Problems

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Total results21,289 problems

The PaintingEasy2
Array, Matrix +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Ways to Make RectanglesEasy2
Math, Brute force +1No attempts yetTime limit1sMemory limit256 MB
Judgeable
A Cat on a KeyboardEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
PolynomialEasy2
Math, Implementation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
KamilEasy2
Math, Combinatorics +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
JulkaEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Ant NamesEasy2
String, Implementation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Units Digit of a Power of TwoEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Rhyming VersesEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
ParkEasy2
Prefix sum, ArrayNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Bagels on a StickEasy2
ArrayNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Hidden NumberEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Caesar CipherEasy2
String, Array +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
WarehouseEasy2
Array, SimulationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Non-DivisorsEasy2
Number theory, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Sums and DifferencesEasy2
Math, CombinatoricsNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Step on the FootEasy2
MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
KwadratEasy2
Geometry, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Dividing the Chocolate BarEasy2
MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Overlapping Rectangle AreaEasy2
GeometryNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Little SnowmanEasy2
Math, Brute forceNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Bouncing BallEasy2
MathNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Ranking ManipulationEasy2
Array, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Making Grid PaperEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
ThumbtacksEasy2
ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
ChessEasy2
Greedy, ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
PaintsEasy2
MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Pear Trees and Apple TreesEasy2
ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
TournamentEasy2
MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Missing DigitsEasy2
Brute force, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Closing the CircuitEasy2
Implementation, Sorting +1No attempts yetTime limit3sMemory limit128 MB
Judgeable
MondaysEasy2
MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
KaraokeEasy2
Sliding window, StringNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Palindrome ColoringEasy2
String, Two pointersNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Rock Paper ScissorsEasy2
Probability, Math +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Shoe FactoryEasy2
Prefix sum, Brute forceNo attempts yetTime limit1sMemory limit128 MB
Judgeable
BookmakersEasy2
MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Power StripsEasy2
MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Changing a Light BulbEasy2
MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Rock Paper ScissorsEasy2
SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
TurtleEasy2
SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
SalesEasy2
Brute force, ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Molar MassEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Careless AdditionEasy2
Implementation, StringNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Heeju's Math ExamEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Guess the SongEasy2
Simulation, Hash mapNo attempts yetTime limit1sMemory limit128 MB
Judgeable
DisplayEasy2
Array, SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
TrainEasy2
Simulation, ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Olympic Country RankingEasy2
Sorting, ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Old BillEasy2
Brute force, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
ClockEasy2
Math, Sorting +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
DisplayEasy2
Greedy, SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
DecryptionEasy2
Array, StringNo attempts yetTime limit1sMemory limit128 MB
Judgeable
War GameEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Tidying the Banquet TablesEasy2
Brute force, MatrixNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Mathematical CuriosityEasy2
Brute force, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Addition in Different BasesEasy2
Implementation, String +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
WoodwormsEasy2
Matrix, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Air speed of a fully laden swallowEasy2
Implementation, String +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Sir Bedavere's Bogus DivisionEasy2
Brute force, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Taunt Exposure EstimationEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Consecutive Digits in a Rational NumberEasy2
Simulation, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Pig LatinEasy2
String, SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
W**h y**r mouth out with s**pEasy2
String, SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Check DigitsEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Word LadderEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Crossword Puzzle Clue NumberingEasy2
Simulation, Matrix +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
The Friend of My Enemy Is My EnemyEasy2
Graph, SortingNo attempts yetTime limit1sMemory limit128 MB
Judgeable
More DiceEasy2
Brute force, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Morse CodeEasy2
Hash map, StringNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Winning at tic-tac-toeEasy2
Brute force, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Reducing Improper FractionsEasy2
MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Painting PartyEasy2
Simulation, MatrixNo attempts yetTime limit5sMemory limit128 MB
Judgeable
Geometric InflationEasy2
Simulation, Math +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Arithmetic and Geometric SumsEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Integer FlippingEasy2
Bit manipulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Monitor DPIEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Ironclad Security AlgorithmEasy2
Hash map, ArrayNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Fast Food PrizesEasy2
Greedy, Math +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
MarathonerEasy2
Implementation, Hash mapNo attempts yetTime limit2sMemory limit64 MB
Judgeable
Sequence Folding GameEasy2
Simulation, ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Triangle ClassificationEasy2
ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Sanggeun's travelsEasy2
GraphNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Gholam's Simple GameEasy2
Simulation, ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Arbiter LoginEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Zombie InvasionEasy2
Simulation, MathNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Arrangement of ContestEasy2
Greedy, String +1No attempts yetTime limit2sMemory limit256 MB
Judgeable
BoxesEasy2
Simulation, MatrixNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Von NeumannEasy2
MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
The n Days of ChristmasEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Perfect ShuffleEasy2
Simulation, ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Long is a train, a train is fast, fast is a planeEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Text RollEasy2
SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Perfect Number CheckEasy2
Number theory, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
I Love CroatiaEasy2
SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Roman Catholic MassEasy2
Brute force, Matrix +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Arithmetic with MorseEasy2
Implementation, SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Presidential ElectionEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Kids love candyEasy2
Math, GreedyNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Contest Venue SetupEasy2
Matrix, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
The PaintingRead an n by m grid of . and # characters and print it rotated 90 degrees clockwise, producing m rows of n characters.	Easy2	ArrayMatrix+1	No attempts yet	1s	128 MB	Judgeable
Ways to Make RectanglesCount the number of unordered pairs (a, b) with a <= b and a*b <= n.	Easy2	MathBrute force+1	No attempts yet	1s	256 MB	Judgeable
A Cat on a KeyboardGiven a text, replace each character with the keyboard row number (1 to 5) where its key sits.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
PolynomialGiven a polynomial's coefficients and an integer x, print the last three digits of \|W(x)\|, padded with leading zeros.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
KamilGiven a word Kamil spoke, count the words he could have meant, since each position may map to one of several letters.	Easy2	MathCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
JulkaGiven the total apples and how many more Klaudia has, compute each girl's count.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Ant NamesGiven up to 100 lowercase names, print the maximum number of distinct letters found in any single name.	Easy2	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
Units Digit of a Power of TwoThe task is to print the units digit of 2 to the power n for a huge n.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Rhyming VersesCount pairs of lines with the same number of vowels and identical last k letters ignoring spaces.	Easy2	StringImplementation	No attempts yet	1s	512 MB	Judgeable
ParkFor each of up to one million heights in order, output the maximum height to its west and to its east, using its own height when no higher point exists.	Easy2	Prefix sumArray	No attempts yet	1s	512 MB	Judgeable
Bagels on a StickSlide a chosen bagel off one end of the stick after removing the fewest bagels it cannot slide through.	Easy2	Array	No attempts yet	1s	512 MB	Judgeable
Hidden NumberSum every maximal run of digits in a word of letters and digits, ignoring leading zeros.	Easy2	StringImplementation	No attempts yet	1s	256 MB	Judgeable
Caesar CipherDecode a Caesar-shifted uppercase message by matching its most frequent letter to the given original letter.	Easy2	StringArray+1	No attempts yet	1s	512 MB	Judgeable
