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Note that we only update DACU column manually when we first entered the hint (thus an outdated data).

As Kattis users, you can also sort these problems based Kattis points (usually correlated with DACU but not always).
Generally, problems with low Kattis points are the easier problems.
Note that we only update Point column manually (not a live data).

For Kattis and Google Chrome users, install Kattis Hint Giver created by one of my student Lin Si Jie that integrates this page directly with Kattis problems pages (Kattis has major UI/UX upgrade on early Jun 2022, Si Jie has updated this tool and added 'spoiler blur' so users can decide when to be spoiled; but Kattis changes its UI again by end 2023 so this feature is now broken again)
(Almost) all of the easiest 1097 problems (range: [1.1..3.3] points, average at 2.2 points) have hints and solving them all gives you 1097*~2.2 ≥ 2413.4 total Kattis points — The Lower Bound of Programming Contests in the 2020s year 2024.
Tips: You may want to occasionally 'Remove 'Kattis Hint Giver' from Chrome' and re-'Add it back to Chrome' to manually sync this Methods to Solve content with the local cache.

Kattis Problem Title CP4+5 Hint DACU Point
addtwonumbers addtwonumbers 1.4a, One-Liner I/O just sum the two input integers 3953 1.2
ameriskur ameriskur 1.4a, One-Liner I/O just print n*0.09144 2275 1.3
bergmal bergmal 1.4a, One-Liner I/O simply echo the input 740 1.2
bitteeinbit bitteeinbit 1.4a, One-Liner I/O just print the first char of the input 273 1.3
carrots carrots 1.4a, One-Liner I/O just print P 15155 1.3
decimaldeletion decimaldeletion 1.4a, One-Liner I/O x.5 can be rounded up or down 67 1.7
digitswap digitswap 1.4a, One-Liner I/O read the 2-digits input; print in reverse 1227 1.3
dragafra dragafra 1.4a, One-Liner I/O output n-m 1327 1.1
echoechoecho echoechoecho 1.4a, One-Liner I/O re-print the input 3x 1654 1.2
fifa fifa 1.4a, One-Liner I/O just output 2022+n//m (round down) 2348 1.2
fimmtudagstilbod fimmtudagstilbod 1.4a, One-Liner I/O one-liner formula or simple selection 544 1.5
flatbokuveisla flatbokuveisla 1.4a, One-Liner I/O just print n mod m 942 1.2
flytibaka flytibaka 1.4a, One-Liner I/O just do nothing (e.g., submit a blank Python code) 688 1.4
greetings2 greetings2 1.4a, One-Liner I/O just reprint the input as requested 589 1.3
hello hello 1.4a, One-Liner I/O just print "Hello World!" 39217 1.2
heroesofvelmar heroesofvelmar 1.4a, One-Liner I/O ad hoc card game; use the attached .json for the details; 3 cards have special cases 237 1.9
kvedja kvedja 1.4a, One-Liner I/O print 'Kvedja,\n' and the input name 960 1.2
leggjasaman leggjasaman 1.4a, One-Liner I/O just output n+m 6564 1.1
lubbilaerir lubbilaerir 1.4a, One-Liner I/O print the first character of the input 1128 1.1
metronome metronome 1.4a, One-Liner I/O just divide by 4.0 1614 1.3
ovissa ovissa 1.4a, One-Liner I/O just output the length of input string 6088 1.2
planina planina 1.4a, One-Liner I/O just print (2^N+1)^2; OEIS A028400 5965 1.3
romans romans 1.4a, One-Liner I/O just print round(X * 1087.7626) 2088 1.4
shortcuttowhat shortcuttowhat 1.4a, One-Liner I/O just print (n+5)*3-10 1979 1.2
skeytasaman skeytasaman 1.4a, One-Liner I/O just print the two input lines in one line 203 1.4
thelastproblem thelastproblem 1.4a, One-Liner I/O S can have space(s) 76 1.8
tilhamingju tilhamingju 1.4a, One-Liner I/O just print the sentence as asked 1348 1.1
tolvunarfraedingartelja tolvunarfraedingartelja 1.4a, One-Liner I/O just print n-1 1312 1.2
twosum twosum 1.4a, One-Liner I/O another a+b problem 1540 1.4
velkomin velkomin 1.4a, One-Liner I/O just print 'VELKOMIN!' 6081 1.1
vidsnuningur vidsnuningur 1.4a, One-Liner I/O just output the reverse of input string 2570 1.2
aleidibio aleidibio 1.4b, I/O + Sequences Only just output c-(a+b) 1233 1.2
betting betting 1.4b, I/O + Sequences Only simple probability formula 788 1.2
bladra2 bladra2 1.4b, I/O + Sequences Only use the given Physics formula 935 1.2
ekkidaudi ekkidaudi 1.4b, I/O + Sequences Only simply reformat the input 910 1.5
faktor faktor 1.4b, I/O + Sequences Only just print (I-1)*A+1 8022 1.2
gcvwr gcvwr 1.4b, I/O + Sequences Only simple math 236 1.3
jackolanternjuxtaposition jackolanternjuxtaposition 1.4b, I/O + Sequences Only just print N*T*M 53 1.7
r2 r2 1.4b, I/O + Sequences Only just print 2*S-R1 14929 1.2
shandy shandy 1.4b, I/O + Sequences Only just print min(B, L) * 2 267 1.3
titlecost titlecost 1.4b, I/O + Sequences Only take the min of length of s vs c 500 1.6
addingtrouble addingtrouble 1.4c, Selection Only, 2 Cases just check if A+B == C 3686 1.3
blandadbest blandadbest 1.4c, Selection Only, 2 Cases 2 cases 833 1.2
blueberrywaffle blueberrywaffle 1.4c, Selection Only, 2 Cases formula with rounding; 2 cases 716 1.9
canadianseh canadianseh 1.4c, Selection Only, 2 Cases just check the last three characters 771 1.5
