier a trivial problem if we use Python or Java BigInteger 152 1.8
disastrousdoubling disastrousdoubling 2.2k, Big Integer, Easier simulation; wrong answer if not using Big Integer 324 3.7
generalizedrecursivefunctions generalizedrecursivefunctions 2.2k, Big Integer, Easier direct implementation of the given generalized recursive functions; but using Big Integer 141 3.9
lc0043 to replace with LeetCode link soon... 2.2k, Big Integer, Easier basic Big Integer multiplication; programming-skills 0 4.0
lc0415 to replace with LeetCode link soon... 2.2k, Big Integer, Easier basic Big Integer addition 0 2.0
lc0989 to replace with LeetCode link soon... 2.2k, Big Integer, Easier basic Big Integer addition 0 2.0
lidaskipting2 lidaskipting2 2.2k, Big Integer, Easier the most: n, the least: n//3 (plus 1 if it has remainder); use Big Integer 281 2.5
popkorn popkorn 2.2k, Big Integer, Easier simple formula; use Big Integer 761 3.1
primaryarithmetic primaryarithmetic 2.2k, Big Integer, Easier not a Big Integer problem but a simulation of basic addition 399 2.7
simpleaddition simpleaddition 2.2k, Big Integer, Easier that A+B on BigInteger question 1913 1.9
simplearithmetic simplearithmetic 2.2k, Big Integer, Easier trivial problem with Python (Big) Decimal 1113 4.5
threepowers threepowers 2.2k, Big Integer, Easier Big Integer is for 3^n; binary rep of set; also available at UVa 10669 - Three powers 700 2.6
wizardofodds wizardofodds 2.2k, Big Integer, Easier if K is bigger than 350, the answer is clear; else just check if 2^K ≥ N 488 2.6
lc2259 to replace with LeetCode link soon... 2.2l, Big Integer, Harder we can use Big Integer technique to solve this 0 2.0
00127 Fetching from uHunt 2.2m, Stack shuffling stack 0.0
00514 Fetching from uHunt 2.2m, Stack use stack to simulate the process 0.0
00732 Fetching from uHunt 2.2m, Stack use stack to simulate the process 0.0
01062 Fetching from uHunt 2.2m, Stack LA 3752 - WorldFinals Tokyo07; simulation with stack; maximum answer is 26 stacks; O(n) solution exists 0.0
10858 Fetching from uHunt 2.2m, Stack use stack 0.0
13055 Fetching from uHunt 2.2m, Stack nice problem about stack 0.0
bracketmatching bracketmatching 2.2m, Stack bracket matching; stack 1172 1.7
dream dream 2.2m, Stack stack simulation; reading comprehension problem, need other fast DS for mapping strings to indices 219 6.4
evenup evenup 2.2m, Stack use stack to solve this problem 1273 2.7
lc0071 to replace with LeetCode link soon... 2.2m, Stack complex stack simulation; top-interview-150 0 4.0
lc0345 to replace with LeetCode link soon... 2.2m, Stack we can use stack for this; leetcode-75 0 2.0
lc0394 to replace with LeetCode link soon... 2.2m, Stack more complex stack simulation; leetcode-75; top-100-liked 0 4.0
lc0682 to replace with LeetCode link soon... 2.2m, Stack stack simulation; programming-skills 0 2.0
lc0735 to replace with LeetCode link soon... 2.2m, Stack stack simulation; leetcode-75 0 4.0
lc0844 to replace with LeetCode link soon... 2.2m, Stack stack simulation 0 2.0
lc0917 to replace with LeetCode link soon... 2.2m, Stack stack simulation 0 2.0
lc1598 to replace with LeetCode link soon... 2.2m, Stack stack simulation; output last stack size 0 2.0
leidangur leidangur 2.2m, Stack stack simulation 333 2.1
pairingsocks pairingsocks 2.2m, Stack simulation using two stacks; just do as asked 556 3.0
restaurant restaurant 2.2m, Stack simulation with stack-based concept; drop plates at stack 2 (LIFO); use move 2-$gt;1 to reverse order; take from stack 1... 364 4.5
reversebinary reversebinary 2.2m, Stack decimal to binary; reverse it; binary to decimal 7144 1.5
symmetricorder symmetricorder 2.2m, Stack use stack to help reverse even-indexed names 3584 1.5
thegrandadventure thegrandadventure 2.2m, Stack stack simulation 348 2.0
throwns throwns 2.2m, Stack use stack of egg positions to help with the undo operation; be careful of corner cases involving modulo operation 1091 2.6
00551 Fetching from uHunt 2.2n, Stack-based Problems bracket matching; use stack 0.0
00673 Fetching from uHunt 2.2n, Stack-based Problems similar to UVa 551; classic 0.0
00727 Fetching from uHunt 2.2n, Stack-based Problems Infix to Postfix conversion problem 0.0
11111 Fetching from uHunt 2.2n, Stack-based Problems bracket matching with twists 0.0
bracketsequence bracketsequence 2.2n, Stack-based Problems bracket matching variant; stack; push a pair of (+ result, * result) for each '('; pop topmost pair for each ')'; operat... 100 5.5
bungeebuilder bungeebuilder 2.2n, Stack-based Problems clever usage of stack; linear pass; bracket (mountain) matching variant 83 3.3
circuitmath circuitmath 2.2n, Stack-based Problems postfix calculator problem 918 2.4
delimitersoup delimitersoup 2.2n, Stack-based Problems bracket matching; stack 382 1.9
lc0020 to replace with LeetCode link soon... 2.2n, Stack-based Problems bracket matching; stack; top-100-liked; top-interview-150 0 2.0
lc0032 to replace with LeetCode link soon... 2.2n, Stack-based Problems advanced bracket matching variant; top-100-liked 0 6.0
lc0084 to replace with LeetCode link soon... 2.2n, Stack-based Problems difficult O(n) solution with monotonic increasing stack; top-100-liked 0 6.0
lc0150 to replace with LeetCode link soon... 2.2n, Stack-based Problems classic postfix calculator; top-interview-150 0 4.0
lc0155 to replace with LeetCode link soon... 2.2n, Stack-based Problems monotonic non-increasing stack; top-100-liked; top-interview-150 0 4.0
lc0224 to replace with LeetCode link soon... 2.2n, Stack-based Problems infix-to-postfix and postfix calculator; top-interview-150 0 6.0
lc0739 to replace with LeetCode link soon... 2.2n, Stack-based Problems process right-to-left; monotonic non-increasing stack (temp, day); leetcode-75; top-100-liked 0 4.0
lc0901 to replace with LeetCode link soon... 2.2n, Stack-based Problems process left-to-right (each day); monotonic non-increasing stack (price, days_increasing); leetcode-75 0 4.0
lc0946 to replace with LeetCode link soon... 2.2n, Stack-based Problems need understanding of stack LIFO behavior 0 4.0
lc1021 to replace with LeetCode link soon... 2.2n, Stack-based Problems keep counter of open bracket; skip when counter is zero (the outermost layer) 0 2.0
lc1047 to replace with LeetCode link soon... 2.2n, Stack-based Problems bracket matching variant 0 2.0
lc1381 to replace with LeetCode link soon... 2.2n, Stack-based Problems need to edit the underlying array (bottom k) of the stack 0 4.0
lc2390 to replace with LeetCode link soon... 2.2n, Stack-based Problems bracket matching variant; leetcode-75 0 4.0
lc3174 to replace with LeetCode link soon... 2.2n, Stack-based Problems bracket matching variant; match a digit with closest non-digit; LIFO; stack 0 2.0
00246 Fetching from uHunt 2.2o, List/Queue/Deque card simulation with queue and deque 0.0
00540 Fetching from uHunt 2.2o, List/Queue/Deque modified queue 0.0
10172 Fetching from uHunt 2.2o, List/Queue/Deque use both queue and stack 0.0
10901 Fetching from uHunt 2.2o, List/Queue/Deque simulation with queue; also available at Kattis - ferryloading3 0.0
10935 Fetching from uHunt 2.2o, List/Queue/Deque simulation with queue 0.0
11034 Fetching from uHunt 2.2o, List/Queue/Deque simulation with queue; also available at Kattis - ferryloading4 0.0
11797 Fetching from uHunt 2.2o, List/Queue/Deque simulation with 5 queues 0.0
