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Total results2,362 problems

Units Digit of a Power of Two
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rhyming Verses
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Park
Easy2
Prefix sum, Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Bagels on a Stick
Easy2
Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Hidden Number
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Caesar Cipher
Easy2
String, Array+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Warehouse
Easy2
Array, Simulation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Non-Divisors
Easy2
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sums and Differences
Easy2
Math, Combinatorics
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Step on the Foot
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Kwadrat
Easy2
Geometry, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dividing the Chocolate Bar
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Overlapping Rectangle Area
Easy2
Geometry
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Little Snowman
Easy2
Math, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bouncing Ball
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Ranking Manipulation
Easy2
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Making Grid Paper
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Thumbtacks
Easy2
Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Chess
Easy2
Greedy, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Paints
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pear Trees and Apple Trees
Easy2
Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tournament
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Missing Digits
Easy2
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Closing the Circuit
Easy2
Implementation, Sorting+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Mondays
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Karaoke
Easy2
Sliding window, String
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Palindrome Coloring
Easy2
String, Two pointers
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rock Paper Scissors
Easy2
Probability, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Shoe Factory
Easy2
Prefix sum, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bookmakers
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Power Strips
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Changing a Light Bulb
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rock Paper Scissors
Easy2
Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Turtle
Easy2
Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sales
Easy2
Brute force, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Molar Mass
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Careless Addition
Easy2
Implementation, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Heeju's Math Exam
Easy2
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Guess the Song
Easy2
Simulation, Hash map
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Display
Easy2
Array, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Train
Easy2
Simulation, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Olympic Country Ranking
Easy2
Sorting, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Old Bill
Easy2
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Clock
Easy2
Math, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Display
Easy2
Greedy, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Decryption
Easy2
Array, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
War Game
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tidying the Banquet Tables
Easy2
Brute force, Matrix
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mathematical Curiosity
Easy2
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Addition in Different Bases
Easy2
Implementation, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Woodworms
Easy2
Matrix, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Air speed of a fully laden swallow
Easy2
Implementation, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sir Bedavere's Bogus Division
Easy2
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Taunt Exposure Estimation
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Consecutive Digits in a Rational Number
Easy2
Simulation, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pig Latin
Easy2
String, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
W**h y**r mouth out with s**p
Easy2
String, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Check Digits
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Word Ladder
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Crossword Puzzle Clue Numbering
Easy2
Simulation, Matrix+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Friend of My Enemy Is My Enemy
Easy2
Graph, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
More Dice
Easy2
Brute force, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Morse Code
Easy2
Hash map, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Winning at tic-tac-toe
Easy2
Brute force, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Reducing Improper Fractions
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Painting Party
Easy2
Simulation, Matrix
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Geometric Inflation
Easy2
Simulation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Arithmetic and Geometric Sums
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Integer Flipping
Easy2
Bit manipulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Monitor DPI
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Ironclad Security Algorithm
Easy2
Hash map, Array
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Fast Food Prizes
Easy2
Greedy, Math+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Marathoner
Easy2
Implementation, Hash map
No attempts yet
Time limit
2s
Memory limit
64 MB
Judgeable
Sequence Folding Game
Easy2
Simulation, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Triangle Classification
Easy2
Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sanggeun's travels
Easy2
Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Gholam's Simple Game
Easy2
Simulation, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Arbiter Login
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Zombie Invasion
Easy2
Simulation, Math
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Arrangement of Contest
Easy2
Greedy, String+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Boxes
Easy2
Simulation, Matrix
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Von Neumann
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The n Days of Christmas
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Perfect Shuffle
Easy2
Simulation, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Long is a train, a train is fast, fast is a plane
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Text Roll
Easy2
Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Perfect Number Check
Easy2
Number theory, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
I Love Croatia
Easy2
Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Roman Catholic Mass
Easy2
Brute force, Matrix+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Arithmetic with Morse
Easy2
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Presidential Election
Easy2
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Kids love candy
Easy2
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Contest Venue Setup
Easy2
Matrix, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Combination Lock
Easy2
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Vicinity
Easy2
Brute force, Geometry
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stone Game 5
Easy2
Game theory, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Show Me The Operators
Easy2
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Anti-Arithmetic Permutation
Easy2
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fibonacci remainder
Easy2
Math, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Qurban 2011
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
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
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