Problems

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Total results29,473 problems

New Year and Naming
Easy3
Implementation, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Checks Post Facto Special Judge
Easy3
Simulation, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Time Zone
Easy3
Implementation, Math+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Hamilton Path
Easy3
Graph, Implementation
No attempts yet
Time limit
4s
Memory limit
512 MB
Judgeable
Logistical Metropolis
Easy3
Minimum spanning tree, Graph+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Drought (Small)
Easy3
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Polynomial
Easy3
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Epidemiology
Easy3
Simulation, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Cyclic Shifts
Easy3
String, String matching+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Please Write the If Statements for Me
Easy3
Binary search, Array+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Labels
Easy3
Array, Implementation+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Sudoku Variant
Easy3
Brute force, Backtracking+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Palindromic FizzBuzz
Easy3
Implementation, Math+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Sorting
Easy3
Sorting, Greedy+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
LunchBox
Easy3
Greedy, Sorting+2
No attempts yet
Time limit
0.5s
Memory limit
512 MB
Judgeable
Patterns
Easy3
Implementation, Number theory+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Anton and the School Schedule
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Big Round Table
Easy3
Math, Greedy+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Sapsan
Easy3
Math, Greedy+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Advertising on the Fence
Easy3
Intervals, Sorting+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Attractive Flowers
Easy3
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Dates
Easy3
Implementation, String+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Restoring the Sequence
Easy3
Implementation, Math+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Counting Words
Easy3
String, Implementation+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Gold Bars
Easy3
Math, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Maximum Product
Easy3
Prefix sum, Array+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Amateur Agronomist
Easy3
Array, Two pointers+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Calculating Powers of Two
Easy3
Math, Binary search+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Bard Prodigy
Easy3
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Taesang's Training Camp Life
Easy3
Prefix sum, Array+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Moon in the Photo
Easy3
Brute force, Geometry
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Race
Easy3
Math, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Computer Assembly
Easy3
Greedy, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
City of Che
Easy3
Two pointers, Array+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Rubber Duck Debugging
Easy3
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Bombs In My Deck
Easy3
Probability, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Laugh
Easy3
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Mia's Note
Easy3
Implementation, String+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Who Is the Winner of This Area?!
Easy3
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tennis
Easy3
Implementation, Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Crtanje
Easy3
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Figure Skating
Easy3
Array, Hash map+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Jam-packed
Easy3
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Pac-Man
Easy3
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Keystroke
Easy3
Brute force, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tournament turn-around
Easy3
Brute force, Probability
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Battlecheap
Easy3
Brute force, Implementation+2
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Batalha Naval
Easy3
Implementation, Simulation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Game Show!
Easy3
Prefix sum, Greedy+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Organizing Files
Easy3
String, Hash map+2
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Big Three Total
Easy3
Implementation, Array
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Divvying Up
Easy3
Math, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Cyclic Numbers
Easy3
String, Simulation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Deer Me
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Gleaming the Cubes
Easy3
Geometry, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Soundex Indexing
Easy3
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Operation Protect the Lottery Prize! (Normal)
Easy3
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Greatest Common Divisor
Easy3
Number theory, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Hotel
Easy3
Math, Brute force+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
The World Is a Single Handkerchief
Easy3
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
🐜 The Miraculous Trading Method 🐜
Easy3
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Sort Master Bae Jihoon's Successor
Easy3
Sorting, Binary search+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
General Knight
Easy3
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
AiGo
Easy3
Brute force, Simulation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Do You Know Your ABCs?