11988 Fetching from uHunt 2.2o, List/Queue/Deque rare linked list problem 0.0
12100 Fetching from uHunt 2.2o, List/Queue/Deque simulation with queue 0.0
12108 Fetching from uHunt 2.2o, List/Queue/Deque simulation with N queues 0.0
12207 Fetching from uHunt 2.2o, List/Queue/Deque use both queue and deque 0.0
backspace backspace 2.2o, List/Queue/Deque we can use deque (or vector) to help solve this problem 2517 3.0
bendilfaerslur bendilfaerslur 2.2o, List/Queue/Deque reverse list; splice list; append list; output formatting 268 2.5
ferryloading3 ferryloading3 2.2o, List/Queue/Deque simulation with queue; also available at UVa 10901 - Ferry Loading III 368 3.6
ferryloading4 ferryloading4 2.2o, List/Queue/Deque simulation with queue; also available at UVa 11034 - Ferry Loading IV 703 3.6
foosball foosball 2.2o, List/Queue/Deque queue simulation; tedious 186 3.7
integerlists integerlists 2.2o, List/Queue/Deque use deque for fast deletion from front (normal) & back (reversed list); use stack to reverse the final list if it is... 882 4.8
joinstrings joinstrings 2.2o, List/Queue/Deque all '+' operations must be O(1) 959 4.1
lc0232 to replace with LeetCode link soon... 2.2o, List/Queue/Deque the interesting implementation of queue with two stacks: in-stack and out-stack 0 2.0
lc0362 to replace with LeetCode link soon... 2.2o, List/Queue/Deque PREMIUM - hint hidden 0 4.0
lc0622 to replace with LeetCode link soon... 2.2o, List/Queue/Deque the interesting implementation of circular queue 0 4.0
lc0649 to replace with LeetCode link soon... 2.2o, List/Queue/Deque queue simulation; reading comprehension; leetcode-75 0 4.0
lc0933 to replace with LeetCode link soon... 2.2o, List/Queue/Deque queue simulation; leetcode-75 0 2.0
lyklagangriti lyklagangriti 2.2o, List/Queue/Deque use list and its iterator; very similar to Kattis - sim 114 2.7
midi midi 2.2o, List/Queue/Deque use deque/stack of stacks; other ways exist 452 2.1
server server 2.2o, List/Queue/Deque one first come first serve pass; we can use queue although overkill 3331 1.9
sim sim 2.2o, List/Queue/Deque use list and its iterator 99 2.0
teque teque 2.2o, List/Queue/Deque all operations must be O(1) 766 3.3
trendingtopic trendingtopic 2.2o, List/Queue/Deque use queue of length 7 to maintain words in the past 7 days, unordered_map to count frequencies, sort to format the outpu... 181 5.8
lc0011 to replace with LeetCode link soon... 2.2p, 1D Array, Two Pointers two pointers, l=0, r=n-1; we can always move the shorter pointer inside; leetcode-75; top-100-liked; top-interview-150 0 4.0
lc0026 to replace with LeetCode link soon... 2.2p, 1D Array, Two Pointers we can use two pointers to maintain a growing window of unique elements; top-interview-150 0 2.0
lc0080 to replace with LeetCode link soon... 2.2p, 1D Array, Two Pointers just a small update compared to LC 0026; top-interview-150 0 4.0
lc0167 to replace with LeetCode link soon... 2.2p, 1D Array, Two Pointers two pointers: leftmost and rightmost; top-interview-150 0 4.0
lc0283 to replace with LeetCode link soon... 2.2p, 1D Array, Two Pointers two pointers: leftmost zero and cur; programming-skills; leetcode-75; top-100-liked 0 2.0
lc0392 to replace with LeetCode link soon... 2.2p, 1D Array, Two Pointers variant of merge of Merge sort; leetcode-75; top-interview-150 0 2.0
lc1023 to replace with LeetCode link soon... 2.2p, 1D Array, Two Pointers for each query; do two pointers between query and pattern strings 0 4.0
lc1437 to replace with LeetCode link soon... 2.2p, 1D Array, Two Pointers two pointers: prev_1 and cur 0 2.0
lc1768 to replace with LeetCode link soon... 2.2p, 1D Array, Two Pointers variant of merge of Merge sort; programming-skills; leetcode-75 0 2.0
lc2090 to replace with LeetCode link soon... 2.2p, 1D Array, Two Pointers 2 pointers: l and r (2*k indices away); slide both pointers together 0 4.0
lc2562 to replace with LeetCode link soon... 2.2p, 1D Array, Two Pointers two pointers: left and right; move inwards 0 2.0
00261 Fetching from uHunt 2.2q, Sliding Window sliding window variant 0.0
01121 Fetching from uHunt 2.2q, Sliding Window LA 2678 - SouthEasternEurope06; sliding window variant 0.0
11536 Fetching from uHunt 2.2q, Sliding Window sliding window variant 0.0
inquiryi inquiryi 2.2q, Sliding Window sliding window; maintain left and right pointers 25 3.2
lc0003 to replace with LeetCode link soon... 2.2q, Sliding Window increase char freq when extending; reduce window size if duplicate is seen; top-100-liked; top-interview-150 0 4.0
lc0076 to replace with LeetCode link soon... 2.2q, Sliding Window maintain character frequencies as we slide the window; top-100-liked; top-interview-150 0 6.0
lc0209 to replace with LeetCode link soon... 2.2q, Sliding Window add each Integer into window; reduce window if its sum exceeds target; keep the smallest window size; top-interview-150 0 4.0
lc0239 to replace with LeetCode link soon... 2.2q, Sliding Window similar to Kattis - sound; sliding window; deque; top-100-liked 0 6.0
lc0346 to replace with LeetCode link soon... 2.2q, Sliding Window PREMIUM - hint hidden 0 2.0
lc0438 to replace with LeetCode link soon... 2.2q, Sliding Window maintain character frequencies as we slide the window; top-100-liked 0 4.0
lc0643 to replace with LeetCode link soon... 2.2q, Sliding Window slide the window of size k; keep the max; divide by k; leetcode-75 0 2.0
lc1004 to replace with LeetCode link soon... 2.2q, Sliding Window decide window adjustment if 1 vs 0; keep the largest window size; leetcode-75 0 4.0
lc1343 to replace with LeetCode link soon... 2.2q, Sliding Window slide the window of size k; check window's average against threshold 0 4.0
lc1456 to replace with LeetCode link soon... 2.2q, Sliding Window slide the window of size k; adjust number of vowel within the window as we slide; keep the max; leetcode-75 0 4.0
lc1493 to replace with LeetCode link soon... 2.2q, Sliding Window similar to LC 1004; leetcode-75 0 4.0
martiandna martiandna 2.2q, Sliding Window sliding window variant 2; maintain left pointer and histogram of frequencies; keep the smallest window size 297 2.4
slidecount slidecount 2.2q, Sliding Window sliding window variant 1; record the first and last iteration an index is touched; the difference is the answer 170 4.2
sound sound 2.2q, Sliding Window sliding window variant 4; max and min; similar to Kattis - treeshopping 104 5.3
subseqhard subseqhard 2.2q, Sliding Window interesting sliding window variant 1119 3.9
treeshopping treeshopping 2.2q, Sliding Window sliding window variant 4; max and min; similar to Kattis - sound 62 3.4
01203 Fetching from uHunt 2.3a, Priority Queue LA 3135 - Beijing04; use priority_queue 0.0
11995 Fetching from uHunt 2.3a, Priority Queue stack; queue; and priority_queue 0.0
11997 Fetching from uHunt 2.3a, Priority Queue sort the lists; merge two sorted lists using priority_queue to keep the K-th smallest sum every time 0.0
13190 Fetching from uHunt 2.3a, Priority Queue similar to UVa 01203; use PQ; use drug numbering id as tie-breaker 0.0
alehouse alehouse 2.3a, Priority Queue discretize the events; PQ simulation 223 4.6
clinic clinic 2.3a, Priority Queue interesting PQ simulation; reverse thinking; project to time 0 165 3.0
guessthedatastructure guessthedatastructure 2.3a, Priority Queue stack, queue, and priority_queue; also available at UVa 11995 - I Can Guess ... 2148 2.5