WarehouseTally up to a million signed per-product shipment records and print the remaining stock of each product in alphabetical order.	Easy2	ArraySimulation	No attempts yet	1s	512 MB	Judgeable
Non-DivisorsGiven n, print the smallest and the largest integers from 1 to n that do not divide n.	Easy2	Number theoryMath	No attempts yet	1s	128 MB	Judgeable
Sums and DifferencesCount ordered pairs from distinct positions where the difference exceeds the sum, which holds exactly when the second element is negative.	Easy2	MathCombinatorics	No attempts yet	1s	128 MB	Judgeable
Step on the FootKozik and Adrian alternately shorten the gap by their foot lengths, and the first player facing a gap shorter than his foot wins.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
KwadratDecide whether four given points are the vertices of a non-degenerate square with sides parallel to the axes.	Easy2	GeometryImplementation	No attempts yet	1s	128 MB	Judgeable
Dividing the Chocolate BarTwo brothers split an a by b chocolate bar with one straight cut so the two pieces differ in area as little as possible.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
Overlapping Rectangle AreaGiven two axis-aligned rectangles, compute the area of their overlapping region.	Easy2	Geometry	No attempts yet	1s	128 MB	Judgeable
Little SnowmanChoose whether the fixed ball k is the bottom, middle, or top of a three-ball snowman with halved volumes to maximize total volume within x liters.	Easy2	MathBrute force	No attempts yet	1s	128 MB	Judgeable
Bouncing BallGiven drop height x and target w, find the smallest number of doublings that make x reach at least w.	Easy2	Math	No attempts yet	1s	512 MB	Judgeable
Ranking ManipulationChoose weights on the tasks you solved so you finish first, then count the contestants tied with you.	Easy2	ArrayImplementation	No attempts yet	1s	128 MB	Judgeable
Making Grid PaperPick the sheet that yields the most grid cells under the margin and spacing rules, breaking ties by area, and output its area.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
ThumbtacksFind the smallest jump that crosses the bridge using only planks without thumbtacks.	Easy2	Array	No attempts yet	1s	128 MB	Judgeable
ChessEach row holds at most one rook, so take the largest value in every row with a positive maximum and add them.	Easy2	GreedyArray	No attempts yet	1s	128 MB	Judgeable
PaintsCompute the extra red, yellow, and blue paint to buy after splitting each mixed room amount evenly between its two base colors.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
Pear Trees and Apple TreesFind the largest distance between any pear tree and any apple tree in a row of n trees.	Easy2	Array	No attempts yet	1s	128 MB	Judgeable
TournamentFor each test case with n contestants and group size k, count how many contestants can reach the final survivors under some grouping.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
Missing DigitsEach cipher hides one digit as x in A or B, and you try digits 0 to 9 to find the smallest that makes A divisible by B.	Easy2	Brute forceMath	No attempts yet	1s	128 MB	Judgeable
Closing the CircuitShift every given upper pair forward by one position modulo n and print the sorted lower pairs after TAK.	Easy2	ImplementationSorting+1	No attempts yet	3s	128 MB	Judgeable
MondaysGiven year length N, week length M, and starting weekday L, count the days from 1 to N that fall on the first weekday.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
KaraokeCount the starting positions where the next K characters of the song string are all vowels.	Easy2	Sliding windowString	No attempts yet	2s	128 MB	Judgeable
Palindrome ColoringSplit each A/B string into the fewest palindromic subsequences and output that count.	Easy2	StringTwo pointers	No attempts yet	1s	128 MB	Judgeable
Rock Paper ScissorsCompare the two players' winning chances from their move probabilities and print who is more likely to win each match.	Easy2	ProbabilityMath+1	No attempts yet	1s	128 MB	Judgeable
Shoe FactoryChoose the price p from 1 to N that maximizes the count of buyers willing to pay p times the margin p minus K.	Easy2	Prefix sumBrute force	No attempts yet	1s	128 MB	Judgeable
BookmakersDecide whether stakes on both match outcomes can guarantee a profit given decimal odds X and Y.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
Power StripsGiven N cords and strips that add K outlets each, compute how many free outlets remain after connecting everything.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
Changing a Light BulbCompute the sum 1 + 4 + ... + 4^(A-1) modulo 500000009 for the given level count A.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
Rock Paper ScissorsSimulate k rounds of rock-paper-scissors across N robots, removing round losers until one robot remains or all rounds end in a draw.	Easy2	Simulation	No attempts yet	1s	128 MB	Judgeable
TurtleSimulate the turtle's moves from the origin and report the area of the axis-aligned bounding box of its path.	Easy2	Simulation	No attempts yet	1s	128 MB	Judgeable
SalesFor each test case, count pairs of days where the earlier day sold no more than the later day and print the total.	Easy2	Brute forceArray	No attempts yet	1s	128 MB	Judgeable