Easy3
Sorting, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Daisy Chains
Easy3
Array, Brute force+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Kate's 2021 Celebration
Easy3
Implementation, String+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Sanic
Easy3
Math, Geometry+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Complicated documents
Easy3
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Antiplagiarism
Easy3
Implementation, Matrix+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Islands
Easy3
Math, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Birthday Memorization
Easy3
Hash map, Sorting+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Treasure Map
Easy3
Simulation, Graph+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Snow Wall Checker
Easy3
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Adolescent Architecture
Easy3
Sorting, Greedy+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Palindrome Cheokhwabi
Easy3
Implementation, String+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hyojeong and the New Monitor
Easy3
Sorting, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Šifra
Easy3
String, Hash map+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Uddered but not Herd
Easy3
Greedy, String
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Uddered but not Herd
Easy3
Greedy, String+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Even More Odd Photos
Easy3
Greedy, Math+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Visible Trees
Easy3
Array, Simulation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Almost Free Falling
Easy3
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Magic Trick
Easy3
String, Hash map+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Over the Hill, Part 1
Easy3
Matrix, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
ICPC Record Matching
Easy3
Hash map, String+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
No Thanks!
Easy3
Hash map, Array+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Reconstruct Sum
Easy3
Array, Math+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
This Ain't Your Grandpa's Checkerboard
Easy3
Implementation, Array+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Stopwatch
Easy3
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Vaccine Efficacy
Easy3
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Train Boarding
Easy3
Implementation, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bold
Easy3
Implementation, Matrix+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Confused Lecturer
Easy3
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Name Day
Easy3
String, Brute force+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
le français
Easy3
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Evenly Separated Strings
Easy3
String, Hash map+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Keyboardd
Easy3
String, Two pointers+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Personnummer
Easy3
Implementation, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Biosalong
Easy3
Implementation, String+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
New Year and NamingGiven two cyclic string sequences, return the concatenation of the pair selected by each queried year index.	Easy3	ImplementationMath+2	No attempts yet	1s	1024 MB	Judgeable
Checks Post Facto Special JudgeWrite a special judge for problem 17152 that simulates the chess board from the given move record and prints the result.	Easy3	SimulationImplementation	No attempts yet	2s	512 MB	Judgeable
Time ZoneGiven a time in Beijing (UTC+8) and a target time zone string, print the corresponding 24-hour clock time.	Easy3	ImplementationMath+2	No attempts yet	1s	256 MB	Judgeable
Hamilton PathCount the permutations whose consecutive pairs are exactly the directed edges of the graph, with no other edges, and list their values when there are at most n.	Easy3	GraphImplementation	No attempts yet	4s	512 MB	Judgeable