heap heap 2.3a, Priority Queue basic Binary (Max) Heap implementation task 11 5.8
janeeyre janeeyre 2.3a, Priority Queue simulate Anna's reading behavior with PQ; the input parsing is tedious 79 4.8
jugglingpatterns jugglingpatterns 2.3a, Priority Queue PQ simulation; reading comprehension 48 6.3
knigsoftheforest knigsoftheforest 2.3a, Priority Queue PQ simulation after sorting the entries by year 184 3.6
lc0023 to replace with LeetCode link soon... 2.3a, Priority Queue extract next min (+ list i); enqueue next min from list i; construct output; top-100-liked; top-interview-150 0 6.0
lc0215 to replace with LeetCode link soon... 2.3a, Priority Queue use Python heapq nlargest library; leetcode-75; top-100-liked; top-interview-150 0 4.0
lc0264 to replace with LeetCode link soon... 2.3a, Priority Queue min PQ simulation; if x is the current smallest; add 2x, 3x, and 5x into min PQ, if they are not seen before 0 4.0
lc0373 to replace with LeetCode link soon... 2.3a, Priority Queue repeat k times: enqueue next from nums1 and next from nums2; avoid duplicate with set 0 4.0
lc1046 to replace with LeetCode link soon... 2.3a, Priority Queue simple max PQ simulation 0 2.0
lc1845 to replace with LeetCode link soon... 2.3a, Priority Queue min PQ simulation; initially put 1 to n 0 4.0
lc1962 to replace with LeetCode link soon... 2.3a, Priority Queue max PQ simulation 0 4.0
lc2335 to replace with LeetCode link soon... 2.3a, Priority Queue max PQ simulation 0 2.0
lc2336 to replace with LeetCode link soon... 2.3a, Priority Queue min PQ simulation; up to 1000 calls involving [1..1000]; avoid duplicates; leetcode-75 0 4.0
lc2462 to replace with LeetCode link soon... 2.3a, Priority Queue min PQ simulation; two pointers: i=0 and j=n-1; move inwards; leetcode-75 0 4.0
lc2530 to replace with LeetCode link soon... 2.3a, Priority Queue max PQ simulation 0 4.0
lc2558 to replace with LeetCode link soon... 2.3a, Priority Queue max PQ simulation 0 2.0
lc3066 to replace with LeetCode link soon... 2.3a, Priority Queue min PQ simulation 0 4.0
numbertree numbertree 2.3a, Priority Queue not a direct priority queue problem, but the indexing strategy is similar to binary heap indexing 1760 2.1
pharmacy pharmacy 2.3a, Priority Queue simulation with PQ (time) and 2 normal queues (in-store vs remote) 118 3.4
rationalsequence2 rationalsequence2 2.3a, Priority Queue the L/R pattern can be easily derived and indexing strategy is similar to binary heap indexing 1388 1.5
rationalsequence3 rationalsequence3 2.3a, Priority Queue the reverse problem of rationalsequence2 587 1.8
stockprices stockprices 2.3a, Priority Queue PQ simulation; both max and min PQ 109 3.7
00499 Fetching from uHunt 2.3b, DAT, ASCII ASCII keys 0.0
00895 Fetching from uHunt 2.3b, DAT, ASCII get the letter frequency of each word; compare with puzzle line 0.0
10008 Fetching from uHunt 2.3b, DAT, ASCII A-Z keys 0.0
10062 Fetching from uHunt 2.3b, DAT, ASCII ASCII character frequency count 0.0
10260 Fetching from uHunt 2.3b, DAT, ASCII DAT for soundex A-Z code mapping; also available at Kattis - soundex 0.0
10293 Fetching from uHunt 2.3b, DAT, ASCII A-Z keys 0.0
10625 Fetching from uHunt 2.3b, DAT, ASCII ASCII character; frequency addition n times 0.0
11340 Fetching from uHunt 2.3b, DAT, ASCII ASCII keys 0.0
11577 Fetching from uHunt 2.3b, DAT, ASCII A-Z keys 0.0
12626 Fetching from uHunt 2.3b, DAT, ASCII A-Z keys 0.0
alphabetspam alphabetspam 2.3b, DAT, ASCII count the frequencies of lowercase, uppercase, and whitespace characters 3902 1.4
cyclicalperiods cyclicalperiods 2.3b, DAT, ASCII DAT of last occurrence of 26 chars [`a`..`z`], keep the running max 112 3.0
keyboardd keyboardd 2.3b, DAT, ASCII frequency counting of A-Zs and spaces 92 2.0
lc0383 to replace with LeetCode link soon... 2.3b, DAT, ASCII two DATs ('a'..'z'); check for all 'a'..'z'; top-interview-150 0 2.0
lc0387 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); counter 0 2.0
lc0389 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); programming-skills 0 2.0
lc0748 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); counter 0 2.0
lc0771 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('A'..'Z' and 'a'..'z'); simple check 0 2.0
lc1160 to replace with LeetCode link soon... 2.3b, DAT, ASCII use two DATs ('a'..'z'); compare 0 2.0
lc1189 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); per `balloon', we need 1 'ban' and 2 'lo' 0 2.0
lc1624 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); simple check 0 2.0
lc1629 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); simple check 0 2.0
lc1832 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); check if all freq are non-zero 0 2.0
lc1897 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); counter 0 2.0
lc1935 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); Boolean (broken or not) 0 2.0
lc1941 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); counter 0 2.0
lc2068 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); counter; simple check 0 2.0
lc2186 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); counter; add absolute differences 0 4.0
lc2278 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); simple 0 2.0
lc2287 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); counter; check 0 2.0
lc2351 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); find the first with freq 2 0 2.0
lc2399 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); remember first occurrence 0 2.0
lc2405 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); has this char been seen? 0 4.0
lc3039 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); counter; find max f; check with new counter 0 4.0
lc3121 to replace with LeetCode link soon... 2.3b, DAT, ASCII two DATs ('a'..'z'); last_lower and first_upper; check 0 4.0
lc3146 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ('a'..'z'); map character to index 0 2.0
lc3442 to replace with LeetCode link soon... 2.3b, DAT, ASCII DAT ['a'..'z']; split even/odd; sort 0 2.0
quickbrownfox quickbrownfox 2.3b, DAT, ASCII pangram; frequency counting of 26 alphabets 4433 1.6
soundex soundex 2.3b, DAT, ASCII DAT for soundex A-Z code mapping; also available at UVa 10260 - Soundex 106 2.9
00755 Fetching from uHunt 2.3c, DAT, Others Direct Addressing Table; convert the letters except Q and Z to 2-9; keep 0-9 as 0-9; sort the integers; find duplicates ... 0.0
01368 Fetching from uHunt 2.3c, DAT, Others for each column j, find the highest frequency character among all j-th column of all m DNA strings 0.0
11203 Fetching from uHunt 2.3c, DAT, Others count frequency of x/y/z 0.0
12650 Fetching from uHunt 2.3c, DAT, Others use 1D Boolean array for each person 0.0
bladra bladra 2.3c, DAT, Others DAT of frequencies of size k; find min 324 2.0
bookingaroom bookingaroom 2.3c, DAT, Others only 100 rooms; use 1D Boolean array 2849 1.7
busnumbers busnumbers 2.3c, DAT, Others only 1000 bus numbers; use 1D Boolean array 2776 2.4
dontbefake dontbefake 2.3c, DAT, Others it is sufficient to use DAT of size 86400 to get the required answers efficiently 100 2.9
freefood freefood 2.3c, DAT, Others only 365 days in a year 1965 1.5
hardware hardware 2.3c, DAT, Others parsing is tedious; count the frequency of digits 244 2.0