chardonnay chardonnay 1.4c, Selection Only, 2 Cases 2 cases (0 and 7 versus 1 to 6) 366 1.4
conteststruggles conteststruggles 1.4c, Selection Only, 2 Cases simple formula; check if answer in [0..100] 729 2.2
fyi fyi 1.4c, Selection Only, 2 Cases 2 cases; output 1/0 if the input starts with '555'/not, respectively 90 1.6
ginfizz ginfizz 1.4c, Selection Only, 2 Cases 2 printout cases; slice vs slices 313 1.4
heysata heysata 1.4c, Selection Only, 2 Cases 2 cases 436 1.3
hradgreining hradgreining 1.4c, Selection Only, 2 Cases if-else; 2 cases 2253 1.3
hvertskalmaeta hvertskalmaeta 1.4c, Selection Only, 2 Cases only 3 municipalities go to 'Akureyri' 383 1.5
isithalloween isithalloween 1.4c, Selection Only, 2 Cases if-else; 2 cases 3761 1.3
laptopsticker laptopsticker 1.4c, Selection Only, 2 Cases if-else; 2 cases; note: one centimeter for both sides 3329 1.5
mergjadmal mergjadmal 1.4c, Selection Only, 2 Cases 2 cases 262 1.5
millifaersla millifaersla 1.4c, Selection Only, 2 Cases pick the smallest among the three 939 1.2
mork mork 1.4c, Selection Only, 2 Cases 2 cases; but there are 2 sub-cases for Jebb 110 2.1
moscowdream moscowdream 1.4c, Selection Only, 2 Cases if-else; 2 cases; check n ≥ 3 3902 1.8
skak skak 1.4c, Selection Only, 2 Cases only 2 cases; think about it 951 1.3
sorttwonumbers sorttwonumbers 1.4c, Selection Only, 2 Cases swap a and b if a > b 1313 1.4
storafmaeli storafmaeli 1.4c, Selection Only, 2 Cases divisibility by 10 test; 2 cases 3520 1.2
vajningsplikt vajningsplikt 1.4c, Selection Only, 2 Cases selection; multiple cases; be careful 788 2.1
whichisgreater whichisgreater 1.4c, Selection Only, 2 Cases if-else; 2 cases 2253 1.3
grading grading 1.4d, Selection Only, 3+ Cases 6 cases 2744 1.5
internationaldates internationaldates 1.4d, Selection Only, 3+ Cases 3 cases 1307 1.5
judgingmoose judgingmoose 1.4d, Selection Only, 3+ Cases 4 cases 9391 1.5
kikiboba kikiboba 1.4d, Selection Only, 3+ Cases 4 cases 2691 1.3
onechicken onechicken 1.4d, Selection Only, 3+ Cases 4 cases; piece vs pieces 6464 1.6
provincesandgold provincesandgold 1.4d, Selection Only, 3+ Cases 6 cases 4756 1.4
quadrant quadrant 1.4d, Selection Only, 3+ Cases 4 cases 33326 1.2
sith sith 1.4d, Selection Only, 3+ Cases 3 cases 1137 1.6
stafur stafur 1.4d, Selection Only, 3+ Cases 3 cases; be-careful with 'Y' 794 1.6
takkar takkar 1.4d, Selection Only, 3+ Cases 3 cases 2003 1.2
temperature temperature 1.4d, Selection Only, 3+ Cases 3 cases; derive formula 1776 2.2
testdrive testdrive 1.4d, Selection Only, 3+ Cases 4 cases 848 2.1
undeadoralive undeadoralive 1.4d, Selection Only, 3+ Cases 4 cases 2319 1.4
averagecharacter averagecharacter 1.4e, Repetition Only sum ASCII values of all characters; divide by the number of characters 365 1.6
codetosavelives codetosavelives 1.4e, Repetition Only repeat t times; convert to ints; sum; convert to digits again 238 1.5
cosmicpathoptimization cosmicpathoptimization 1.4e, Repetition Only ignore the long text; just find the average temperature of M planets 410 1.5
curvespeed curvespeed 1.4e, Repetition Only for each test case, just apply the formula 128 2.8
different different 1.4e, Repetition Only use abs function per test case 8964 2.3
hipphipp hipphipp 1.4e, Repetition Only print 'Hipp hipp hurra!' twenty times 9053 1.1
hipphipphurra hipphipphurra 1.4e, Repetition Only print 'Hipp hipp hurra, {name}', x times 735 1.3
inputscandal inputscandal 1.4e, Repetition Only read all lines first; print total lines; echo all lines 15 3.0
jumbojavelin jumbojavelin 1.4e, Repetition Only sum and offset by (N-1) 112 1.5
nsum nsum 1.4e, Repetition Only just sum the content of the small list 1406 1.3
qaly qaly 1.4e, Repetition Only trivial loop 5955 1.2
ratingproblems ratingproblems 1.4e, Repetition Only loop to sum the ratings; simple formula afterwards 2227 1.3
reduplikation reduplikation 1.4e, Repetition Only repeat s as the digit indicates 3273 1.2
takkfyrirmig takkfyrirmig 1.4e, Repetition Only loop n times; echo the names 769 1.2
tarifa tarifa 1.4e, Repetition Only one pass; array not needed 9768 1.3
telja telja 1.4e, Repetition Only simple loop 691 1.2
timeloop timeloop 1.4e, Repetition Only just print 'num Abracadabra' N times 17170 1.3
umferd umferd 1.4e, Repetition Only loop; count the dots 461 1.4
astrologicalsign astrologicalsign 1.4f, Multiple TC + Selection 12 cases (Capricorn is a bit different) 226 1.6
eligibility eligibility 1.4f, Multiple TC + Selection 3 cases 1741 1.6
helpaphd helpaphd 1.4f, Multiple TC + Selection 2 cases 2044 1.6
leftbeehind leftbeehind 1.4f, Multiple TC + Selection 4 cases 2014 1.6
lessvsfewer lessvsfewer 1.4f, Multiple TC + Selection case analysis; multiple test cases 375 2.1
nastyhacks nastyhacks 1.4f, Multiple TC + Selection 3 cases 6308 1.3
numberfun numberfun 1.4f, Multiple TC + Selection 2 cases (out of 6 combinations; addition/multiplication are commutative); remember integer division 3436 1.4