Logistical MetropolisGiven a connected weighted graph of planets and gates, find its minimum spanning tree cost and print it N times, since the main planet does not change the answer.	Easy3	Minimum spanning treeGraph+1	No attempts yet	3s	1024 MB	Judgeable
Drought (Small)Given three target rainfall totals, find positive amounts a, b, c applied to each pair of plots so every plot hits its total exactly, or report that it is impossible.	Easy3	MathImplementation+1	No attempts yet	1s	1024 MB	Judgeable
PolynomialGiven the coefficients and degrees of a polynomial in descending order, evaluate it at x using Horner's method and print the result modulo 1e9+7.	Easy3	MathImplementation+2	No attempts yet	1s	1024 MB	Judgeable
EpidemiologySimulate a disease where each infected person infects R new people the next day, and find the first day the cumulative case count exceeds P.	Easy3	SimulationMath+1	No attempts yet	2s	512 MB	Judgeable
Cyclic ShiftsGiven a text T and a string S, decide whether T contains any cyclic shift of S as a contiguous substring.	Easy3	StringString matching+2	No attempts yet	2s	512 MB	Judgeable
Please Write the If Statements for MeGiven N titles ordered by increasing power upper bounds, print for each of M power values the first title whose bound is at least that value.	Easy3	Binary searchArray+2	No attempts yet	1s	1024 MB	Judgeable
LabelsGiven the difference sequence D of an unknown sequence A with values in [1, N], output A if it is uniquely determined, otherwise -1.	Easy3	ArrayImplementation+2	No attempts yet	2s	1024 MB	Judgeable
Sudoku VariantGiven a 3x3 grid with at most three empty cells, count the ways to fill the empties so no digit repeats in any row or column.	Easy3	Brute forceBacktracking+1	No attempts yet	2s	512 MB	Judgeable
Palindromic FizzBuzzPrint every integer from S to E, replacing any palindromic number with the string Palindrome!.	Easy3	ImplementationMath+2	No attempts yet	1s	512 MB	Judgeable
SortingGiven a list of question difficulties, determine the minimum number of adjacent swaps needed to sort them into increasing order.	Easy3	SortingGreedy+1	No attempts yet	1s	512 MB	Judgeable
LunchBoxGiven N lunch boxes and each school's request ki, choose schools to satisfy fully (all ki boxes or none) so the count of served schools is maximized.	Easy3	GreedySorting+2	No attempts yet	0.5s	512 MB	Judgeable
PatternsFill an n by n grid with 1 to n^2 in row-major order, then mark each cell with an asterisk if its number has at most k divisors, otherwise a dot.	Easy3	ImplementationNumber theory+2	No attempts yet	1s	512 MB	Judgeable
Anton and the School ScheduleGiven a Monday-to-Friday lesson grid and a sleep-deficit threshold k, find the week and day when Anton first oversleeps his first lesson, or report -1.	Easy3	SimulationImplementation	No attempts yet	1s	512 MB	Judgeable
Big Round TableMasha sits at a round table of n seats and makes exactly k swaps with a left or right neighbor; count the seats she could occupy at the end.	Easy3	MathGreedy+1	No attempts yet	1s	512 MB	Judgeable
SapsanGiven a row of n seats split into n/2 adjacent pairs, find the largest number of occupied seats so that exactly half the seated people sit next to an occupied neighbor.	Easy3	MathGreedy+1	No attempts yet	2s	512 MB	Judgeable
Advertising on the FenceGiven n intervals over boards 1 to m, decide whether their union covers every board from 1 to m.	Easy3	IntervalsSorting+1	No attempts yet	2s	512 MB	Judgeable
Attractive FlowersGiven the stock of each flower type, pick an odd count from each type so the total is odd and as large as possible.	Easy3	GreedyMath+1	No attempts yet	1s	512 MB	Judgeable
DatesEach input line is a date in day.month.year or month/day/year format; print both formats, validating that the date actually exists.	Easy3	ImplementationString+2	No attempts yet	1s	512 MB	Judgeable
Restoring the SequenceGiven n, m, and m board values, decide whether they are 1..n with exactly one number erased, and print that number.	Easy3	ImplementationMath+2	No attempts yet	1s	512 MB	Judgeable
Counting WordsSplit a sentence on spaces and hyphens, then split any token that looks like a French contraction (c', j', n', m', t', s', l', d', qu' followed by a vowel) into two words, and count the total.	Easy3	StringImplementation+2	No attempts yet	2s	1024 MB	Judgeable