heimavinna heimavinna 2.3c, DAT, Others DAT of 1000 problems 431 1.4
lc0379 to replace with LeetCode link soon... 2.3c, DAT, Others PREMIUM - hint hidden 0 4.0
lc0645 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..10000]; find key with freq 2 (repeated) and 0 (missing) 0 2.0
lc0788 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [0..9]; map digit to its rotation or NIL; 0 4.0
lc0869 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [0..9]; compare digit frequency of n with all powers of 2 up to 2^30 0 4.0
lc0961 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [0..10000]; find key with freq n 0 2.0
lc1357 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..200] for price of each product; remember customer count; simulate 0 4.0
lc1748 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..100]; counter; sum i if frequency of i is 1 0 2.0
lc1854 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1950..2050]; counter; find earliest year with max freq 0 2.0
lc1893 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..50] Booleans; 0 2.0
lc2190 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..1000]; do as asked 0 2.0
lc2206 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..500]; counter; check even frequencies 0 2.0
lc2283 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [0..9]; counter; do as asked 0 2.0
lc2341 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [0..100]; trivial after frequencies of each integers are known 0 2.0
lc2357 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [0..100]; counter; count number of distinct positive numbers 0 2.0
lc2409 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..365]; mark Alice and Bob days in Rome; count freq 2 0 2.0
lc2491 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..1000]; sort the skills; use DAT to help 0 4.0
lc2570 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..1000]; sum the values 0 2.0
lc2682 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..50]; counter; identify freq 0s 0 2.0
lc2729 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [0..9]; counter; do as asked 0 2.0
lc2784 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [0..200]; check as asked 0 2.0
lc2965 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..2500]; counter; check as required 0 2.0
lc3005 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..100]; counter; do as asked 0 2.0
lc3046 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..100]; frequency difference at most two 0 2.0
lc3158 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [1..50]; xor those with freq = 2 0 2.0
lc3238 to replace with LeetCode link soon... 2.3c, DAT, Others 2D DAT n x [0..10]; counter 0 2.0
lc3289 to replace with LeetCode link soon... 2.3c, DAT, Others DAT [0..100]; find two keys with freq = 2 0 2.0
princesspeach princesspeach 2.3c, DAT, Others DAT; linear pass 839 2.1
relocation relocation 2.3c, DAT, Others just use DAT 1112 1.5
simone simone 2.3c, DAT, Others DAT to count frequencies of [1..K] 106 1.6
superyatzy superyatzy 2.3c, DAT, Others use frequency counter DAT for side [1..6]; see if the frequency of any side + M is sufficient 282 1.6
10887 Fetching from uHunt 2.3d, Hash Table (set), E Use O(M*N*log(MN)*10) algorithm; concatenate all pairs of strings; put them in a set; report set size 0.0
11849 Fetching from uHunt 2.3d, Hash Table (set), E unordered_set is faster than set here; or use modified merge as the input is sorted; also available at Kattis - cd 0.0
12049 Fetching from uHunt 2.3d, Hash Table (set), E unordered_multiset manipulation 0.0
13148 Fetching from uHunt 2.3d, Hash Table (set), E we can store all precomputed answers - which are given - into unordered_set 0.0
bard bard 2.3d, Hash Table (set), E use one unordered_set per villager; simulate the singing process 637 2.6
boatparts boatparts 2.3d, Hash Table (set), E use unordered_set 1398 1.6
cd cd 2.3d, Hash Table (set), E unordered_set is faster than set here; or use modified merge as the input is sorted; also available at UVa 11849 - CD 3176 5.3
deduplicatingfiles deduplicatingfiles 2.3d, Hash Table (set), E use vector to store the strings; unordered_set to store unique strings; and complete search to compare the n^2 hash code... 583 4.4
engineeringenglish engineeringenglish 2.3d, Hash Table (set), E use unordered_set to remember duplicated words; transform to lowercase 1627 2.2
esej esej 2.3d, Hash Table (set), E use unordered_set to prevent duplicate 509 3.3
everywhere everywhere 2.3d, Hash Table (set), E use unordered_set 7015 1.4
icpcawards icpcawards 2.3d, Hash Table (set), E use unordered_set; print first 12 distinct Universities (and their first teams) 2167 1.4
icpcrecordmatching icpcrecordmatching 2.3d, Hash Table (set), E string processing; set of emails/names; sort the output 111 4.2
iwannabe iwannabe 2.3d, Hash Table (set), E sort Pokenoms based on each stat; pick top K ids and put in an unordered_set; report final size of unordered_set 739 2.5
jage jage 2.3d, Hash Table (set), E set simulation; sort at the end 408 2.2
keywords keywords 2.3d, Hash Table (set), E pre-process the strings; put inside unordered_set; report final size 349 2.3
knotknowledge knotknowledge 2.3d, Hash Table (set), E simple set difference problem 890 1.5
lc0349 to replace with LeetCode link soon... 2.3d, Hash Table (set), E set (no duplicate) intersection 0 2.0
lc0500 to replace with LeetCode link soon... 2.3d, Hash Table (set), E simulate; use 3 sets of chars (one per row) to speed-up 0 2.0
lc0575 to replace with LeetCode link soon... 2.3d, Hash Table (set), E min of n/2 vs number of different candy types 0 2.0
lc0929 to replace with LeetCode link soon... 2.3d, Hash Table (set), E string processing; put to set; set size 0 2.0
lc2215 to replace with LeetCode link soon... 2.3d, Hash Table (set), E use set for fast tests; leetcode-75 0 2.0
lc2441 to replace with LeetCode link soon... 2.3d, Hash Table (set), E turn nums into a set; then do a complete search test 0 2.0
lc2442 to replace with LeetCode link soon... 2.3d, Hash Table (set), E simulate; add to set; report set size 0 4.0
lc3295 to replace with LeetCode link soon... 2.3d, Hash Table (set), E convert bannedWords list to set for faster lookup; then just check all string in message 0 4.0
nodup nodup 2.3d, Hash Table (set), E use unordered_set; string 3564 1.3
oddmanout oddmanout 2.3d, Hash Table (set), E use unordered_set to find and eliminate pairs 4450 1.5
pizzahawaii pizzahawaii 2.3d, Hash Table (set), E use Python to help with (unordered) set intersection and difference operations 335 2.6
proofs proofs 2.3d, Hash Table (set), E parsing; use unordered_set to store past conclusions; a few corner cases 48 2.4
pusluspil pusluspil 2.3d, Hash Table (set), E set union problem 164 2.0
securedoors securedoors 2.3d, Hash Table (set), E use unordered_set to keep track of the people 2108 1.8
shiritori shiritori 2.3d, Hash Table (set), E linear pass; use unordered_set to keep track of words that have been called 295 2.9
shoppinglist shoppinglist 2.3d, Hash Table (set), E simple set intersection problem 16 4.4
shoppinglisteasy shoppinglisteasy 2.3d, Hash Table (set), E see Kattis - shoppinglist 23 3.4
thoringtest thoringtest 2.3d, Hash Table (set), E lowercase all inputs; see if all words are known by Thore; use set 38 2.8