oddities oddities 1.4f, Multiple TC + Selection 2 cases 11523 1.3
vedurheidar vedurheidar 1.4f, Multiple TC + Selection simple selection over n test cases 809 1.4
bestagjofin bestagjofin 1.4g, Control Flow, Level 1 loop; keep track of the gift with maximum fun 796 1.3
biladlyklabord biladlyklabord 1.4g, Control Flow, Level 1 one pass; ignore adjacent duplicate characters 258 1.6
callforproblems callforproblems 1.4g, Control Flow, Level 1 count number of odd difficulty ratings 1526 1.3
cold cold 1.4g, Control Flow, Level 1 linear pass; array not really needed 12609 1.3
divvyingup divvyingup 1.4g, Control Flow, Level 1 sum; simple if-else 406 1.6
fjoldibokstafa fjoldibokstafa 1.4g, Control Flow, Level 1 count azAZ letters in the input; one-liner is possible 608 1.4
fyrirtaekjanafn fyrirtaekjanafn 1.4g, Control Flow, Level 1 one pass; only keep the vowels (including 'y') 510 1.8
goombastacks goombastacks 1.4g, Control Flow, Level 1 just stack all the goombas and check 437 1.5
isyavowel isyavowel 1.4g, Control Flow, Level 1 count the occurrences of 'aeiou' vs 'aeiouy' in the input 735 1.2
jobexpenses jobexpenses 1.4g, Control Flow, Level 1 simple loop 1427 1.4
licensetolaunch licensetolaunch 1.4g, Control Flow, Level 1 easy linear pass 1969 1.4
oddecho oddecho 1.4g, Control Flow, Level 1 just do as asked 1466 1.3
offworldrecords offworldrecords 1.4g, Control Flow, Level 1 check as required 150 1.8
skammstofun skammstofun 1.4g, Control Flow, Level 1 take first character of each word if it is in Uppercase 360 1.5
skruop skruop 1.4g, Control Flow, Level 1 simple control flow 254 1.5
spritt spritt 1.4g, Control Flow, Level 1 simple loop and selection 1415 1.4
tornbygge tornbygge 1.4g, Control Flow, Level 1 linear pass 272 1.8
training training 1.4g, Control Flow, Level 1 one pass and check 527 1.5
triplesevens triplesevens 1.4g, Control Flow, Level 1 check if there is 7 in all three wheels 924 1.4
busassignment busassignment 1.4h, Control Flow, Level 2 one pass 79 1.8
pobudget pobudget 1.4h, Control Flow, Level 2 simple control flow 159 1.4
sottkvi sottkvi 1.4h, Control Flow, Level 2 simple control flow 404 1.5
babybites babybites 1.4i, Control Flow, Level 3 easy simulation 1624 1.7
cinema2 cinema2 1.4i, Control Flow, Level 3 just a small variation from Kattis - cinema 181 1.8
earlywinter earlywinter 1.4i, Control Flow, Level 3 linear pass 543 1.9
electionparadox electionparadox 1.4i, Control Flow, Level 3 simple control flow 212 1.9
fadingwind fadingwind 1.4i, Control Flow, Level 3 just code as instructed 866 1.5
mylla mylla 1.4i, Control Flow, Level 3 simulation 151 1.6
oddgnome oddgnome 1.4i, Control Flow, Level 3 linear pass 2388 1.6
smil smil 1.4i, Control Flow, Level 3 simple loop; test up to 4 patterns 1081 1.4
speeding speeding 1.4i, Control Flow, Level 3 just loop; keep the running max 84 1.4
speedlimit speedlimit 1.4i, Control Flow, Level 3 standard simulation problem 7164 1.4
stararrangements stararrangements 1.4i, Control Flow, Level 3 one loop 1637 1.4
statistics statistics 1.4i, Control Flow, Level 3 one pass; array not needed 2942 1.7
vedurvindhradi vedurvindhradi 1.4i, Control Flow, Level 3 13 cases; easier to check with array and loop 316 1.6
zanzibar zanzibar 1.4i, Control Flow, Level 3 one pass; array not needed 2308 1.5
abc abc 1.4j, Function sort 3 numbers into ABC; then print output as needed 5282 1.8
arithmeticfunctions arithmeticfunctions 1.4j, Function implement the three functions as asked 140 1.7
artichoke artichoke 1.4j, Function LA 7150 - WorldFinals Marrakech15; linear scan; probably one of the easiest WorldFinals problem; also available at UVa 0... 1390 2.8
bidendalausbid bidendalausbid 1.4j, Function convert HH:MM to minutes; offset 24*60 minutes for past midnight cases 338 2.5
chugging chugging 1.4j, Function abstract the computation of drinking time as function; compute for Alice and for Bob; decide accordingly 211 1.6
combinationlock combinationlock 1.4j, Function simple; do as asked; also available at UVa 10550 - Combination Lock 633 2.5
digits digits 1.4j, Function direct simulation; also available at UVa 11687 - Digits 214 3.5
equalshots equalshots 1.4j, Function use a function to compute the alcohol content of each shot 373 1.3
filip filip 1.4j, Function create a 'reverse string' function; then if-else check 6345 1.3
logicfunctions logicfunctions 1.4j, Function implement the three simple logical Boolean operations 62 2.5
mia mia 1.4j, Function just if-else check 1136 2.1
sifferprodukt sifferprodukt 1.4j, Function easy digit product function 460 1.5
socialdistancing2 socialdistancing2 1.4j, Function 1D Boolean array of occupied seats; find 3 adjacent empty seats 188 1.9
treasurehunt treasurehunt 1.4j, Function simple simulation on 2D grid 1006 2.6
acm acm 1.4k, 1D Array, Easier simple simulation; one pass 3526 1.5
airfaregrants airfaregrants 1.4k, 1D Array, Easier min(P)-max(P)/2; minimally 0 599 1.3
aldur aldur 1.4k, 1D Array, Easier find the minimum of a list of integers 512 1.3