Gold BarsGiven three bar weights with an even total, decide whether the bars already split evenly, or which single bar to cut in two so the pieces divide equally.	Easy3	MathImplementation+2	No attempts yet	2s	512 MB	Judgeable
Maximum ProductSplit the array after one index so the product of the two part sums is maximized, and print that index.	Easy3	Prefix sumArray+2	No attempts yet	2s	512 MB	Judgeable
Amateur AgronomistFind the longest contiguous segment of a flower row that does not contain three equal values in a row, and print its start and end indices.	Easy3	ArrayTwo pointers+2	No attempts yet	2s	512 MB	Judgeable
Calculating Powers of TwoGiven the final value Taeyoung got after subtracting 1 once during his powers-of-two computation, find which step K he made that mistake at.	Easy3	MathBinary search+2	No attempts yet	1s	512 MB	Judgeable
Bard ProdigyGiven a poem and per-key press limits, decide whether the poem plus its derived title (first letter of each word, uppercased) can be typed, counting runs of equal keys as one press, and print the title or -1.	Easy3	StringImplementation+1	No attempts yet	1s	512 MB	Judgeable
Taesang's Training Camp LifeApply M range updates that add a signed value to each cell in a range, then print every final cell height.	Easy3	Prefix sumArray+1	No attempts yet	1s	512 MB	Judgeable
Moon in the PhotoFind the largest circle that contains no black pixels in a grid of white and black points, and print its radius and center as column then row.	Easy3	Brute forceGeometry	No attempts yet	2s	512 MB	Judgeable
RaceEach car alternates between driving for t hours at v km/h and charging for t hours; compare which one covers x km first.	Easy3	MathImplementation+1	No attempts yet	2s	512 MB	Judgeable
Computer AssemblyGiven counts of VGA-only, DVI-only, and dual-interface units and monitors, find the maximum number of pairable unit-monitor sets.	Easy3	GreedyMath+1	No attempts yet	2s	512 MB	Judgeable
City of CheGiven sorted monument positions and a distance r, count the pairs of monuments whose distance apart is greater than r.	Easy3	Two pointersArray+2	No attempts yet	2s	512 MB	Judgeable
Rubber Duck DebuggingTrack a count of unsolved problems: '문제' adds one, '고무오리' removes one or adds two when the count is zero, then report whether the count is zero.	Easy3	ImplementationSimulation+1	No attempts yet	1s	512 MB	Judgeable
Bombs In My DeckGiven a deck of A cards with B bombs, find the probability that drawing cards until a non-bomb appears never drops HP (C, 5 per bomb) to 0 or below.	Easy3	ProbabilityCombinatorics+2	No attempts yet	1s	1024 MB	Judgeable
LaughGiven a string, find the length of the longest substring made of alternating h and a characters.	Easy3	StringImplementation+2	No attempts yet	1s	512 MB	Judgeable
Mia's NoteGiven an H by N*W grid formed by smearing a length-N string, fill in each original character from any non-'?' cells and mark the rest '?'.	Easy3	ImplementationString+2	No attempts yet	1s	256 MB	Judgeable
Who Is the Winner of This Area?!Map each letter of a string to its stroke count, repeatedly sum adjacent pairs modulo 10, and report whether the final single value is odd.	Easy3	SimulationImplementation+2	No attempts yet	1s	1024 MB	Judgeable
TennisGiven three rankings of n players, each pair plays on the court where the winner ranks highest. Count matches per court and wins per player.	Easy3	ImplementationArray	No attempts yet	1s	512 MB	Judgeable
CrtanjeGiven a string of +, -, = changes to a value starting at 0, place the corresponding /, \, _ characters in a grid and print the minimal bounding matrix.	Easy3	ImplementationSimulation+2	No attempts yet	1s	512 MB	Judgeable
Figure SkatingGiven a predicted and a final ranking of n skaters, find the skater who climbed the most places; if nobody climbed, print suspicious.	Easy3	ArrayHash map+1	No attempts yet	1s	512 MB	Judgeable
Jam-packedGiven n jars and boxes holding up to k, distribute all jars so the emptiest box holds as many jars as possible, and report that count.	Easy3	MathGreedy	No attempts yet	1s	512 MB	Judgeable