tripodometer tripodometer 2.3d, Hash Table (set), E let s = sum(d); subtract s by each d_i; keep the answers in a set; sort 185 2.1
upprodun upprodun 2.3d, Hash Table (set), E not really a Hash Table problem but uses Hash Table concept; the number of teams in each room is the 'load factor' of th... 197 1.9
variabelnamn variabelnamn 2.3d, Hash Table (set), E hash table (set) and DAT simulation 411 3.0
whatdoesthefoxsay whatdoesthefoxsay 2.3d, Hash Table (set), E use unordered_set to record excluded sounds 2578 2.1
greetingcard greetingcard 2.3e, Hash Table (set), H use unordered_set; only 12 neighbors 607 4.9
lc0128 to replace with LeetCode link soon... 2.3e, Hash Table (set), H create set of nums; keep checking if val+1 also exists in num; avoid recomputation; top-100-liked; top-interview-150 0 4.0
00484 Fetching from uHunt 2.3f, Hash Table (map), E maintain frequency with map 0.0
00860 Fetching from uHunt 2.3f, Hash Table (map), E frequency counting 0.0
00902 Fetching from uHunt 2.3f, Hash Table (map), E read char by char; count word freq 0.0
10282 Fetching from uHunt 2.3f, Hash Table (map), E a pure dictionary problem; use unordered_map; also available at Kattis - babelfish 0.0
10295 Fetching from uHunt 2.3f, Hash Table (map), E use unordered_map to deal with Hay Points dictionary; also available at Kattis - haypoints 0.0
10374 Fetching from uHunt 2.3f, Hash Table (map), E use unordered_map for frequency counting 0.0
10686 Fetching from uHunt 2.3f, Hash Table (map), E use map to manage the data 0.0
11286 Fetching from uHunt 2.3f, Hash Table (map), E use unordered_map to count frequencies of the sorted permutations of 5 ids; also available at Kattis - conformity 0.0
11348 Fetching from uHunt 2.3f, Hash Table (map), E use map and set to check uniqueness 0.0
11629 Fetching from uHunt 2.3f, Hash Table (map), E use map 0.0
12592 Fetching from uHunt 2.3f, Hash Table (map), E use map; string to string 0.0
akureyri akureyri 2.3f, Hash Table (map), E simple frequency counter 295 1.4
babelfish babelfish 2.3f, Hash Table (map), E a pure dictionary problem; use unordered_map; also available at UVa 10282 - Babelfish 2835 2.3
candystore candystore 2.3f, Hash Table (map), E we can use hash table; but easier solution exists 447 1.5
competitivearcadebasketball competitivearcadebasketball 2.3f, Hash Table (map), E use unordered_map 209 2.8
conformity conformity 2.3f, Hash Table (map), E use unordered_map to count frequencies of the sorted permutations of 5 ids; also available at UVa 11286 - Conformity 1100 1.9
costumecontest costumecontest 2.3f, Hash Table (map), E use unordered_map to map frequency of each category; get the minimum one; print output lexicographically 532 2.0
drinkmenu drinkmenu 2.3f, Hash Table (map), E hashmap simulation 242 1.5
eiginnofn eiginnofn 2.3f, Hash Table (map), E use two hashtables (one set and one dictionary) 321 2.0
election2 election2 2.3f, Hash Table (map), E frequency counting; be careful of tie breaker 166 2.4
gandalfsspell gandalfsspell 2.3f, Hash Table (map), E map string to char and char to string 86 2.5
grandpabernie grandpabernie 2.3f, Hash Table (map), E use unordered_map plus (sorted) vector 1065 3.2
haypoints haypoints 2.3f, Hash Table (map), E use unordered_map to deal with Hay Points dictionary; also available at UVa 10295 - Hay Points 1055 2.0
lc0205 to replace with LeetCode link soon... 2.3f, Hash Table (map), E mapper and reverse mapper from char to another char; top-interview-150 0 2.0
lc0290 to replace with LeetCode link soon... 2.3f, Hash Table (map), E mapper and reverse mapper from char to string; top-interview-150 0 2.0
lc0359 to replace with LeetCode link soon... 2.3f, Hash Table (map), E PREMIUM - hint hidden 0 2.0
lc0535 to replace with LeetCode link soon... 2.3f, Hash Table (map), E simple mapper from longUrl to shortUrl and back 0 4.0
lc0594 to replace with LeetCode link soon... 2.3f, Hash Table (map), E use Counter; then it is simple 0 2.0
lc0884 to replace with LeetCode link soon... 2.3f, Hash Table (map), E use Counter for all tokens in s1 and s2; do as asked 0 2.0
lc1207 to replace with LeetCode link soon... 2.3f, Hash Table (map), E use Counter and set (to test for uniqueness); leetcode-75 0 2.0
lc1287 to replace with LeetCode link soon... 2.3f, Hash Table (map), E use Counter and test 0 2.0
lc1346 to replace with LeetCode link soon... 2.3f, Hash Table (map), E use Counter and check; special case with 0 as its double is also 0 (its frequency must be at least 2) 0 2.0
lc1394 to replace with LeetCode link soon... 2.3f, Hash Table (map), E use Counter; find key == value 0 2.0
lc1679 to replace with LeetCode link soon... 2.3f, Hash Table (map), E frequency Counter; pairings; leetcode-75 0 4.0
marko marko 2.3f, Hash Table (map), E frequency counting with unordered_map 495 1.9
metaprogramming metaprogramming 2.3f, Hash Table (map), E use unordered_map; somewhat similar with Kattis - addingwords 820 2.4
nicknames nicknames 2.3f, Hash Table (map), E use unordered_map of frequency of prefixes 364 3.3
pakethanterare pakethanterare 2.3f, Hash Table (map), E map package name to version number 454 2.0
pencilcrayons pencilcrayons 2.3f, Hash Table (map), E for each box, count number of element > 1 (offset -1) 384 1.5
planets2 planets2 2.3f, Hash Table (map), E map species name to planet name; frequency counting 106 3.5
recount recount 2.3f, Hash Table (map), E use map; frequency counting 1163 2.0
rollcall rollcall 2.3f, Hash Table (map), E use unordered_map to count frequency; sort 530 2.4
streetsahead streetsahead 2.3f, Hash Table (map), E map street name to linear indices; find the absolute differences of the indices per query 438 2.1
toktik toktik 2.3f, Hash Table (map), E standard frequency counter problem with hash table 451 1.5
translation translation 2.3f, Hash Table (map), E simple mapper 351 1.4
variablearithmetic variablearithmetic 2.3f, Hash Table (map), E use unordered_map as mapper 394 2.6
lc0137 to replace with LeetCode link soon... 2.3g, Hash Table (Counter) not intended solution: use Counter 0 4.0
lc0170 to replace with LeetCode link soon... 2.3g, Hash Table (Counter) PREMIUM - hint hidden 0 2.0
lc0347 to replace with LeetCode link soon... 2.3g, Hash Table (Counter) use Counter to count frequency; sort by frequencies; top k; top-100-liked 0 4.0
lc0448 to replace with LeetCode link soon... 2.3g, Hash Table (Counter) Counter; find freq 0s 0 2.0
lc0540 to replace with LeetCode link soon... 2.3g, Hash Table (Counter) non-intended Counter solution; O(n) time and O(n) space 0 4.0
lc0697 to replace with LeetCode link soon... 2.3g, Hash Table (Counter) Counter; max; find candidates; compare rightmost-leftmost indices of each candidate 0 2.0
00417 Fetching from uHunt 2.3h, Hash Table (map), H generate all words; add to map for auto sorting 0.0
10132 Fetching from uHunt 2.3h, Hash Table (map), H use map; brute force 0.0
10145 Fetching from uHunt 2.3h, Hash Table (map), H use map and set 0.0
11572 Fetching from uHunt 2.3h, Hash Table (map), H use unordered_map to record the occurrence index of a certain snowflake size; use this to determine the answer in linear... 0.0
11860 Fetching from uHunt 2.3h, Hash Table (map), H use set and map; linear scan 0.0
11917 Fetching from uHunt 2.3h, Hash Table (map), H use map 0.0
addingwords addingwords 2.3h, Hash Table (map), H use unordered_map 1880 3.9
