Problems

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Total results29,460 problems

Arabiska
Medium4
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Green Card
Medium4
Math, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hockey Match
Medium4
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Boris
Medium4
Dynamic programming, Sorting
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Pick Apples
Medium4
Brute force, DFS+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Archipelago
Medium4
Graph, Union-find+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Coins
Medium4
Game theory, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Irritating accountants
Medium4
Sorting, Hash map+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
King of cans
Medium4
Math, Greedy+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Every Third Character
Medium4
Implementation, Simulation+2
No attempts yet
Time limit
0.25s
Memory limit
1024 MB
Judgeable
Line
Medium4
Math, Implementation+2
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
COURIERS
Medium4
Implementation, Math+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Clock
Medium4
Math, Number theory+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
SD Cards
Medium4
Brute force, Math+2
No attempts yet
Time limit
0.1s
Memory limit
1024 MB
Judgeable
Clock
Medium4
Math, Implementation+2
No attempts yet
Time limit
0.1s
Memory limit
1024 MB
Judgeable
Gahee and the Garbage Game
Medium4
Graph, BFS+2
No attempts yet
Time limit
3.5s
Memory limit
512 MB
Judgeable
ПАЛИНДРОМ
Medium4
String, Greedy+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Honey
Medium4
Graph, Greedy+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Number with the Most Divisors
Medium4
Number theory, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
ТОПЧЕТА
Medium4
Implementation, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Maya the Bee
Medium4
Greedy, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hexagons
Medium4
Graph, BFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
РАВЕНСТВО
Medium4
Math, Brute force+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Casting
Medium4
Math, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Muffins
Medium4
Greedy, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Salary
Medium4
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
BORDER
Medium4
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
MrCodeFormatGrader
Medium4
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Stamp Cluster Combinations
Medium4
Array, Prefix sum+2
No attempts yet
Time limit
7s
Memory limit
1024 MB
Judgeable
Tic-Tac State
Medium4
Bit manipulation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Card Game
Medium4
Brute force, Combinatorics+2
No attempts yet
Time limit
1.5s
Memory limit
512 MB
Judgeable
Algorithm Class - Breadth-First Search 1
Medium4
Graph, BFS+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Algorithm Class - Breadth-First Search 2
Medium4
Graph, BFS+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Solo Yut Nori
Medium4
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Algorithm Class - Depth-First Search 1
Medium4
DFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Algorithm Class - Depth-First Search 2
Medium4
DFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Algorithm Class - Depth-First Search 4
Medium4
DFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Algorithm Class - Depth-First Search 5
Medium4
DFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Who Owns the Prize?
Medium4
Sorting, Implementation+2
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Work Log
Medium4
Prefix sum, Array+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Downsizing
Medium4
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Good Groups
Medium4
Hash map, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tree Hopping
Medium4
BFS, Tree+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Tetris Generation
Medium4
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Boris and Berta
Medium4
Math, Number theory+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Sleeping Gyuri
