Problems

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Total results21,331 problems

Kids love candyEasy2
Math, GreedyNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Contest Venue SetupEasy2
Matrix, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Combination LockEasy2
Brute force, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
VicinityEasy2
Brute force, GeometryNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Stone Game 5Easy2
Game theory, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Show Me The OperatorsEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Anti-Arithmetic PermutationEasy2
Brute force, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Fibonacci remainderEasy2
Math, SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Qurban 2011Easy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
BeeEasy2
Implementation, Array +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Extending Goldbach's ConjectureEasy2
MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Word SearchingEasy2
String matching, StringNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Jane's First WordsEasy2
String matching, StringNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Easy EncryptionEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Length and Frequency of SentencesEasy2
String, Hash map +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Form GuideEasy2
Implementation, StringNo attempts yetTime limit1sMemory limit128 MB
Judgeable
The KingEasy2
Greedy, MathNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Rectangle intersectionEasy2
Geometry, IntervalsNo attempts yetTime limit2sMemory limit512 MB
Judgeable
CipherEasy2
Brute force, StringNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Cuckoo for HashingEasy2
Simulation, Hash map +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
UndercutEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
EuclidEasy2
Number theoryNo attempts yetTime limit2sMemory limit512 MB
Judgeable
LampEasy2
Simulation, ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Cellular AutomataEasy2
Brute force, SimulationNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
Maximum FrequencyEasy2
Hash map, ArrayNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
CarsEasy2
Simulation, ImplementationNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
Zeros in a FactorialEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
RouteEasy2
Array, ImplementationNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
The Euclidean AlgorithmEasy2
Simulation, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Mingyun's PasswordEasy2
String, Brute forceNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Centroid of Point MassesEasy2
Math, ImplementationNo attempts yetTime limit3sMemory limit128 MB
Judgeable
Word PuzzleEasy2
Hash map, StringNo attempts yetTime limit3sMemory limit256 MB
Judgeable
Have you had your birthday yet?Easy2
ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Cedric's cypherEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
The Hardest Problem EverEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Polar ExplorerEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
HMs and TMsEasy2
Implementation, Brute forceNo attempts yetTime limit1sMemory limit128 MB
Judgeable
VoteEasy2
Simulation, ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Party InvitationEasy2
Simulation, ArrayNo attempts yetTime limit2sMemory limit256 MB
Judgeable
Assigning PartnersEasy2
Hash map, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Mirror TenderEasy2
IntervalsNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Microwave ButtonsEasy2
Greedy, MathNo attempts yetTime limit1sMemory limit64 MB
Judgeable
Finding NemoEasy2
StringNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Palindrome LinesEasy2
Two pointers, StringNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Magic SquaresEasy2
Matrix, SimulationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Focal Length of a LensEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Clean UpEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Word SwapEasy2
Implementation, StringNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Aligned CalendarEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Odysseus and the SirensEasy2
Implementation, String +1No attempts yetTime limit1sMemory limit256 MB
Judgeable
Milo of Croton and the CalfEasy2
SimulationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Tax Rate ChangedEasy2
Brute force, MathNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Toroidal gridEasy2
Implementation, GraphNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Dice GameEasy2