awkwardparty awkwardparty 2.3h, Hash Table (map), H use unordered_map to running max and running min; report the largest difference 611 3.0
basicinterpreter basicinterpreter 2.3h, Hash Table (map), H the harder version of Kattis - variablearithmetic; tedious; be careful; print string inside double quotes verbatim 152 6.7
bokforing bokforing 2.3h, Hash Table (map), H use unordered_map to map index to value; for each 'RESTART', clear the hash table in 'faster than O(N)' (amortized) and ... 493 3.8
conversationlog conversationlog 2.3h, Hash Table (map), H use combo DS: unordered_map, set, plus (sorted) vector 507 2.8
iforaneye iforaneye 2.3h, Hash Table (map), H use unordered_map to map the various rules mentioned in the problem description; tedious 143 5.0
kaploeb kaploeb 2.3h, Hash Table (map), H hash the total time and lap count of each start number; sort at the end 899 2.3
lc0139 to replace with LeetCode link soon... 2.3h, Hash Table (map), H s: (i); t: try each word in dictionary; top-100-liked; top-interview-150 0 4.0
lc0146 to replace with LeetCode link soon... 2.3h, Hash Table (map), H combination of two hashtables (mapper; last_used) and queue of events; top-100-liked; top-interview-150 0 4.0
lc0677 to replace with LeetCode link soon... 2.3h, Hash Table (map), H hash all the prefixes of key; becareful with the overwrite requirement 0 4.0
lc0819 to replace with LeetCode link soon... 2.3h, Hash Table (map), H clean up the paragraph; frequency counter of strings; report the most common 0 2.0
lc0981 to replace with LeetCode link soon... 2.3h, Hash Table (map), H hash string to sorted list of (timestamps, values); binary search 0 4.0
lc1002 to replace with LeetCode link soon... 2.3h, Hash Table (map), H Python Counter intersection (to handle duplicates) 0 2.0
magicalcows magicalcows 2.3h, Hash Table (map), H use unordered_map of farm size to frequency; small simulation; but since C is small, we can also use DAT 257 4.6
minorsetback minorsetback 2.3h, Hash Table (map), H use unordered_map of string to another unordered_map of int to string; need a bit of music theory to solve the problem; ... 147 3.6
parallelanalysis parallelanalysis 2.3h, Hash Table (map), H reading comprehension; use unordered_map to map memory address to last time it is written 80 4.8
recenice recenice 2.3h, Hash Table (map), H use unordered_map to prepare pronunciation of [1..999]; precalculate the answer afterwards using another unordered_map 225 3.1
snowflakes snowflakes 2.3h, Hash Table (map), H use unordered_map to record the occurrence index of a certain snowflake size; use this to determine the answer in linear... 404 4.4
00501 Fetching from uHunt 2.3i, Balanced BST (set) use multiset with efficient iterator manipulation 0.0
00978 Fetching from uHunt 2.3i, Balanced BST (set) simulation; use multiset 0.0
10815 Fetching from uHunt 2.3i, Balanced BST (set) use set and string 0.0
11062 Fetching from uHunt 2.3i, Balanced BST (set) similar to UVa 10815 with twists 0.0
11136 Fetching from uHunt 2.3i, Balanced BST (set) use multiset 0.0
13037 Fetching from uHunt 2.3i, Balanced BST (set) we can use set or a sorted array 0.0
bst bst 2.3i, Balanced BST (set) simulate special BST [1..N] insertions using set 449 7.3
caching caching 2.3i, Balanced BST (set) combo ds (unordered_map and set) 210 5.8
candydivision candydivision 2.3i, Balanced BST (set) complete search from 1 to sqrt(N); insert all divisors into set for automatic sorting and elimination of duplicates 702 3.4
compoundwords compoundwords 2.3i, Balanced BST (set) use set extensively; iterator 1807 1.7
coursescheduling coursescheduling 2.3i, Balanced BST (set) keep (ordered) set of courses and (unordered) map of course to students taking the course 40 3.1
lc0056 to replace with LeetCode link soon... 2.3i, Balanced BST (set) maintain set of intervals using bBST (set); do quick merging of intervals; top-100-liked; top-interview-150 0 4.0
lc0057 to replace with LeetCode link soon... 2.3i, Balanced BST (set) very similar to LC 0056; top-interview-150 0 4.0
ministryofmagic ministryofmagic 2.3i, Balanced BST (set) simulate directly, use of queue and set (PQ with update key/increase key; use STL set) 63 6.0
missinggnomes missinggnomes 2.3i, Balanced BST (set) use set to keep ordered list of missing gnomes 659 2.6
orphanbackups orphanbackups 2.3i, Balanced BST (set) use set for auto sorting 94 6.2
palindromicpassword palindromicpassword 2.3i, Balanced BST (set) there are not more than 900 3-digits number; generate all and store them in a (sorted) set; find ceil and floor of input... 431 3.3
raceday raceday 2.3i, Balanced BST (set) use combo of map; multiset (the most important part for the rankings); and unordered_map 184 3.8
raidteams raidteams 2.3i, Balanced BST (set) use more than one PQs that can support erase operation 75 3.5
00939 Fetching from uHunt 2.3j, Balanced BST (map) map child name to his/her gene and parents' names 0.0
10138 Fetching from uHunt 2.3j, Balanced BST (map) map plates to bills; entrance time; and position 0.0
10226 Fetching from uHunt 2.3j, Balanced BST (map) use map; sorted output; also available at Kattis - hardwoodspecies 0.0
10420 Fetching from uHunt 2.3j, Balanced BST (map) word frequency counting; use map 0.0
11239 Fetching from uHunt 2.3j, Balanced BST (map) use map and set to check previous strings; order needed; also available at Kattis - opensource 0.0
11308 Fetching from uHunt 2.3j, Balanced BST (map) use map and set 0.0
12504 Fetching from uHunt 2.3j, Balanced BST (map) use map; string to string 0.0
administrativeproblems administrativeproblems 2.3j, Balanced BST (map) use several maps as the output (of spy names) has to be sorted; be careful of corner cases 194 6.3
baconeggsandspam baconeggsandspam 2.3j, Balanced BST (map) use map; sort 1712 1.6
cakeymccakeface cakeymccakeface 2.3j, Balanced BST (map) map differences to frequencies; return the one with maximum frequency and if ties, the smallest difference 197 3.8
doctorkattis doctorkattis 2.3j, Balanced BST (map) Max Priority Queue with frequent (increaseKey) updates; use map 114 4.7
fantasydraft fantasydraft 2.3j, Balanced BST (map) use map to keep ordering; simulate; need to erase 111 4.0
fodelsedagsmemorisering fodelsedagsmemorisering 2.3j, Balanced BST (map) use map; sorted output 289 1.8
hardwoodspecies hardwoodspecies 2.3j, Balanced BST (map) use map; sorted output; also available at UVa 10226 - Hardwood Species 378 2.7
kattissquest kattissquest 2.3j, Balanced BST (map) use map of priority queues; other solutions exist 834 3.1
maeting maeting 2.3j, Balanced BST (map) map name to frequencies; sort in non-increasing order 433 1.6
notamused notamused 2.3j, Balanced BST (map) use map; sorted output 601 2.0
opensource opensource 2.3j, Balanced BST (map) use map and set to check previous strings; order needed; also available at UVa 11239 - Open Source 291 3.3
problemclassification problemclassification 2.3j, Balanced BST (map) mapper; frequency counting 345 3.1
srednji srednji 2.3j, Balanced BST (map) go left and right of B; use fast data structure like map to help determine the result fast 164 4.1
warehouse warehouse 2.3j, Balanced BST (map) use unordered_map and multimap 920 2.1
zoo zoo 2.3j, Balanced BST (map) parsing; keep last token; tolower; frequency counting with map; order needed 1499 1.7