Pac-ManOutput a walk on a 10 by 10 grid starting at a given cell that visits all 100 cells within 10000 steps.	Easy3	SimulationImplementation+2	No attempts yet	1s	1024 MB	Judgeable
KeystrokeCount how many subsets of the four keys can produce the given set of received row numbers and set of received column numbers.	Easy3	Brute forceCombinatorics+2	No attempts yet	1s	1024 MB	Judgeable
Tournament turn-aroundGiven head-to-head win counts for eight teams, find the bracket order that maximizes team 1's chance of winning the tournament.	Easy3	Brute forceProbability	No attempts yet	5s	512 MB	Judgeable
BattlecheapCount placements of a length-3 ship on a 10 by 10 grid that avoid being fully hit by a given sequence of distinct shots.	Easy3	Brute forceImplementation+2	No attempts yet	3s	512 MB	Judgeable
Batalha NavalGiven N ships described by direction, length, and starting cell on a 10x10 board, decide whether all ships fit inside the board without overlapping.	Easy3	ImplementationSimulation+2	No attempts yet	2s	512 MB	Judgeable
Game Show!Given a sequence of box values, a player starts at 100 and may stop at any point; find the maximum balance reachable.	Easy3	Prefix sumGreedy+2	No attempts yet	2s	512 MB	Judgeable
Organizing FilesGiven N file names, count how many files share each extension and print the extensions in lexicographic order with their counts.	Easy3	StringHash map+2	No attempts yet	3s	1024 MB	Judgeable
Big Three TotalCount teams whose three members each have rating at least L and whose ratings sum to at least K, then print the members of each qualifying team.	Easy3	ImplementationArray	No attempts yet	3s	1024 MB	Judgeable
Divvying UpGiven prize amounts from n contests, decide whether each total can be split among three team members so all three end with equal sums.	Easy3	MathImplementation+2	No attempts yet	2s	512 MB	Judgeable
Cyclic NumbersGiven a list of digit strings up to 1000 digits long, the task checks whether each number is cyclic, meaning its multiples by 1 to n are rotations of its digits.	Easy3	StringSimulation+1	No attempts yet	1s	512 MB	Judgeable
Deer MeSimulate a county's deer herd for N years using yearly birth, survival, and harvest rates, rounding each year's total to the nearest integer.	Easy3	SimulationImplementation	No attempts yet	1s	512 MB	Judgeable
Gleaming the CubesGiven several sets of axis-aligned cubes, compute for each set the volume of the region shared by all cubes in that set.	Easy3	GeometryImplementation+1	No attempts yet	1s	512 MB	Judgeable
Soundex IndexingFor each uppercase name, produce its Soundex code (letter plus three digits), skipping vowels and merging repeated codes, and print names and codes in fixed columns.	Easy3	StringImplementation+1	No attempts yet	1s	512 MB	Judgeable
Operation Protect the Lottery Prize! (Normal)Given a prime m and three values Seed, X1, X2 with X1 = (aSeed+c) mod m and X2 = (aX1+c) mod m, find any valid a and c.	Easy3	MathNumber theory+1	No attempts yet	1s	512 MB	Judgeable
Greatest Common DivisorGiven n numbers, choose a subset whose greatest common divisor is exactly d, or report -1 if no such subset exists.	Easy3	Number theoryImplementation	No attempts yet	2s	512 MB	Judgeable
HotelGiven a delegation of n people, find the minimum number of double and triple rooms that hold exactly n people with no free beds.	Easy3	MathBrute force+1	No attempts yet	2s	512 MB	Judgeable
The World Is a Single HandkerchiefA walker starts at the origin heading along +x and turns 90 degrees left or right at given times; find the position after T seconds.	Easy3	ImplementationSimulation+2	No attempts yet	1s	1024 MB	Judgeable
🐜 The Miraculous Trading Method 🐜Given 14 daily stock prices and equal starting cash, simulate Junhyeon's buy-and-hold strategy and Seongmin's all-in/all-out timing strategy, then compare final assets.	Easy3	SimulationImplementation+2	No attempts yet	1s	512 MB	Judgeable
Sort Master Bae Jihoon's SuccessorSort the array A into B, then for each query D print the first index where D appears in B, or -1 if it is absent.	Easy3	SortingBinary search+1	No attempts yet	2s	512 MB	Judgeable