atlogur atlogur 1.4k, 1D Array, Easier easy simulation; use 2 arrays or 1 array of pairs 134 2.4
barcelona barcelona 1.4k, 1D Array, Easier find the index of k in a 495 1.3
basketballoneonone basketballoneonone 1.4k, 1D Array, Easier linear pass 957 1.6
cetiri cetiri 1.4k, 1D Array, Easier sort 3 number helps; 3 cases 1165 1.9
champernowneverification champernowneverification 1.4k, 1D Array, Easier there are only 9 Champernowne words 752 1.5
coffeecupcombo coffeecupcombo 1.4k, 1D Array, Easier greedily purchase two cups upon encountering a coffee machine 849 1.6
cutinline cutinline 1.4k, 1D Array, Easier a simple list ADT problem (small N) 96 2.2
dagatal dagatal 1.4k, 1D Array, Easier simple array of 12 integers 1347 1.2
forcedchoice forcedchoice 1.4k, 1D Array, Easier simple in-small-array test 205 1.3
hitastig hitastig 1.4k, 1D Array, Easier get min and max of an array 395 1.6
hothike hothike 1.4k, 1D Array, Easier one pass; using array helps a bit 835 1.7
kakor kakor 1.4k, 1D Array, Easier sum array A 153 1.6
lineup lineup 1.4k, 1D Array, Easier sort ascending/descending and compare; or linear pass 3703 1.6
lostlineup lostlineup 1.4k, 1D Array, Easier simple 1D array manipulation 550 1.5
meanwords meanwords 1.4k, 1D Array, Easier use array of strings 403 1.7
ofugsnuid ofugsnuid 1.4k, 1D Array, Easier simple list reversal problem; one liner with Python 636 1.4
peningar peningar 1.4k, 1D Array, Easier circular array; a bit of modular arithmetic; avoid cycle 428 2.2
trainboarding trainboarding 1.4k, 1D Array, Easier simulation with arrays 58 3.0
vectorfunctions vectorfunctions 1.4k, 1D Array, Easier a good tutorial problem involving C++ std::vector functions 70 2.1
vefthjonatjon vefthjonatjon 1.4k, 1D Array, Easier use counter array of size 3; loop; find min 908 1.6
zoom zoom 1.4k, 1D Array, Easier store in 1D array; access indices that are multiples of k 302 1.6
hakkari hakkari 1.4l, 2D Array, Easier find indices of the '*' 659 1.3
armystrengtheasy armystrengtheasy 1.4m, Easy also see Kattis - armystrengthhard 1585 2.1
armystrengthhard armystrengthhard 1.4m, Easy also see Kattis - armystrengtheasy; re-read the problem statement several times to unveil a trivial solution 1466 2.2
batterup batterup 1.4m, Easy easy one loop 4542 1.3
brokenswords brokenswords 1.4m, Easy easy counting problem 367 1.7
cinema cinema 1.4m, Easy easy simulation 129 2.6
dontfalldownstairs dontfalldownstairs 1.4m, Easy easy linear pass check 114 2.2
doublepassword doublepassword 1.4m, Easy two to the power of number of different digits 608 1.4
drinkingsong drinkingsong 1.4m, Easy just one loop; but be careful of with the grammar 336 2.4
findingana findingana 1.4m, Easy simple string search/find operation 424 1.3
hairofthedog hairofthedog 1.4m, Easy find adjacent sober-drunk sequence 412 1.3
hangingout hangingout 1.4m, Easy simple loop 2218 1.3
haughtycuisine haughtycuisine 1.4m, Easy just remember the last one 390 1.6
hissingmicrophone hissingmicrophone 1.4m, Easy simple loop 7690 1.3
keysphonewallet keysphonewallet 1.4m, Easy check 3 specific items from a short list 740 1.3
kinahvisl kinahvisl 1.4m, Easy find the difference of two strings; plus one 486 1.4
mosquito mosquito 1.4m, Easy direct simulation 822 1.9
mult mult 1.4m, Easy simple control flow 701 1.6
multiplications multiplications 1.4m, Easy multiply N integers; use long long; modular arithmetic 33 2.5
overdraft overdraft 1.4m, Easy find the lowest balance over all n transactions 356 1.7
scalingrecipe scalingrecipe 1.4m, Easy apply math scaling formula with loop; be careful of precision issue 229 1.6
stopwatch stopwatch 1.4m, Easy linear pass; simulation 390 1.3
volim volim 1.4m, Easy simple simulation 1855 1.7
waterjournal waterjournal 1.4m, Easy check if a and/or b are/is seen in the log and decide the output accordingly 577 1.7
architecture architecture 1.4n, Still Easy 2D array problem with an easy two 1D arrays solution 78 2.7
bossbattle bossbattle 1.4n, Still Easy trick question 1391 1.8
bottleopening bottleopening 1.4n, Still Easy two cases; simple construction for k < n 220 1.7
boundingrobots boundingrobots 1.4n, Still Easy maintain separate variables 1141 1.6
brokencalculator brokencalculator 1.4n, Still Easy trivial; just do as asked 13 3.7
driversdilemma driversdilemma 1.4n, Still Easy only 6 different cases; note that starting fuel is C/2 200 2.0
eventplanning eventplanning 1.4n, Still Easy just simulate; 2D loop 458 2.0
exactlyelectrical exactlyelectrical 1.4n, Still Easy Manhattan distance; waste energy at the end by moving 1 cell around target 469 2.0
eyeofsauron eyeofsauron 1.4n, Still Easy simple string check 998 1.3
flipflow flipflow 1.4n, Still Easy simulation 222 2.1
fromatob fromatob 1.4n, Still Easy we can only go up via (a bunch of) +1 move(s); we can only go down via (an optional +1 move to make even) and then divid... 44 3.1