Probability, Brute forceNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Train PassengersEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Runway PlanningEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Ice Bucket ChallengeEasy2
MathNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Amino AcidEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit64 MB
Judgeable
HeadshotEasy2
Probability, StringNo attempts yetTime limit1sMemory limit64 MB
Judgeable
Radix 32 ConversionEasy2
Math, StringNo attempts yetTime limit1sMemory limit64 MB
Judgeable
Van Gogh's Work ScheduleEasy2
Simulation, QueueNo attempts yetTime limit1sMemory limit64 MB
Judgeable
Growling GearsEasy2
MathNo attempts yetTime limit1sMemory limit256 MB
Judgeable
MiscalculationEasy2
SimulationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
TriplesEasy2
Brute force, MathNo attempts yetTime limit5sMemory limit256 MB
Judgeable
Turtle GraphicsEasy2
Simulation, ArrayNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Alarm ClockEasy2
Brute force, ImplementationNo attempts yetTime limit2sMemory limit256 MB
Judgeable
Joy of FlightEasy2
Implementation, Simulation +1No attempts yetTime limit2sMemory limit256 MB
Judgeable
Pangram CheckerEasy2
String, Hash mapNo attempts yetTime limit3sMemory limit256 MB
Judgeable
The return of the KingEasy2
String, GreedyNo attempts yetTime limit1sMemory limit256 MB
Judgeable
EligibilityEasy2
ImplementationNo attempts yetTime limit2sMemory limit256 MB
Judgeable
Professor Tardiness MaxEasy2
MathNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Anniversary 1Easy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Anniversary 2Easy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
TorusEasy2
ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Queens on Bad TermsEasy2
Implementation, MatrixNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Hitting the TargetsEasy2
Geometry, ImplementationNo attempts yetTime limit2sMemory limit256 MB
Judgeable
The Wet KeypadEasy2
Implementation, SimulationNo attempts yetTime limit1sMemory limit32 MB
Judgeable
Most Chosen NumberEasy2
Array, ImplementationNo attempts yetTime limit5sMemory limit256 MB
Judgeable
FilterEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Closest Web Color NameEasy2
Brute force, MathNo attempts yetTime limit2sMemory limit256 MB
Judgeable
Working HoursEasy2
Implementation, String +1No attempts yetTime limit2sMemory limit256 MB
Judgeable
Urdu orthography verificationEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Mushrooms on Half a PizzaEasy2
Brute force, ArrayNo attempts yetTime limit1sMemory limit32 MB
Judgeable
Crossword Clue NumberingEasy2
Implementation, MatrixNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Cow RoutingEasy2
Implementation, ArrayNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Date in SeoulEasy2
ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Paprika ID CardsEasy2
Simulation, ArrayNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Weather ForecasterEasy2
Simulation, ArrayNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Canteen CheckoutEasy2
Brute force, MathNo attempts yetTime limit1sMemory limit64 MB
Judgeable
RövarspråketEasy2
Implementation, StringNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Wait TimeEasy2
Simulation, Hash mapNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Reversing basketsEasy2
Array, SimulationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Rotating the basket orderEasy2
Simulation, ArrayNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Comma Separated SumEasy2
String, MathNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Four NumbersEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit256 MB
Judgeable
BeltsEasy2
Simulation, MathNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Counting FriendsEasy2
Graph, ArrayNo attempts yetTime limit1sMemory limit256 MB
Judgeable
International MeetingEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Divide the land into trianglesEasy2
SortingNo attempts yetTime limit1sMemory limit16 MB
Judgeable
Veni, vidi, viciEasy2
String, MathNo attempts yetTime limit1sMemory limit256 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Kids love candyEach test case gives candy piles and K, and asks for the most children who can each receive at least K pieces of a single kind.	Easy2	MathGreedy	No attempts yet	1s	128 MB	Judgeable
Contest Venue SetupCount the schools that have two of their teams seated in king-adjacent cells of an N by M grid with empty seats.	Easy2	MatrixImplementation	No attempts yet	1s	128 MB	Judgeable