Medium4
Matrix, Math+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
7 Segments You Say?
Medium4
Implementation, String+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Election Paradox
Medium4
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Odds of Mia
Medium4
Probability, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
James's Birthday Party
Medium4
Graph, DFS
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Coloring Graphs
Medium4
Graph, Backtracking+1
No attempts yet
Time limit
6s
Memory limit
1024 MB
Judgeable
Cowboy Checkers
Medium4
Simulation, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Victory Through Synergy
Medium4
Brute force, Graph+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Rock Climbing
Medium4
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bowser's Pipes
Medium4
Graph, DFS
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Holiday Stars
Medium4
Math, Simulation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Longest Palindrome
Medium4
Hash map, Greedy+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Array Interval Sum Game
Medium4
Prefix sum, Sorting+1
No attempts yet
Time limit
1.5s
Memory limit
512 MB
Judgeable
Haiku
Medium4
Prefix sum, Hash map
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Two Machines
Medium4
Greedy, Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Stocks
Medium4
Brute force, Simulation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Color the Cards
Medium4
Implementation, Greedy
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Ingredient Optimization
Medium4
Greedy, Simulation
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Interesting Outing
Medium4
Tree, DFS+1
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Card Divisibility
Medium4
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Magical Runes
Medium4
Bit manipulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Number Colosseum
Medium4
Stack, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Quadratic Dissonance
Medium4
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Buying Potions
Medium4
Bit manipulation, Dynamic programming
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Number Concatenation
Medium4
Tree, DFS+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Loop of Chocolate
Medium4
Geometry, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Counting Liars
Medium4
Sorting, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
KIARA is a Recursive Acronym
Medium4
String, Array+1
No attempts yet
Time limit
0.1s
Memory limit
1024 MB
Judgeable
Prom
Medium4
Sorting, Two pointers+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pen
Medium4
Stack, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bizmarket
Medium4
Greedy, Sorting
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Rectangle Game (Small)
Medium4
Game theory, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Automated Program Analyzer
Medium4
Union-find, Hash map
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Double or One Thing
Medium4
Greedy, String
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Sequence Conversion
Medium4
Prefix sum, Bit manipulation
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
SLOVA
Medium4
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ciphertext
Medium4
Backtracking, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Chocolate Factory
Medium4
Intervals, Greedy+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Infrastructure
Medium4
Greedy, Tree+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Audi
Medium4
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Stipe
Medium4
Array, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tired Ari and Her Real Life
Medium4
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Nervous Ari and Kugi's Card Game
Medium4
Array, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Cute and Adorable Baskin-Robbins N
Medium4
Math, Game theory
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ssum Palindrome
Medium4
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Swap the elements
Medium4
Sorting, Array+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Finding a Dongga Sequence
Medium4
Array, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
INFP Duram
Medium4
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
1, 3, 5 Segments
Medium4
Dynamic programming, Prefix sum
No attempts yet
Time limit
1.35s
Memory limit
1024 MB
Judgeable
Decisive Friday
Medium4
Dynamic programming, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Gyeongnodang Punk 2077
Medium4
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Card Trading
Medium4
Prefix sum, Sorting
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Excursion to Porvoo
Medium4
Sorting, Array
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Treehouse
Medium4
Hash map, Geometry+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Permutation Sorting
Medium4
Greedy, Array
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
ArabiskaGiven a short sentence, remove every vowel that is followed by two or more consonants and print the words in reverse order.	Medium4	StringImplementation+2	No attempts yet	1s	1024 MB	Judgeable