ghostleg ghostleg 1.4n, Still Easy 1D array; simulation 772 1.4
makingameowth makingameowth 1.4n, Still Easy tricky simulation 474 1.6
missingnumbers missingnumbers 1.4n, Still Easy two linear loops; use a small array of Booleans 1622 1.7
peasoup peasoup 1.4n, Still Easy one linear pass 771 2.4
prerequisites prerequisites 1.4n, Still Easy process the requirements as the input is read; also available at UVa 10919 - Prerequisites? 284 1.9
pyramids pyramids 1.4n, Still Easy find the simple pattern to construct a pyramid of a certain height 459 1.5
sauna sauna 1.4n, Still Easy one pass; keep min and max 499 1.4
sok sok 1.4n, Still Easy case analysis 750 1.7
spacerace spacerace 1.4n, Still Easy easy control flow 140 2.2
thanos thanos 1.4n, Still Easy simple simulation; R is at least 2 2503 2.5
vote vote 1.4n, Still Easy follow the requirements 1584 2.2
anotherbrick anotherbrick 1.4o, Medium simple simulation 1424 1.9
astackofgold astackofgold 1.4o, Medium linear pass 506 1.4
babypanda babypanda 1.4o, Medium think backwards from m back to 0; n is not needed 338 2.2
basicprogramming1 basicprogramming1 1.4o, Medium a nice summative problem for programming examination of a basic programming methodology course 201 4.0
battlesimulation battlesimulation 1.4o, Medium one pass; special check on 3! = 6 possible combinations of 3 combo moves 900 2.8
beekeeper beekeeper 1.4o, Medium single loop; be careful that vowel set here includes 'y' 1025 2.7
bitsequalizer bitsequalizer 1.4o, Medium analyzing patterns; also available at UVa 12545 - Bits Equalizer 174 4.5
bottledup bottledup 1.4o, Medium find integer a and b so that a*v1 + b*v2 == s; single loop 637 2.6
climbingworm climbingworm 1.4o, Medium simulation; similar with UVa 00573 - The Snail 222 2.4
codecleanups codecleanups 1.4o, Medium a bit tricky 515 2.4
cowcrane cowcrane 1.4o, Medium reading comprehension; case analysis; eventually there are only 4 possible cases 181 3.9
deathtaxes deathtaxes 1.4o, Medium direct simulation; a bit of reading comprehension 179 3.3
guillaume guillaume 1.4o, Medium Scan from the back; avoid division by 0 73 3.3
howl howl 1.4o, Medium simply extend the input by one correct character; case analysis exercise 288 1.8
risdomare risdomare 1.4o, Medium find max of pair(A+S, A or S based on preference); or sort the pairs first 379 2.0
shatteredcake shatteredcake 1.4o, Medium sum the area of the pieces and relate it with L*W 957 1.6
snowfall snowfall 1.4o, Medium linear pass 156 1.6
warringscoring warringscoring 1.4o, Medium just do as asked; 1D array manipulation 193 3.2
cyaniderivers cyaniderivers 1.5a, 1D Character Array find longest consecutive '0's; divide by 2 274 2.2
finalexam2 finalexam2 1.5a, 1D Character Array compare array with itself (but shifted by one index) 2779 1.5
intuitiveelements intuitiveelements 1.5a, 1D Character Array check characters in string 103 1.6
kcuddlanod kcuddlanod 1.5a, 1D Character Array reverse a string (char array); replace 2 and 5; compare 337 1.8
leynithjonusta leynithjonusta 1.5a, 1D Character Array reprint input without spaces 1519 1.3
pokechat pokechat 1.5a, 1D Character Array 1D array indexing 1970 1.5
radgreining1 radgreining1 1.5a, 1D Character Array start with n unknowns; put m sequences one after another and check accordingly 376 1.6
stickykeys stickykeys 1.5a, 1D Character Array one pass check on an array of characters 1411 1.5
ullendullendoff ullendullendoff 1.5a, 1D Character Array array; extract the required index 689 1.7
conundrum conundrum 1.5b, Cipher, Easier simple cipher 5240 1.4
cypherdecypher cypherdecypher 1.5b, Cipher, Easier encrypt n messages as requested 169 1.7
drmmessages drmmessages 1.5b, Cipher, Easier simple decrypt; follow instruction 1949 1.6
drunkvigenere drunkvigenere 1.5b, Cipher, Easier simple decrypt; reverse the given instruction 189 1.5
encodedmessage encodedmessage 1.5b, Cipher, Easier simple 2D grid cipher 2316 1.4
kemija08 kemija08 1.5b, Cipher, Easier simple vowel checks 3070 1.4
keytocrypto keytocrypto 1.5b, Cipher, Easier simple decrypt 1029 1.7
reverserot reverserot 1.5b, Cipher, Easier simple cipher 2641 1.7
runlengthencodingrun runlengthencodingrun 1.5b, Cipher, Easier encode and decode 1929 1.7
t9spelling t9spelling 1.5b, Cipher, Easier similar to (the reverse of) UVa 12896 2425 1.7
anewalphabet anewalphabet 1.5c, Cipher, Medium simple cipher; 26 characters 4154 1.8
falsesecurity falsesecurity 1.5c, Cipher, Medium a bit tedious decoder problem 948 1.6
keylogger keylogger 1.5c, Cipher, Medium cipher problem; map sound to index; see sample input 1 227 2.3
permcode permcode 1.5c, Cipher, Medium reading comprehension problem 166 2.2
piglatin piglatin 1.5c, Cipher, Medium simple; check the vowels that include 'y' and process it 916 2.1
secretmessage secretmessage 1.5c, Cipher, Medium just do as asked; use 2D grid 2866 1.7
tajna tajna 1.5c, Cipher, Medium simple 2D grid cipher 471 2.1
autori autori 1.5d, Input Parsing (Iter) simple string tokenizer problem 11602 1.2