General KnightGiven an (a,b)-knight and a start square, list every square it can reach in one move, sorted by column then row.	Easy3	SimulationImplementation+2	No attempts yet	1s	1024 MB	Judgeable
AiGoGiven a 1D Go board, find the most black stones white can capture with one legal move, where white may not place a stone that forms an enclosed white chain.	Easy3	Brute forceSimulation+1	No attempts yet	2s	512 MB	Judgeable
Do You Know Your ABCs?Given seven numbers that are A, B, C and their pairwise and total sums in some order, recover the three sorted positive integers.	Easy3	SortingMath+1	No attempts yet	1s	512 MB	Judgeable
Daisy ChainsCount subarrays whose average equals the value of some element inside that subarray.	Easy3	ArrayBrute force+2	No attempts yet	1s	512 MB	Judgeable
Kate's 2021 CelebrationGiven packs of balloons, each with a price and a digit string, find the cheapest single pack that contains the digits 2, 0, 2, 1.	Easy3	ImplementationString+2	No attempts yet	2s	512 MB	Judgeable
SanicGiven the loop radius r (Sanic's radius is 1), compute how many revolutions Sanic makes while rolling once around the inside of the loop.	Easy3	MathGeometry+2	No attempts yet	1s	1024 MB	Judgeable
Complicated documentsAdd the minimum number of spaces to each line so every colon and dash has a space or a line boundary on both sides.	Easy3	StringImplementation+2	No attempts yet	1s	256 MB	Judgeable
AntiplagiarismGiven two N by N grids of '*' and '#', decide whether one can be turned into the other by rotations of 90 degrees and mirror reflections.	Easy3	ImplementationMatrix+2	No attempts yet	1s	256 MB	Judgeable
IslandsContestants disappear on islands following a Fibonacci-like rule, and we must find the island where the Nth contestant vanishes.	Easy3	MathSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Birthday MemorizationGiven friends with distinct like-scores and birthdays, keep only the highest-scoring friend for each date and print the survivors' names in alphabetical order.	Easy3	Hash mapSorting+2	No attempts yet	1s	1024 MB	Judgeable
The Treasure MapFollow arrows from the top-left cell of a grid until reaching sushi, the samurai, or a cell visited before.	Easy3	SimulationGraph+2	No attempts yet	1s	1024 MB	Judgeable
Snow Wall CheckerGiven wall rows listed from bottom to top, decide whether each block has supports at its two endpoints in the row below, and whether no two consecutive rows share a gap.	Easy3	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
Adolescent ArchitectureGiven cubes and cylinders, order them top to bottom so each block fits inside the one below it, or report that no order works.	Easy3	SortingGreedy+2	No attempts yet	1s	512 MB	Judgeable
Palindrome CheokhwabiGiven N, print any length-N lowercase string that is both a palindrome and has identical front and back halves.	Easy3	ImplementationString+2	No attempts yet	1s	1024 MB	Judgeable
Hyojeong and the New MonitorGiven N monitors with the same 77-inch diagonal, print their indices sorted by decreasing PPI, breaking ties by smaller index.	Easy3	SortingMath+1	No attempts yet	1s	1024 MB	Judgeable
ŠifraGiven a short word of lowercase letters and digits, count how many distinct integers appear when letters are treated as separators.	Easy3	StringHash map+2	No attempts yet	1s	512 MB	Judgeable
Uddered but not HerdFind the fewest copies of the cowphabet needed to contain the heard string as a subsequence, where the cowphabet is a fixed reordering of a to z.	Easy3	GreedyString	No attempts yet	2s	512 MB	Judgeable
Uddered but not HerdGiven a permutation of the 26 letters and a string, count how many times the full alphabet must repeat so the string is a subsequence of the repetition.	Easy3	GreedyString+2	No attempts yet	1s	512 MB	Judgeable
Even More Odd PhotosPartition all cows into the maximum number of groups whose breed-ID sums alternate even, odd, even, and so on, starting with even.	Easy3	GreedyMath+2	No attempts yet	1s	512 MB	Judgeable