Combination LockCount distinct triples of dial positions within circular distance 2 of either of two given combinations.	Easy2	Brute forceMath	No attempts yet	1s	128 MB	Judgeable
VicinityFor each query, count how many of the n points lie within distance d_v of the chosen base point, excluding the base point itself.	Easy2	Brute forceGeometry	No attempts yet	1s	128 MB	Judgeable
Stone Game 5Two players alternately take 1 or 3 stones from a pile of N, and the program prints SK or CY for optimal play.	Easy2	Game theoryMath	No attempts yet	1s	128 MB	Judgeable
Show Me The OperatorsEvaluate each space-separated expression in two left-to-right sweeps and print the operators in execution order with the final value.	Easy2	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Anti-Arithmetic PermutationFor each permutation of 0 to n-1, decide whether any three terms in order form an arithmetic progression.	Easy2	Brute forceMath	No attempts yet	1s	128 MB	Judgeable
Fibonacci remainderFor each test case, compute the P-th Fibonacci number of the sequence starting 1, 1 modulo Q and print it as Case #x: M.	Easy2	MathSimulation	No attempts yet	1s	128 MB	Judgeable
Qurban 2011Given buffalo part orders and sheep orders, round buffalo parts up by seven and pack the animals into trips of three buffaloes or six sheep.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
BeeThe program counts logged jobs under each of seven bee work codes and prints each count with its share of the total.	Easy2	ImplementationArray+1	No attempts yet	1s	128 MB	Judgeable
Extending Goldbach's ConjectureThe program reads each m and prints whether m consecutive odd integers sum to m cubed and the first one when they do.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
Word SearchingCount case-sensitive overlapping occurrences of a given word, each fully inside one line of the following text.	Easy2	String matchingString	No attempts yet	1s	128 MB	Judgeable
Jane's First WordsCheck each input word against the pattern da+dd?(i\|y) and print whether Jane called for daddy or is cooing.	Easy2	String matchingString	No attempts yet	1s	128 MB	Judgeable
Easy EncryptionEach letter becomes its two-digit code and each digit gains a # prefix while other characters stay unchanged.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Length and Frequency of SentencesCount the words in each of N sentences and report how often each length occurs in ascending order.	Easy2	StringHash map+1	No attempts yet	1s	128 MB	Judgeable
Form GuideParse home and away scorelines into win, draw, and loss marks, print the overall, home, and away form strings, and report the longest run of each mark.	Easy2	ImplementationString	No attempts yet	1s	128 MB	Judgeable
The KingPick any subset of up to 100 values from minus 3 to 3 so the sum of the chosen values raised to the given power 1 to 3 is as large as possible.	Easy2	GreedyMath	No attempts yet	2s	128 MB	Judgeable
Rectangle intersectionCompute the area shared by all n axis-aligned rectangles, or 0 when they do not all overlap.	Easy2	GeometryIntervals	No attempts yet	2s	512 MB	Judgeable
CipherDecrypt a Caesar-shifted message by trying all 26 shifts and picking the one where both CHIPMUNKS and LIVE appear.	Easy2	Brute forceString	No attempts yet	2s	512 MB	Judgeable
Cuckoo for HashingSimulate cuckoo hashing insertions into two mod-indexed tables with displacement and print the final table contents.	Easy2	SimulationHash map+1	No attempts yet	2s	128 MB	Judgeable
UndercutAdd up both players' scores across card rounds where the higher card scores unless the lower card is exactly one less.	Easy2	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
EuclidRead two positive integers up to 32767 and print their greatest common divisor.	Easy2	Number theory	No attempts yet	2s	512 MB	Judgeable
LampGuards patrol in roster order, each toggling the lamps in one arithmetic progression, and you report how many lamps stay on.	Easy2	SimulationArray	No attempts yet	1s	128 MB	Judgeable
Cellular AutomataSimulate all 64 update rules for g generations on the n by n grid and print the smallest rule that turns the start state into the end state.	Easy2	Brute forceSimulation	No attempts yet	2s	1024 MB	Judgeable
Maximum FrequencyGiven N integers, count how many times each value appears and print the largest count.	Easy2	Hash mapArray	No attempts yet	2s	1024 MB	Judgeable
CarsSimulate n cars adjusting speed by 5 m/s every 5 seconds to keep gaps within 80 to 100 meters, and output -1 on collision or the front car distance.	Easy2	SimulationImplementation	No attempts yet	2s	1024 MB	Judgeable
Zeros in a FactorialCount how many zero digits appear in the decimal representation of n factorial for a given n below 100.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