10909 Fetching from uHunt 2.3k, Order Statistics Tree involves dynamic selection; use pb\_ds, Fenwick Tree, or augment balanced BST 0.0
babynames babynames 2.3k, Order Statistics Tree dynamic rank problem; use two pb_ds 87 5.5
continuousmedian continuousmedian 2.3k, Order Statistics Tree dynamic selection problem; specifically the median values; pb_ds helps 140 3.9
cookieselection cookieselection 2.3k, Order Statistics Tree map large integers to up to 600K integers; use pb_ds or Fenwick Tree and the select(median) operation of Fenwick Tree 923 4.3
gcpc gcpc 2.3k, Order Statistics Tree dynamic rank problem; pb_ds helps 876 5.3
lc0295 to replace with LeetCode link soon... 2.3k, Order Statistics Tree dynamic median selection; pb_ds; similar to Kattis - continousmedian; top-100-liked; top-interview-150 0 6.0
lc0094 to replace with LeetCode link soon... 2.3l, BT Exercises, E simulate inorder traversal; top-100-liked 0 2.0
lc0100 to replace with LeetCode link soon... 2.3l, BT Exercises, E recursive check; top-interview-150 0 2.0
lc0101 to replace with LeetCode link soon... 2.3l, BT Exercises, E two pointers; check if the mirror traversal are identical; top-100-liked; top-interview-150 0 2.0
lc0104 to replace with LeetCode link soon... 2.3l, BT Exercises, E recursive height check; leetcode-75; top-100-liked; top-interview-150 0 2.0
lc0110 to replace with LeetCode link soon... 2.3l, BT Exercises, E for each vertex, check its height of left and right subtrees and compare 0 2.0
lc0112 to replace with LeetCode link soon... 2.3l, BT Exercises, E recursive preorder check; top-interview-150 0 2.0
lc0114 to replace with LeetCode link soon... 2.3l, BT Exercises, E preorder traversal; reconstruct answer as requested; top-100-liked; top-interview-150 0 4.0
lc0129 to replace with LeetCode link soon... 2.3l, BT Exercises, E preorder; process leaves; top-interview-150 0 4.0
lc0144 to replace with LeetCode link soon... 2.3l, BT Exercises, E simulate preorder traversal 0 2.0
lc0145 to replace with LeetCode link soon... 2.3l, BT Exercises, E simulate postorder traversal 0 2.0
lc0173 to replace with LeetCode link soon... 2.3l, BT Exercises, E do inorder traversal; convert into array; keep current next index of array 0 4.0
lc0222 to replace with LeetCode link soon... 2.3l, BT Exercises, E go to the rightmost vertex; if it has a left child, go left once; top-interview-150 0 2.0
lc0226 to replace with LeetCode link soon... 2.3l, BT Exercises, E swap left and right pointers, recursively; top-100-liked; top-interview-150 0 2.0
lc0235 to replace with LeetCode link soon... 2.3l, BT Exercises, E can be solved with LC 0236 solution too 0 4.0
lc0236 to replace with LeetCode link soon... 2.3l, BT Exercises, E find the first vertex using postorder where both p and q are seen; leetcode-75; top-100-liked; top-interview-150 0 4.0
lc0257 to replace with LeetCode link soon... 2.3l, BT Exercises, E preorder traversal; remember the paths 0 2.0
lc0298 to replace with LeetCode link soon... 2.3l, BT Exercises, E PREMIUM - hint hidden 0 4.0
lc0366 to replace with LeetCode link soon... 2.3l, BT Exercises, E PREMIUM - hint hidden 0 4.0
lc0437 to replace with LeetCode link soon... 2.3l, BT Exercises, E for each vertex, run preorder traversal; check if the path sum equals to target; leetcode-75; top-100-liked 0 4.0
lc0543 to replace with LeetCode link soon... 2.3l, BT Exercises, E n is small enough; take the maximum sum of height of left+right subtrees, for all subtrees; top-100-liked 0 2.0
lc0559 to replace with LeetCode link soon... 2.3l, BT Exercises, E compute the height of n-ary tree 0 2.0
lc0563 to replace with LeetCode link soon... 2.3l, BT Exercises, E modify postorder traversal a bit to compute the tilt 0 2.0
lc0572 to replace with LeetCode link soon... 2.3l, BT Exercises, E n is small enough; for each subtree of root, we can test if it is an identical tree with subroot 0 2.0
lc0589 to replace with LeetCode link soon... 2.3l, BT Exercises, E extension of LC 0144; on n-ary tree 0 2.0
lc0590 to replace with LeetCode link soon... 2.3l, BT Exercises, E extension of LC 0145; on n-ary tree 0 2.0
lc0654 to replace with LeetCode link soon... 2.3l, BT Exercises, E find the location of the max; recursively build the binary tree 0 4.0
lc0671 to replace with LeetCode link soon... 2.3l, BT Exercises, E preorder; just do as asked 0 2.0
lc0814 to replace with LeetCode link soon... 2.3l, BT Exercises, E do postorder traversal; if the subtree has all zeroes; remove it 0 4.0
lc0872 to replace with LeetCode link soon... 2.3l, BT Exercises, E run inorder traversals on both trees; picking only the leaves; compare them; leetcode-75 0 2.0
lc0965 to replace with LeetCode link soon... 2.3l, BT Exercises, E recursive check if all values in the tree is the same 0 2.0
lc0988 to replace with LeetCode link soon... 2.3l, BT Exercises, E preorder; keep path; reverse 0 4.0
lc0993 to replace with LeetCode link soon... 2.3l, BT Exercises, E customize binary tree traversal to also compute depth 0 2.0
lc1372 to replace with LeetCode link soon... 2.3l, BT Exercises, E modified preorder traversal; reset counter if same direction; add counter if zig-zag-ing; leetcode-75 0 4.0
lc1379 to replace with LeetCode link soon... 2.3l, BT Exercises, E run inorder traversal on both trees simultaneously 0 2.0
lc1448 to replace with LeetCode link soon... 2.3l, BT Exercises, E modified preorder traversal; keep the largest along the way; leetcode-75 0 4.0
lc2236 to replace with LeetCode link soon... 2.3l, BT Exercises, E trivial check 0 2.0
lc2265 to replace with LeetCode link soon... 2.3l, BT Exercises, E n is small enough; for each subtree of root, compute sum of values and number of vertices in that subtree 0 4.0
lc2331 to replace with LeetCode link soon... 2.3l, BT Exercises, E postorder custom traversal on Boolean binary tree 0 2.0
lc0098 to replace with LeetCode link soon... 2.3m, BST Exercises recursive BST property validator; top-100-liked; top-interview-150 0 4.0
lc0108 to replace with LeetCode link soon... 2.3m, BST Exercises recursively insert the median of the sorted array; top-100-liked; top-interview-150 0 2.0
lc0230 to replace with LeetCode link soon... 2.3m, BST Exercises inorder traversal; report the k-th element; top-100-liked; top-interview-150 0 4.0
lc0255 to replace with LeetCode link soon... 2.3m, BST Exercises PREMIUM - hint hidden 0 4.0
lc0285 to replace with LeetCode link soon... 2.3m, BST Exercises PREMIUM - hint hidden 0 4.0
lc0333 to replace with LeetCode link soon... 2.3m, BST Exercises PREMIUM - hint hidden 0 4.0
lc0426 to replace with LeetCode link soon... 2.3m, BST Exercises PREMIUM - hint hidden 0 4.0
lc0450 to replace with LeetCode link soon... 2.3m, BST Exercises code BST deletion sub-cases; leetcode-75 0 4.0
lc0501 to replace with LeetCode link soon... 2.3m, BST Exercises run inorder traversal; use Counter; output the mode(s) 0 2.0
lc0530 to replace with LeetCode link soon... 2.3m, BST Exercises the min gap is between successive elements during inorder traversal; same as LC 0783; top-interview-150 0 2.0
lc0700 to replace with LeetCode link soon... 2.3m, BST Exercises the classic BST search process; leetcode-75 0 2.0
lc0783 to replace with LeetCode link soon... 2.3m, BST Exercises the minimum gap is between successive elements found during inorder traversal; same as LC 0530 0 2.0