Molar MassThe program parses each formula of C, H, O, and N with optional atom counts and prints its molar mass using the given weights.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Careless AdditionAdd two integers digit by digit from the right with no carries and print the column sums in order.	Easy2	ImplementationString	No attempts yet	1s	128 MB	Judgeable
Heeju's Math ExamSum the terms from position A to B in the sequence where each integer k appears k times in a row.	Easy2	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Guess the SongGiven the title words and the lyrics in order, find the earliest lyric position where at least half of the distinct title words have appeared.	Easy2	SimulationHash map	No attempts yet	1s	128 MB	Judgeable
DisplayAdd K consecutive numbers starting from the B-th value of a length-N sequence that repeats forever.	Easy2	ArraySimulation	No attempts yet	1s	128 MB	Judgeable
TrainPassengers board in order into the non-full car with the fewest same-initial riders, ties broken by load then car number, and the program prints each car count.	Easy2	SimulationArray	No attempts yet	1s	128 MB	Judgeable
Olympic Country RankingCount how many countries beat country K on gold, then silver, then bronze medals, and report its rank.	Easy2	SortingArray	No attempts yet	1s	128 MB	Judgeable
Old BillGiven N and middle digits XYZ, fill in the first and last digits of the five-digit total so N divides it, choosing the largest valid total.	Easy2	Brute forceMath	No attempts yet	1s	128 MB	Judgeable
ClockFind the time with the median clock-hand angle among five given times, breaking angle ties by earlier time.	Easy2	MathSorting+1	No attempts yet	1s	128 MB	Judgeable
DisplayFit the words of a space-separated text into the fewest rows of width w, breaking a row only when the next word does not fit.	Easy2	GreedySimulation	No attempts yet	1s	128 MB	Judgeable
DecryptionCount the letters in each sentence ignoring spaces and print the most frequent one, or ? on a tie.	Easy2	ArrayString	No attempts yet	1s	128 MB	Judgeable
War GameGiven each opponent row of archers, lancers, and riders with cyclic strengths, output the shortest row that beats every soldier in meeting order.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Tidying the Banquet TablesFour teams sit mixed across four tables, and you assign one team to each table so the fewest guests move.	Easy2	Brute forceMatrix	No attempts yet	1s	128 MB	Judgeable
Mathematical CuriosityCount pairs 0<a<b<n where a squared plus b squared plus m is divisible by a times b.	Easy2	Brute forceMath	No attempts yet	1s	128 MB	Judgeable
Addition in Different BasesAdd two numbers of up to 1000 digits in bases 1 to 35, including unary base 1, and print each equation with its sum in the same base.	Easy2	ImplementationString+1	No attempts yet	1s	128 MB	Judgeable
WoodwormsCount the table squares each woodworm ate and report the name of the one that ate the most.	Easy2	MatrixImplementation	No attempts yet	1s	128 MB	Judgeable
Air speed of a fully laden swallowYou group messy swallow flight records by subspecies and compute two average speeds for each group.	Easy2	ImplementationString+1	No attempts yet	1s	128 MB	Judgeable
Sir Bedavere's Bogus DivisionPrint every three-digit fraction with numerator in L to R that keeps its value after erasing the shared digit.	Easy2	Brute forceMath	No attempts yet	1s	128 MB	Judgeable
Taunt Exposure EstimationRead CSV time measurements and estimate total exposure with the trapezoid rule, then print the range and integral with fixed rounding.	Easy2	ImplementationMath	No attempts yet	1s	128 MB	Judgeable
Consecutive Digits in a Rational NumberReport the base-7 digits in positions f through l after the point for the fraction n over d.	Easy2	SimulationMath	No attempts yet	1s	128 MB	Judgeable
Pig LatinConvert each word to Pig Latin by moving leading consonants to the end and appending ay.	Easy2	StringSimulation	No attempts yet	1s	128 MB	Judgeable
Wh yr mouth out with s**pReplace the middle two letters of every four-letter run whose first and last letters match the given list, scanning each line left to right with no overlap.	Easy2	StringSimulation	No attempts yet	1s	128 MB	Judgeable
Check DigitsRead numbers until a # line and print each with its mod-11 weighted check digit or Rejected.	Easy2	ImplementationMath	No attempts yet	1s	128 MB	Judgeable
Word LadderDecide for each test case whether every consecutive word pair has equal length and differs in exactly one letter.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Crossword Puzzle Clue NumberingScan the letter grid, number each square that starts an across or down word, and list every entry number with its letter count.	Easy2	SimulationMatrix+1	No attempts yet	1s	128 MB	Judgeable
The Friend of My Enemy Is My EnemyPrint the direct friends of suspect s in increasing order for each network.	Easy2	GraphSorting	No attempts yet	1s	128 MB	Judgeable
More DiceGiven the sum of two six-sided dice, list every unordered pair of faces that adds up to it in sorted order.	Easy2	Brute forceImplementation	No attempts yet	1s	128 MB	Judgeable
Morse CodeDecode each test case of five space-separated Morse codes into five uppercase letters or digits.	Easy2	Hash mapString	No attempts yet	1s	128 MB	Judgeable
Winning at tic-tac-toeTry each empty cell on the 3x3 board and print the board with the smallest winning move filled.	Easy2	Brute forceImplementation	No attempts yet	1s	128 MB	Judgeable