bannord bannord 1.5d, Input Parsing (Iter) parse the input against set of forbidden characters 601 1.7
freeforminput freeforminput 1.5d, Input Parsing (Iter) Texas 74; tedious parsing; simple summation 83 2.1
genealogical genealogical 1.5d, Input Parsing (Iter) iterative parser; need to be careful when trimming the tokens; do not print new line as the last line; otherwise this is... 77 3.5
headguard headguard 1.5d, Input Parsing (Iter) run length encoding 164 2.0
liquidassets liquidassets 1.5d, Input Parsing (Iter) iterative parsing; process the two rules one after another 274 3.4
mumblerap mumblerap 1.5d, Input Parsing (Iter) find the largest integer in the string 597 1.7
pervasiveheartmonitor pervasiveheartmonitor 1.5d, Input Parsing (Iter) simple parsing; then finding average 950 1.7
screen screen 1.5d, Input Parsing (Iter) there are lots of simplifying specifications that makes this problem doable, especially with Python eval(expression) 39 3.5
timebomb timebomb 1.5d, Input Parsing (Iter) just a tedious input parsing problem; divisibility by 6 1174 1.8
tripletexting tripletexting 1.5d, Input Parsing (Iter) print characters that appear at least two times out of three 56 1.8
afjormun afjormun 1.5e, Output Formatting, E format the output as requested 330 1.6
asciikassi asciikassi 1.5e, Output Formatting, E ASCII art; create 2D grid as per requirement 478 1.5
asciikassi2 asciikassi2 1.5e, Output Formatting, E ASCII art; create 2D grid as per requirement; a bit harder than asciikassi 273 2.1
display display 1.5e, Output Formatting, E unordered_map; map a digit -> enlarged 7x5 version 635 2.5
ethanol ethanol 1.5e, Output Formatting, E simple formatting 340 1.4
framvindustika framvindustika 1.5e, Output Formatting, E easy ASCII art progress bar 300 3.4
krizaljka krizaljka 1.5e, Output Formatting, E simple 2D character array formatting 483 1.8
mirror mirror 1.5e, Output Formatting, E simple 2D character array formatting 1757 1.7
mrcodeformatgrader mrcodeformatgrader 1.5e, Output Formatting, E tedious output formatting 441 2.0
multiplication multiplication 1.5e, Output Formatting, E tedious time waster output formatting problem 162 2.2
musicalnotation musicalnotation 1.5e, Output Formatting, E simple but tedious 421 2.0
okvir okvir 1.5e, Output Formatting, E simple 2D output formatting problem 399 2.0
okviri okviri 1.5e, Output Formatting, E use 2D array to simplify the process 447 1.9
skener skener 1.5e, Output Formatting, E enlarging 2D character array 2067 1.5
ultimatebinarywatch ultimatebinarywatch 1.5e, Output Formatting, E simple 2D output formatting problem; 4 vertical bitmasks 205 1.4
welcomesign welcomesign 1.5e, Output Formatting, E format the input into requested output 429 1.8
endurvinnsla endurvinnsla 1.5f, Easy, Involving String just count 'ekki plast' and compute the answer 136 2.2
methodicmultiplication methodicmultiplication 1.5f, Easy, Involving String reading comprehension; very easy answer 381 1.6
nop nop 1.5f, Easy, Involving String one loop; simply count and modify distances between two UPPERCASE characters 94 2.1
ptice ptice 1.5f, Easy, Involving String just a simple simulation 2100 1.5
pubrunda pubrunda 1.5f, Easy, Involving String just check as asked; linear pass 105 2.1
sevenwonders sevenwonders 1.5f, Easy, Involving String one pass 4776 1.4
spellingbee spellingbee 1.5f, Easy, Involving String trivial; just do as asked; string property checks 17 3.2
yinyangstones yinyangstones 1.5f, Easy, Involving String trick question; just check if number of whites equals to number of blacks 1365 1.8
bela bela 1.6a, Game (Card) simple card scoring problem 3731 1.3
karte karte 1.6a, Game (Card) simple 1600 1.7
memorymatch memorymatch 1.6a, Game (Card) interesting simulation game; many corner cases 161 4.0
pokerhand pokerhand 1.6a, Game (Card) frequency count; report max 2173 1.4
shuffling shuffling 1.6a, Game (Card) simulate card shuffling operation 218 2.8
bijele bijele 1.6b, Game (Chess) super simple 10381 1.4
checkmateinone checkmateinone 1.6b, Game (Chess) case analysis; only move rook once; cannot jump over own King; do not move rook to position that can be attacked by the ... 191 4.5
chess chess 1.6b, Game (Chess) bishop movements; either impossible, 0, 1, or 2 ways - one of this can be invalid; just use brute force 856 2.9
empleh empleh 1.6b, Game (Chess) the reverse problem of Kattis - helpme 245 1.8
helpme helpme 1.6b, Game (Chess) convert the given chess board into chess notation 302 2.4
hexagonalrooks hexagonalrooks 1.6b, Game (Chess) count number of two consecutive rook movements on hexagonal grid; try all possible 91 (intermediate) cells after simplif... 18 3.2
connectthedots connectthedots 1.6c, Game (Others), Easier classic children game; output formatting 213 3.6
gamerank gamerank 1.6c, Game (Others), Easier simulate the ranking update process 732 3.9