RouteCount the maximal runs of level, uphill, and downhill metre sections along the looped jogging route starting at pole 1.	Easy2	ArrayImplementation	No attempts yet	2s	1024 MB	Judgeable
The Euclidean AlgorithmCount how many subtraction steps the original Euclidean algorithm needs to find the gcd of two integers up to 32767.	Easy2	SimulationMath	No attempts yet	1s	128 MB	Judgeable
Mingyun's PasswordFind the word whose reverse also appears in the list and print its length and middle letter.	Easy2	StringBrute force	No attempts yet	1s	128 MB	Judgeable
Centroid of Point MassesCompute the mass-weighted average x and y over each point set and print each centroid rounded to two decimals.	Easy2	MathImplementation	No attempts yet	3s	128 MB	Judgeable
Word PuzzleDecide for each pair of strings whether the gathered letters can be rearranged to form the original word.	Easy2	Hash mapString	No attempts yet	3s	256 MB	Judgeable
Have you had your birthday yet?For each birth date, tell whether its 2007 birthday already passed relative to 4 August, with special outputs for 4 August and 29 February.	Easy2	Implementation	No attempts yet	1s	128 MB	Judgeable
Cedric's cypherDecrypt each Caesar-ciphered line using the trailing encrypted A to recover the shift and drop that marker.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
The Hardest Problem EverDecode each START/END block by shifting every uppercase letter five places back and leaving other characters unchanged.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Polar ExplorerGiven planet radius, fuel, and the angle to the crash site, decide if the round trip on the shorter arc fits and report leftover fuel or reachable miles.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
HMs and TMsFind all of the first 151 Pokémon that can learn every HM or TM move on the given list and print their numbers in order.	Easy2	ImplementationBrute force	No attempts yet	1s	128 MB	Judgeable
VoteEach judge votes for the most interesting game they can afford, and the game with the most votes wins.	Easy2	SimulationArray	No attempts yet	1s	128 MB	Judgeable
Party InvitationSimulate m rounds of removing every person at a multiple of ri from the ordered list and print the survivors in order.	Easy2	SimulationArray	No attempts yet	2s	256 MB	Judgeable
Assigning PartnersYou check that every positional pairing is mutual and no student is paired with themselves.	Easy2	Hash mapImplementation	No attempts yet	1s	256 MB	Judgeable
Mirror TenderDecide for each test case whether one workshop's width and height ranges contain every other workshop's ranges.	Easy2	Intervals	No attempts yet	1s	256 MB	Judgeable
Microwave ButtonsPress the 5-minute, 1-minute, and 10-second buttons to total exactly T seconds with the fewest presses, or print -1 when impossible.	Easy2	GreedyMath	No attempts yet	1s	64 MB	Judgeable
Finding NemoPrint Found for each input line before EOI when the letters n, e, m, o appear in order ignoring case, else Missing.	Easy2	String	No attempts yet	1s	256 MB	Judgeable
Palindrome LinesDecide for each of n short lines whether it reads the same forward and backward, ignoring letter case.	Easy2	Two pointersString	No attempts yet	1s	256 MB	Judgeable
Magic SquaresCheck each test case square by comparing every row, column, and both diagonal sums and report whether it is magic.	Easy2	MatrixSimulation	No attempts yet	1s	256 MB	Judgeable
Focal Length of a LensGiven object and image distances for each test case, compute the lens focal length and print it rounded to one decimal place.	Easy2	MathImplementation	No attempts yet	1s	256 MB	Judgeable
Clean UpRecompute each of the nine batting averages after adding the new series and reorder the lineup around the new best average.	Easy2	SimulationImplementation	No attempts yet	1s	256 MB	Judgeable
Word SwapSum the per-position letter differences between each pair of equal-length words and report the coins earned, paid, or free.	Easy2	ImplementationString	No attempts yet	1s	256 MB	Judgeable
Aligned CalendarConvert each Gregorian date into the 13-month calendar with 28-day months and report the leftover days as holidays.	Easy2	MathImplementation	No attempts yet	1s	256 MB	Judgeable
Odysseus and the SirensThe program scores every melody under each candidate key by summing note penalties and prints the numbered key with the smallest total.	Easy2	ImplementationString+1	No attempts yet	1s	256 MB	Judgeable
Milo of Croton and the CalfSimulate Milo lifting the calf as it gains a pound a day, with strength gains after 3 days and soreness lasting 2 days, and report the first failure day.	Easy2	Simulation	No attempts yet	1s	256 MB	Judgeable