Reducing Improper FractionsRewrite each given fraction as a mixed number, omitting the zero integer or fractional part.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
Painting PartyPaint up to 100 filled or one-pixel-border rectangles in order on an N by N grid and print the final colors.	Easy2	SimulationMatrix	No attempts yet	5s	128 MB	Judgeable
Geometric InflationSimulate the monthly price recurrence with half-up cent rounding and print the Nth month cost with comma grouping.	Easy2	SimulationMath+1	No attempts yet	1s	128 MB	Judgeable
Arithmetic and Geometric SumsGiven N and the first three terms of an arithmetic or geometric series, detect the type and output the sum of the first N terms for each data set.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Integer FlippingReverse the order of the 32 bits of each given unsigned integer and print the resulting value, stopping at -1.	Easy2	Bit manipulation	No attempts yet	1s	128 MB	Judgeable
Monitor DPICompute horizontal and vertical DPI from diagonal size and resolution with the 16:9 ratio for each line until 0 0 0.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Ironclad Security AlgorithmYou invert the word permutation defined by the two public keys and apply it to the ciphertext to recover the plaintext.	Easy2	Hash mapArray	No attempts yet	1s	256 MB	Judgeable
Fast Food PrizesAdd up, over disjoint prize sets, the prize value times the smallest sticker count among its required kinds.	Easy2	GreedyMath+1	No attempts yet	2s	128 MB	Judgeable
MarathonerCount the listed students who finished within 6 hours and report the fastest one, breaking ties by race result order.	Easy2	ImplementationHash map	No attempts yet	2s	64 MB	Judgeable
Sequence Folding GameRepeatedly fold the list by adding symmetric pairs until two numbers remain, then Alice wins when the first is larger.	Easy2	SimulationArray	No attempts yet	1s	128 MB	Judgeable
Triangle ClassificationFor each of T triples of side lengths, output whether it is equilateral, isosceles, scalene, or not a triangle.	Easy2	Implementation	No attempts yet	1s	128 MB	Judgeable
Sanggeun's travelsGiven a connected graph of N countries and M flights, find the fewest flights that visit every country.	Easy2	Graph	No attempts yet	1s	256 MB	Judgeable
Gholam's Simple GameStarting from the marked tile and direction, walk n steps bouncing off both ends and count visits to yellow tiles.	Easy2	SimulationArray	No attempts yet	1s	128 MB	Judgeable
Arbiter LoginGiven the original and entered passwords, report login success or hint at a caps lock or num lock mistake.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Zombie InvasionProcess villages east to west, moving half of each village west and leaving at most one behind, with everything gathering on the west coast.	Easy2	SimulationMath	No attempts yet	2s	128 MB	Judgeable
Arrangement of ContestCount the titles that form the longest unbroken run from A onward, using each title's first letter and stopping at the first missing letter.	Easy2	GreedyString+1	No attempts yet	2s	256 MB	Judgeable
BoxesBoxes fall straight down in each column of a grid, and the program sums how many cells all boxes move.	Easy2	SimulationMatrix	No attempts yet	1s	256 MB	Judgeable
Von NeumannTwo trains approach each other while a fly shuttles between them, and the program prints how far the fly travels before they collide.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
The n Days of ChristmasFor each n until 0, compute the total gifts when day k of n brings k gifts down to 1.	Easy2	MathImplementation	No attempts yet	2s	128 MB	Judgeable
Perfect ShuffleInterleave the top and bottom halves of a card list to perform one perfect shuffle for each test case.	Easy2	SimulationArray	No attempts yet	1s	128 MB	Judgeable
Long is a train, a train is fast, fast is a planeCompute the travel time gap between a slower train and a faster plane over M km and print each gap as rounded H:MM:SS.	Easy2	ImplementationMath	No attempts yet	1s	128 MB	Judgeable
Text RollSimulate a ball that rolls right over non-space characters and drops down through spaces until it falls off the last line, then report its exit column.	Easy2	Simulation	No attempts yet	1s	128 MB	Judgeable
Perfect Number CheckDecide whether each given integer equals the sum of its proper divisors and print the equation or a negative verdict.	Easy2	Number theoryImplementation	No attempts yet	2s	128 MB	Judgeable
I Love CroatiaTrack the 210 seconds of answers and pass the bomb left on each correct answer to find who holds it when it explodes.	Easy2	Simulation	No attempts yet	1s	128 MB	Judgeable
Roman Catholic MassThe program seats the latecomer in the empty spot with the most occupied neighbors and counts every adjacent occupied pair once.	Easy2	Brute forceMatrix+1	No attempts yet	1s	128 MB	Judgeable
Arithmetic with MorseYou sum each Morse number from its symbol values and evaluate the expression with multiplication before addition.	Easy2	ImplementationSimulation	No attempts yet	1s	128 MB	Judgeable
Presidential ElectionEach voter ranks all candidates, and the program counts first-choice votes and then a top-two runoff to report the winner and the deciding round.	Easy2	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
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