guessinggame guessinggame 1.6c, Game (Others), Easier use a 1D flag array; also available at UVa 10530 - Guessing Game 684 2.7
pvbg pvbg 1.6c, Game (Others), Easier find min plus 1 727 1.8
trik trik 1.6c, Game (Others), Easier simple simulation game 7191 1.4
battleship battleship 1.6d, Game (Others), Harder simulation; reading comprehension; many corner cases 120 5.4
matchgame matchgame 1.6d, Game (Others), Harder two cases for yes: 1 (sample 2) or 2 digits (sample 2) difference; no for 3 digits differences; be careful for cases lik... 204 4.6
rockpaperscissors rockpaperscissors 1.6d, Game (Others), Harder count wins and losses; output win average; also available at UVa 10903 - Rock-Paper-Scissors ... 820 3.7
rockscissorspaper rockscissorspaper 1.6d, Game (Others), Harder 2D arrays manipulation; also available at UVa 10443 - Rock, Scissors, Paper 153 4.8
tictactoe2 tictactoe2 1.6d, Game (Others), Harder check validity of Tic Tac Toe game; tricky; also available at UVa 10363 - Tic Tac Toe 167 5.3
turtlemaster turtlemaster 1.6d, Game (Others), Harder interesting board game to teach programming for children; simulation 323 2.9
attendance2 attendance2 1.6e, Real Life, Easier we frequently encounter this problem in real-life 220 1.9
calories calories 1.6e, Real Life, Easier are you concerned with your weights?; also available at UVa 10554 - Calories from Fat 328 2.0
chopin chopin 1.6e, Real Life, Easier you can learn a bit of music with this problem 823 1.8
compass compass 1.6e, Real Life, Easier your typical smartphone's compass function usually has this small feature 1529 2.0
cornhusker cornhusker 1.6e, Real Life, Easier do the estimation as explained 365 1.5
cprnummer cprnummer 1.6e, Real Life, Easier just do the check as described 197 1.5
elevatingtheprank elevatingtheprank 1.6e, Real Life, Easier (B-A)*4 + numbers of floors in [A+1..B-1] that are pressed 63 1.7
espresso espresso 1.6e, Real Life, Easier simple control flow 851 2.1
fbiuniversal fbiuniversal 1.6e, Real Life, Easier a bit of base number conversion; base 27 to base 10, if valid 369 2.2
fizzbuzz fizzbuzz 1.6e, Real Life, Easier actually just about easy divisibility properties 10274 1.3
fizzbuzz2 fizzbuzz2 1.6e, Real Life, Easier divisibility properties; very similar to Kattis - fizzbuzz 212 2.7
generalizedfizzbuzz generalizedfizzbuzz 1.6e, Real Life, Easier easy divisibility properties 83 1.6
heartrate heartrate 1.6e, Real Life, Easier real life problem 3205 1.3
lettasta lettasta 1.6e, Real Life, Easier just simulate as asked 230 1.4
measurement measurement 1.6e, Real Life, Easier going down: multiply; going up: divide 641 2.0
parking parking 1.6e, Real Life, Easier a possible real life application; simple loops and if-statements are enough to solve this problem 1523 1.6
trainpassengers trainpassengers 1.6e, Real Life, Easier create a verifier; be careful of corner cases 1807 2.1
transitwoes transitwoes 1.6e, Real Life, Easier a possible real life scenario; simulate as asked 353 1.3
wertyu wertyu 1.6e, Real Life, Easier use 2D mapper array to simplify the problem; also available at UVa 10082 - WERTYU 768 2.9
beatspread beatspread 1.6f, Real Life, Medium be careful with boundary cases!; also available at UVa 10812 - Beat the Spread 980 2.4
bubbletea bubbletea 1.6f, Real Life, Medium simple simulation 1694 2.6
carousel 1.6f, Real Life, Medium single loop; keep best; skip a > m 711 2.4
climbingstairs climbingstairs 1.6f, Real Life, Medium observation: go to office (k), go to registration desk (r), go up/down 1 floor until you reach n steps, go home; repetit... 210 4.1
dodecaphony dodecaphony 1.6f, Real Life, Medium music lesson; do as asked 98 3.2
fastfood fastfood 1.6f, Real Life, Medium eventually just one pass due to the constraints 1169 1.9
luhnchecksum luhnchecksum 1.6f, Real Life, Medium very similar (~95%) to UVa 11743 836 1.6
musicalscales musicalscales 1.6f, Real Life, Medium music lesson; use array(s) to help simplify the code 674 1.6
recipes recipes 1.6f, Real Life, Medium real life problem for a cook; just simulate the requirements 731 1.8
score score 1.6f, Real Life, Medium medium difficulty; do as asked; just be careful 173 3.5
streamlag streamlag 1.6f, Real Life, Medium easier if we compute the required lag in offline mode, i.e., read all the packet arrival times upfront 397 3.1
taktsvedjur taktsvedjur 1.6f, Real Life, Medium combo hits calculation is important in rhythm games 316 2.3
toilet toilet 1.6f, Real Life, Medium simulation; be careful of corner cases 1756 2.4
utf8 utf8 1.6f, Real Life, Medium parsing; prefix checks 65 2.5
wordcloud wordcloud 1.6f, Real Life, Medium just a simulation; but be careful of corner cases 322 2.4
workingfromhome workingfromhome 1.6f, Real Life, Medium contextual COVID-19 pandemic-related situation; just simulate the requirement 236 4.5
bungeejumping bungeejumping 1.6g, Real Life, Harder real life Physics simulation; need someone who is good with Physics to understand the problem and derive the required fo... 64 4.8