Visible TreesFor each column count trees taller than every tree before them when scanning north to south, and for each row do the same scanning west to east.	Easy3	ArraySimulation+1	No attempts yet	1s	512 MB	Judgeable
Almost Free FallingGiven mass, two air-resistance constants, parachute time, and height, compute Bob's fallen distance at query times and the total fall time.	Easy3	MathImplementation+2	No attempts yet	1s	512 MB	Judgeable
Magic TrickGiven a string of letters, decide whether swapping two cards (or doing nothing) can always be identified from the resulting arrangement.	Easy3	StringHash map+2	No attempts yet	1s	512 MB	Judgeable
Over the Hill, Part 1Given an n by n matrix and a plaintext, encode the text using Hill cipher over a 37 character alphabet with modular arithmetic.	Easy3	MatrixMath+2	No attempts yet	1s	1024 MB	Judgeable
ICPC Record MatchingMatch two lists of name and email records by exact email or exact first and last name, ignoring case, then print unmatched records sorted by email.	Easy3	Hash mapString+2	No attempts yet	1s	1024 MB	Judgeable
No Thanks!Given a set of distinct card numbers, score the pile as the sum of each card that does not have a consecutive predecessor among the collected cards.	Easy3	Hash mapArray+1	No attempts yet	1s	512 MB	Judgeable
Reconstruct SumGiven a list of integers, find one element that equals the sum of all the other elements, or report that none exists.	Easy3	ArrayMath+2	No attempts yet	1s	512 MB	Judgeable
This Ain't Your Grandpa's CheckerboardGiven an even n by n grid of black and white squares, decide whether every row and column has equal black and white counts and no three same-colored squares in a row.	Easy3	ImplementationArray+2	No attempts yet	1s	1024 MB	Judgeable
StopwatchGiven the increasing times when a stopwatch button toggles the timer, report the total running seconds, or that the timer is still running.	Easy3	SimulationImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Vaccine EfficacyGiven N participants marked as vaccinated or control and infected by strains A, B, C, compute each strain's vaccine efficacy as a percentage reduction in infection rate, or print Not Effective.	Easy3	ImplementationMath+1	No attempts yet	1s	1024 MB	Judgeable
Train BoardingEach passenger walks to the door at the center of the nearest car, breaking ties toward the higher-numbered car; report the longest walk and the busiest car's passenger count.	Easy3	ImplementationMath+2	No attempts yet	1s	1024 MB	Judgeable
BoldExpand each '#' in an n by m grid into a 2x2 block extending right and down, and print the resulting grid.	Easy3	ImplementationMatrix+2	No attempts yet	1s	512 MB	Judgeable
Confused LecturerGiven the number of scheduled lectures per week, Bjarki repeats the previous week's count, so count how many lectures he gives to empty rooms and how many he misses.	Easy3	ImplementationSimulation+1	No attempts yet	1s	512 MB	Judgeable
Name DayGiven a name and a list of the year's name days, find the earliest day reachable by replacing exactly one letter of the name.	Easy3	StringBrute force+2	No attempts yet	1s	1024 MB	Judgeable
le françaisCount the alphabetic letters in a French sentence, then print the multiple of seven closest to that count, spelled out in French words with lowercase letters and spaces.	Easy3	StringImplementation+2	No attempts yet	1s	512 MB	Judgeable
Evenly Separated StringsDecide whether every pair of equal characters in the string has an even number of characters strictly between them.	Easy3	StringHash map+1	No attempts yet	1s	512 MB	Judgeable
KeyboarddGiven a typed string and the displayed string where each sticky key's character was doubled, find every character that must be sticky.	Easy3	StringTwo pointers+2	No attempts yet	1s	1024 MB	Judgeable
PersonnummerConvert a ten-digit Swedish personal identity number with a separator into twelve-digit YYYYMMDDXXXX form, using the separator to decide the birth century.	Easy3	ImplementationMath+2	No attempts yet	1s	1024 MB	Judgeable
BiosalongGiven a row of seats marked free or occupied, print the smallest number of seats between any two free seats.	Easy3	ImplementationString+1	No attempts yet	2s	1024 MB	Judgeable