Tax Rate ChangedFind the pair of pre-tax prices that summed to s after x% tax and gives the largest total after y% tax.	Easy2	Brute forceMath	No attempts yet	1s	256 MB	Judgeable
Toroidal gridPrint the given snake sweep of columns 0 to n-2 plus the climb up column n-1 to list a Hamiltonian cycle of the m by n toroidal grid.	Easy2	ImplementationGraph	No attempts yet	1s	256 MB	Judgeable
Dice GameEach player rolls two dice with consecutive face ranges and the larger total wins, so compute both win probabilities from the four ranges.	Easy2	ProbabilityBrute force	No attempts yet	1s	256 MB	Judgeable
Train PassengersDecide if per-station counts of passengers leaving, boarding, and left waiting fit the train capacity and boarding rules.	Easy2	SimulationImplementation	No attempts yet	1s	256 MB	Judgeable
Runway PlanningGiven each heading in degrees, compute the two-digit runway number by rounding and folding to the range 1 to 18.	Easy2	MathImplementation	No attempts yet	1s	256 MB	Judgeable
Ice Bucket ChallengeFind the fewest ice-pouring participants needed to reach a donation goal when each pourer donates 10 and recruits K friends while skippers donate 100.	Easy2	Math	No attempts yet	1s	256 MB	Judgeable
Amino AcidParse each formula into element counts and print the molecular weight, or Invalid formula for other elements.	Easy2	StringImplementation	No attempts yet	1s	64 MB	Judgeable
HeadshotAfter a click on a circular cylinder, compare firing at once against spinning first and print which choice is safer.	Easy2	ProbabilityString	No attempts yet	1s	64 MB	Judgeable
Radix 32 ConversionConvert each base-32 string of up to 8 digits to its decimal value and to binary by expanding every digit to 5 bits.	Easy2	MathString	No attempts yet	1s	64 MB	Judgeable
Van Gogh's Work ScheduleSimulate a first-come queue of painting jobs and print arrivals, starts, and finishes for hours 0 to 23.	Easy2	SimulationQueue	No attempts yet	1s	64 MB	Judgeable
Growling GearsFor each gear compute the vertex value of -aR^2 + bR + c and output the gear with the largest maximum.	Easy2	Math	No attempts yet	1s	256 MB	Judgeable
MiscalculationGiven a digit expression with + and * and Bob's answer, report whether it matches the precedence evaluation, the left-to-right evaluation, both, or neither.	Easy2	Simulation	No attempts yet	1s	256 MB	Judgeable
TriplesCount triples x<=y<=z<=m with x^j+y^j=z^j for each exponent j from 2 to n and print the total.	Easy2	Brute forceMath	No attempts yet	5s	256 MB	Judgeable
Turtle GraphicsSimulate a turtle that steps forward and turns on a 64 by 64 grid, then report its final cell and how many cells it visited more than once.	Easy2	SimulationArray	No attempts yet	1s	256 MB	Judgeable
Alarm ClockPrint the earliest hh:mm time whose four digits use exactly n lit segments, or Impossible when no such time exists.	Easy2	Brute forceImplementation	No attempts yet	2s	256 MB	Judgeable
Joy of FlightAdd up the wind drift over k seconds and, if the remaining distance fits the speed limit, print the evenly paced flight positions.	Easy2	ImplementationSimulation+1	No attempts yet	2s	256 MB	Judgeable
Pangram CheckerCount how many times each English letter appears in every sentence and print its pangram grade.	Easy2	StringHash map	No attempts yet	3s	256 MB	Judgeable
The return of the KingSplit the digit string into grades of 1 to 10 in the single valid way and print the average rounded to two decimals.	Easy2	StringGreedy	No attempts yet	1s	256 MB	Judgeable
EligibilityDecide each student contest status from study start year, birth year, and completed courses under four ordered rules.	Easy2	Implementation	No attempts yet	2s	256 MB	Judgeable
Professor Tardiness MaxFind the largest integer t with t plus t squared at most d for each given class length.	Easy2	Math	No attempts yet	1s	256 MB	Judgeable
Anniversary 1Starting from April 2, 2014 as day 1, add N-1 days with leap years and print the date as YYYY-MM-DD.	Easy2	SimulationImplementation	No attempts yet	1s	256 MB	Judgeable
Anniversary 2Given a start date as day 1 and a number N, print the date N minus 1 days later following the given leap year rules.	Easy2	SimulationImplementation	No attempts yet	1s	256 MB	Judgeable
TorusPrint 1 for each test case followed by the prescribed vertex order that visits every vertex of the toroidal lattice exactly once.	Easy2	Implementation	No attempts yet	1s	256 MB	Judgeable
Queens on Bad TermsCheck an 8x8 board holding eight queens and print valid only when no two queens share a row, column, or diagonal.	Easy2	ImplementationMatrix	No attempts yet	1s	256 MB	Judgeable