creditcard creditcard 1.6g, Real Life, Harder real life issue; precision error issue if we do not convert double (with just 2 digits after decimal point) into long lo... 123 6.3
demeritpoints demeritpoints 1.6g, Real Life, Harder real-life; harder; multiple corner cases 65 6.5
saxophone saxophone 1.6g, Real Life, Harder about musical instruments; also available at UVa 10415 - Eb Alto Saxophone Player 268 2.4
tenis tenis 1.6g, Real Life, Harder Tennis scoring rules; tricky test cases; be careful 78 5.0
touchscreenkeyboard touchscreenkeyboard 1.6g, Real Life, Harder follow the requirements; sort 636 1.9
workout workout 1.6g, Real Life, Harder gym simulation; use 1D arrays to help you simulate the time quickly 151 5.7
countingdays countingdays 1.6h, Time, Easier computing number of elapsed days via black-box functions 64 2.6
datum datum 1.6h, Time, Easier Java GregorianCalendar, DAY_OF_WEEK 3019 1.4
friday friday 1.6h, Time, Easier the answer depends on the start day of the month 1059 1.9
justaminute justaminute 1.6h, Time, Easier linear pass; total seconds/(total minutes*60) 1512 1.7
klockan2 klockan2 1.6h, Time, Easier try all 24*60 possibilities 208 1.8
marswindow marswindow 1.6h, Time, Easier simple advancing of year and month by 26 months or 2 years+2 months each; direct formula exists 830 2.0
parentgap parentgap 1.6h, Time, Easier difference of two specific Sundays 336 2.3
savingdaylight savingdaylight 1.6h, Time, Easier convert hh:mm to minute; compute difference of ending and starting; then convert minute to hh:mm again 986 2.1
secondopinion secondopinion 1.6h, Time, Easier convert seconds to hours : minutes : seconds 823 1.5
spavanac spavanac 1.6h, Time, Easier convert hh:mm to minute, reduce by 45 minutes, then convert minute to hh:mm again 8877 1.4
bestbefore bestbefore 1.6i, Time, Harder tedious; 3! = 6 possibilities to check 148 4.0
birthdayboy birthdayboy 1.6i, Time, Harder convert mm-dd into [0..364]; use DAT; find largest gap via brute force 108 4.6
busyschedule busyschedule 1.6i, Time, Harder sort the time; be careful of corner cases 811 2.4
dst dst 1.6i, Time, Harder straightforward; modulo 611 2.1
natrij natrij 1.6i, Time, Harder convert hh:mm:ss to seconds; make sure the second time is larger than the first time; corner case: 24:00:00 1136 2.6
semafori semafori 1.6i, Time, Harder simple simulation 724 2.0
tgif tgif 1.6i, Time, Harder given the day of 1 Jan of an unspecified year, find the DAY_OF_WEEK of another day of that year; use Java GregorianCalen... 82 3.2
timezones timezones 1.6i, Time, Harder follow the description, tedious; also available at UVa 10371 - Time Zones 67 5.3
convertingromans convertingromans 1.6j, Roman Numerals important: "subtract any digit written to the left of a larger digit, even if they are not directly adjacent" 274 2.9
rimski rimski 1.6j, Roman Numerals to Roman/to Decimal conversion problem; use next permutation to be sure 118 4.5
romanholidays romanholidays 1.6j, Roman Numerals generate and sort the first 1K Roman strings; ''M'' is at index 945; append prefix 'M' for numbers larger than 1K 92 3.6
asciiaddition asciiaddition 1.6k, Time Waster, Easier a+b problem in text format 509 1.9
averagespeed averagespeed 1.6k, Time Waster, Easier distance = speed*time elapsed; also available at UVa 10281 - Average Speed 322 3.7
bluetooth bluetooth 1.6k, Time Waster, Easier input parsing; check many subcases 318 1.9
gerrymandering gerrymandering 1.6k, Time Waster, Easier just a reading comprehension problem; do as asked 1187 1.4
glitchbot glitchbot 1.6k, Time Waster, Easier O(n^2) simulation; only output one answer 1036 2.0
hnappasetningaskipti hnappasetningaskipti 1.6k, Time Waster, Easier peruse the given table.tsv to avoid silly typos 151 2.0
pachydermpeanutpacking pachydermpeanutpacking 1.6k, Time Waster, Easier time waster; simple one loop simulation 322 1.9
printingcosts printingcosts 1.6k, Time Waster, Easier clear time waster; the hard part is in parsing the costs of each character in the problem description 705 2.2
froggie froggie 1.6l, Time Waster, Harder just a simulation; but many corner cases; S can be 0 296 6.8
functionalfun functionalfun 1.6l, Time Waster, Harder just follow the description; 5 cases; tedious parsing problem; requires a kind of mapper 487 1.9
interpreter interpreter 1.6l, Time Waster, Harder need careful implementation; just follow the instruction 224 3.7
lumbercraft lumbercraft 1.6l, Time Waster, Harder time waster; 2D grid simulation 69 5.0
sabor sabor 1.6l, Time Waster, Harder ad hoc; hard simulation; analyze that the simulation terminates 53 5.2
touchdown touchdown 1.6l, Time Waster, Harder time waster; reading comprehension; several corner cases 114 3.6
windows windows 1.6l, Time Waster, Harder LA 7162 - WorldFinals Marrakech15; tedious simulation problem; also available at UVa 01721 - Window Manager 92 7.6

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