lc0897 to replace with LeetCode link soon... 2.3m, BST Exercises create new skewed BST using inorder traversal of original BST 0 2.0
lc0938 to replace with LeetCode link soon... 2.3m, BST Exercises customize inorder traversal of BST 0 2.0
lc1038 to replace with LeetCode link soon... 2.3m, BST Exercises run reverse Inorder traversal; cumulative sum 0 4.0
00599 Fetching from uHunt 2.4a, Graph Data Structures V-E = number of CCs; use a bitset of size 26 to count the number of vertices that have some edge 0.0
10895 Fetching from uHunt 2.4a, Graph Data Structures transpose adjacency list 0.0
10928 Fetching from uHunt 2.4a, Graph Data Structures counting out-degrees 0.0
11550 Fetching from uHunt 2.4a, Graph Data Structures graph representation; incidence matrix 0.0
11991 Fetching from uHunt 2.4a, Graph Data Structures Adjacency List 0.0
abinitio abinitio 2.4a, Graph Data Structures combo: EL input, AM as working graph DS, AL output (in hash format); all operations must be O(V) or better 104 7.3
alphabetanimals alphabetanimals 2.4a, Graph Data Structures somewhat an Adjacency List data structure 478 3.4
chopwood chopwood 2.4a, Graph Data Structures Prüfer sequence; use priority_queue 258 3.5
cutthenegativity cutthenegativity 2.4a, Graph Data Structures AM to EL conversion 1213 1.4
flyingsafely flyingsafely 2.4a, Graph Data Structures trivial solution exists 1421 1.7
hermits hermits 2.4a, Graph Data Structures a simple Graph Data Structure application question 98 3.2
illuminatispotti illuminatispotti 2.4a, Graph Data Structures store the graph in an Adjacency Matrix; O(N^3) try-all possible triangles 30 4.3
lc0133 to replace with LeetCode link soon... 2.4a, Graph Data Structures clone AL; use hashtable to ensure we only create each node once; top-interview-150 0 4.0
lc1615 to replace with LeetCode link soon... 2.4a, Graph Data Structures network rank of (u, v) = degree[u] + degree[v] - has_edge(u, v); try all pairs 0 4.0
popularitycontest popularitycontest 2.4a, Graph Data Structures a simple graph DS problem 107 2.0
railroad railroad 2.4a, Graph Data Structures do as asked; graph DS modification; bypass vertices with degree 2 95 6.3
traveltheskies traveltheskies 2.4a, Graph Data Structures (graph) DS manipulation; an array of ALs (one per each day); simulate the number of people day by day 188 3.2
tripplanning tripplanning 2.4a, Graph Data Structures use unordered_map to map bidirectional edges into 1-based indices; simulate the linear journey 232 2.4
weakvertices weakvertices 2.4a, Graph Data Structures graph edge existence checks 1775 1.5
00793 Fetching from uHunt 2.4b, Union-Find trivial; application of disjoint sets 0.0
01197 Fetching from uHunt 2.4b, Union-Find LA 2817 - Kaohsiung03; Connected Components 0.0
01329 Fetching from uHunt 2.4b, Union-Find LA 3027 - SouthEasternEurope04; interesting UFDS variant; modify the union and find routine 0.0
10158 Fetching from uHunt 2.4b, Union-Find advanced usage of disjoint sets with a nice twist; memorize list of enemies 0.0
10227 Fetching from uHunt 2.4b, Union-Find merge two disjoint sets if they are consistent; also available at Kattis - forests 0.0
10507 Fetching from uHunt 2.4b, Union-Find disjoint sets simplifies this problem 0.0
10583 Fetching from uHunt 2.4b, Union-Find count disjoint sets after all unions 0.0
10608 Fetching from uHunt 2.4b, Union-Find find the set with the largest element 0.0
10685 Fetching from uHunt 2.4b, Union-Find find the set with the largest element 0.0
11503 Fetching from uHunt 2.4b, Union-Find maintain set attribute (size) in rep item; also available at Kattis - virtualfriends 0.0
11690 Fetching from uHunt 2.4b, Union-Find check if total money from each member is 0 0.0
11987 Fetching from uHunt 2.4b, Union-Find maintain set attribute (size and sum) in rep item; new operation: move; key idea: do not destroy the parent array struct... 0.0
almostunionfind almostunionfind 2.4b, Union-Find new operation: move; idea: do not destroy the parent array structure; also available at UVa 11987 - Almost Union-Find 618 7.0
bridgesandtunnels bridgesandtunnels 2.4b, Union-Find map buildings to integer IDs; UFDS; size of set 57 3.2
chatter chatter 2.4b, Union-Find UFDS simulation using random number generation 59 3.1
control control 2.4b, Union-Find LA 7480 - Singapore15; simulation of UFDS; size of set; number of disjoint sets 424 4.6
forests forests 2.4b, Union-Find merge two disjoint sets if they are consistent; also available at UVa 10227 - Forests 127 3.0
ladice ladice 2.4b, Union-Find size of set; decrement one per usage 615 2.8
more10 more10 2.4b, Union-Find UFDS; a bit of string processing; tedious 94 7.1
skolavslutningen skolavslutningen 2.4b, Union-Find group classes that share the same column into the same CC; report number of CCs 152 1.9
swaptosort swaptosort 2.4b, Union-Find it boils down to finding CCs of 1 with N-1; 2 with N-2; and so on... 423 3.9
tildes tildes 2.4b, Union-Find basic UFDS with size of set query 165 2.6
unionfind unionfind 2.4b, Union-Find basic UFDS; similar to UVa 00793 1086 4.8
virtualfriends virtualfriends 2.4b, Union-Find maintain set attribute (size) in rep item; also available at UVa 11503 - Virtual Friends 1078 3.9
00297 Fetching from uHunt 2.4c, Tree-related DS simple quadtree problem 0.0
01232 Fetching from uHunt 2.4c, Tree-related DS LA 4108 - Singapore07; we have to use a Segment Tree; note that this problem is not about RSQ/RMQ 0.0
01513 Fetching from uHunt 2.4c, Tree-related DS LA 5902 - NorthWesternEurope11; not stack but dynamic RSQ problem; use DAT (for mapping) and Fenwick Tree (for RSQ); als... 0.0
11235 Fetching from uHunt 2.4c, Tree-related DS range maximum query 0.0
11297 Fetching from uHunt 2.4c, Tree-related DS Quad Tree with updates or use 2D segment tree 0.0
11350 Fetching from uHunt 2.4c, Tree-related DS simple tree data structure question 0.0
11402 Fetching from uHunt 2.4c, Tree-related DS Segment Tree with lazy updates 0.0
11423 Fetching from uHunt 2.4c, Tree-related DS clever usage of Fenwick Tree and large array; important hint: look at the constraints carefully 0.0
12086 Fetching from uHunt 2.4c, Tree-related DS LA 2191 - Dhaka06; pure dynamic RSQ problem; solvable with Fenwick Tree or Segment Tree 0.0
12299 Fetching from uHunt 2.4c, Tree-related DS Segment Tree with a few point (not range) updates; RMQs 0.0
12532 Fetching from uHunt 2.4c, Tree-related DS clever usage of Fenwick/Segment Tree 0.0
fenwick fenwick 2.4c, Tree-related DS basic Fenwick Tree; use long long 695 4.5
justforsidekicks justforsidekicks 2.4c, Tree-related DS use six Fenwick Trees, one for each gem type 359 3.8
lc0253 to replace with LeetCode link soon... 2.4c, Tree-related DS PREMIUM - hint hidden 0 4.0
moviecollection moviecollection 2.4c, Tree-related DS LA 5902 - NorthWesternEurope11; not a stack but a dynamic RSQ problem; also available at UVa 01513 - Movie collection 547 5.5
supercomputer supercomputer 2.4c, Tree-related DS easy problem if we use Fenwick Tree 760 3.8
turbo turbo 2.4c, Tree-related DS somewhat similar with UVa 01513/Kattis - moviecollection; use DAT (for mapping) and Fenwick Tree (for RSQ) 507 4.3
worstweather worstweather 2.4c, Tree-related DS store the year+rain data in a (sorted) array; binary search; Segment Tree/Sparse Table: static RMaxQueries 118 7.7

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