Hitting the TargetsCount, for each of up to 100 shot points, how many of up to 30 given rectangles and circles contain it, boundaries included.	Easy2	GeometryImplementation	No attempts yet	2s	256 MB	Judgeable
The Wet KeypadGiven a permuted phone keypad, encode a message of up to 100 letters into multi-tap presses with # separators.	Easy2	ImplementationSimulation	No attempts yet	1s	32 MB	Judgeable
Most Chosen NumberPick the number that appears most often in each test case, breaking ties by the smaller number.	Easy2	ArrayImplementation	No attempts yet	5s	256 MB	Judgeable
FilterThe program checks each Bloom filter against every queried user id and lists the files that may hold at least one of them.	Easy2	SimulationImplementation	No attempts yet	1s	256 MB	Judgeable
Closest Web Color NameThe program maps each RGB triple to the closest of 16 named HTML colors by Euclidean distance, breaking ties by table order.	Easy2	Brute forceMath	No attempts yet	2s	256 MB	Judgeable
Working HoursAdd signed hour and minute terms in a flexible format and print each total as H:MM.	Easy2	ImplementationString+1	No attempts yet	2s	256 MB	Judgeable
Urdu orthography verificationCheck whether each encoded Urdu letter uses the detached, initial, medial or final shape required by its position and the two special vowels.	Easy2	SimulationImplementation	No attempts yet	1s	256 MB	Judgeable
Mushrooms on Half a PizzaGiven mushroom counts on eight circular pizza slices, find the largest total on any four consecutive slices.	Easy2	Brute forceArray	No attempts yet	1s	32 MB	Judgeable
Crossword Clue NumberingScan the grid for empty cells that begin a word of at least three cells across or down and print them in reading order.	Easy2	ImplementationMatrix	No attempts yet	1s	256 MB	Judgeable
Cow RoutingFind the cheapest single flight route on which city A appears before city B, or report -1 when none exists.	Easy2	ImplementationArray	No attempts yet	1s	256 MB	Judgeable
Date in SeoulAdd nine hours to the given UTC date output and print the resulting Seoul calendar date as YYYY-MM-DD.	Easy2	Implementation	No attempts yet	1s	256 MB	Judgeable
Paprika ID CardsSimulate one left-to-right pass of conditional card swaps, then count paprikas whose final card matches their goal.	Easy2	SimulationArray	No attempts yet	1s	256 MB	Judgeable
Weather ForecasterClouds drift east one cell per minute, and each cell reports how many minutes until a cloud first arrives, or -1 if none ever does.	Easy2	SimulationArray	No attempts yet	1s	256 MB	Judgeable
Canteen CheckoutChoose the number of fixed-price 4-item set menus that minimizes the total bill for the tray.	Easy2	Brute forceMath	No attempts yet	1s	64 MB	Judgeable
RövarspråketTranslate one lowercase word by expanding each consonant into three letters under the given vowel and consonant rules.	Easy2	ImplementationString	No attempts yet	1s	256 MB	Judgeable
Wait TimeReconstruct message timestamps from the log and sum each friend reply wait time, reporting -1 for a friend with an unanswered message.	Easy2	SimulationHash map	No attempts yet	1s	256 MB	Judgeable
Reversing basketsApply M given interval reversals in order to baskets numbered 1 to N, then print the final order from the left.	Easy2	ArraySimulation	No attempts yet	1s	256 MB	Judgeable
Rotating the basket orderPerform M given segment rotations on baskets numbered 1 to N and print the final left-to-right order.	Easy2	SimulationArray	No attempts yet	1s	256 MB	Judgeable
Comma Separated SumAdd all the natural numbers listed in the comma-separated string S.	Easy2	StringMath	No attempts yet	1s	256 MB	Judgeable
Four NumbersAdd the two numbers formed by writing B directly after A and D directly after C.	Easy2	ImplementationMath	No attempts yet	1s	256 MB	Judgeable
BeltsGiven each belt rotation ratio and twist, compute the last wheel speed and direction when the first wheel turns clockwise once per minute.	Easy2	SimulationMath	No attempts yet	1s	256 MB	Judgeable
Counting FriendsCount the friends of each of N students from M mutual friendship pairs and print the N totals.	Easy2	GraphArray	No attempts yet	1s	256 MB	Judgeable
International MeetingConvert a HH:MM meeting time from one UTC offset to N coworker offsets and print each local time of day.	Easy2	MathImplementation	No attempts yet	1s	256 MB	Judgeable
Divide the land into trianglesSort all pegs by x then y, split the order into consecutive triples, and print each triple's input numbers in increasing order.	Easy2	Sorting	No attempts yet	1s	16 MB	Judgeable
Veni, vidi, viciDrop the last letter of each odd-length ciphertext, then decode every letter pair into one plain letter with the given key.	Easy2	StringMath	No attempts yet	1s	256 MB	Judgeable