Green CardGiven N certified belayers and M non-certified people, all must each climb once with a distinct belayer; find the minimum total time in 10-minute rounds.	Medium4	MathGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Hockey MatchGiven partial hockey statistics for two teams, fill in every value that is uniquely determined by the constraints and leave the rest as -1.	Medium4	MathImplementation+1	No attempts yet	1s	1024 MB	Judgeable
BorisGiven trains with departure times, Boris counts, and station coordinates, find the largest total of Boris counts Philip can collect while walking at 1 m/s.	Medium4	Dynamic programmingSorting	No attempts yet	2s	1024 MB	Judgeable
Pick ApplesGiven two rows of N trees with apple counts, find the maximum apples Olga can collect starting from the bottom-left tree and walking to at most K distinct trees on the 2 by N grid.	Medium4	Brute forceDFS+2	No attempts yet	2s	1024 MB	Judgeable
ArchipelagoGiven n island coordinates and a boat range d, rank each island by how many other islands are reachable through a chain of hops of length at most d.	Medium4	GraphUnion-find+2	No attempts yet	2s	1024 MB	Judgeable
CoinsPlayers alternate removing 1 to 3 coins from a pile of n; whoever takes the last coin loses. Decide whether the first player wins with optimal play.	Medium4	Game theoryMath+2	No attempts yet	1s	1024 MB	Judgeable
Irritating accountantsSort the bought items so all items of a category appear together, and the categories follow a given order; ties within a category may be ordered any way.	Medium4	SortingHash map+1	No attempts yet	3s	1024 MB	Judgeable
King of cansGiven x bottles worth 2 kroner and y bottles worth 3 kroner, find the maximum number of groups that each sum to exactly 100.	Medium4	MathGreedy+2	No attempts yet	1s	1024 MB	Judgeable
Every Third CharacterRepeatedly delete every third character from a string and reverse it until two characters remain, then print them sorted.	Medium4	ImplementationSimulation+2	No attempts yet	0.25s	1024 MB	Judgeable
LineLate students repeatedly cut in one between every pair, and given the final count N, find the smallest possible initial number of students.	Medium4	MathImplementation+2	No attempts yet	0.5s	1024 MB	Judgeable
COURIERSGiven two delivery distances in metres, pick the cheaper of two courier price tables for each and print the minimum total cost in leva and stotinki.	Medium4	ImplementationMath+2	No attempts yet	2s	1024 MB	Judgeable
ClockCount the moments strictly inside a half-day when all three hands of a generalized clock (a hours, b minutes, c seconds per unit) coincide.	Medium4	MathNumber theory+2	No attempts yet	1s	1024 MB	Judgeable
SD CardsGiven up to four match durations, find the cheapest set of 240-minute and 180-minute SD cards whose total capacity covers all matches.	Medium4	Brute forceMath+2	No attempts yet	0.1s	1024 MB	Judgeable
ClockGiven a starting time on an analog clock and an elapsed offset, output either the current time or the minute marks the hour hand lies between.	Medium4	MathImplementation+2	No attempts yet	0.1s	1024 MB	Judgeable
Gahee and the Garbage GameGiven objects and weak or strong connections that change over time, print how many objects remain after each M or m pruning step.	Medium4	GraphBFS+2	No attempts yet	3.5s	512 MB	Judgeable
ПАЛИНДРОМGiven a string of letters, split all its characters into palindromes, using each character exactly once, and report the smallest possible number of palindromes.	Medium4	StringGreedy+2	No attempts yet	1s	1024 MB	Judgeable
HoneyPooh starts at Rabbit and must eat honey n times, each next meal at a different friend's house; find the minimum total distance traveled.	Medium4	GraphGreedy+2	No attempts yet	1s	1024 MB	Judgeable
Number with the Most DivisorsGiven n up to 3,000,000, find the smallest number in 1..n with the most positive divisors, and report that divisor count.	Medium4	Number theoryMath+2	No attempts yet	1s	1024 MB	Judgeable
ТОПЧЕТАEach step replaces every box value with the current total minus that value; after K steps, output the difference between the largest and smallest box values.	Medium4	ImplementationMath+2	No attempts yet	1s	1024 MB	Judgeable
Maya the BeeThree flowers hold A, B, C bees in nondecreasing order; move bees so each flower holds the same number, minimizing total meters flown.	Medium4	GreedyMath+2	No attempts yet	1s	1024 MB	Judgeable
HexagonsGiven slot codes for hexagons arranged in rows, find the largest group of hexagons where every hexagon can reach every other through matching slots.	Medium4	GraphBFS+1	No attempts yet	1s	1024 MB	Judgeable
РАВЕНСТВОGiven an expression X+Y=Z written in an unknown base, find the smallest base in which the equality holds.	Medium4	MathBrute force+2	No attempts yet	1s	1024 MB	Judgeable
CastingGiven counts of tall, blue-eyed, and blonde actors, find the maximum or minimum possible number who have all three traits.	Medium4	MathCombinatorics+2	No attempts yet	1s	1024 MB	Judgeable
MuffinsGiven prices, available counts of three muffin types, and a budget, find the maximum number of muffins that can be bought.	Medium4	GreedyMath+2	No attempts yet	1s	1024 MB	Judgeable
SalaryConcatenate 1^3, 2^3, 3^3, ... as decimal digits and report the k-th digit of the resulting string.	Medium4	MathImplementation+2	No attempts yet	1s	1024 MB	Judgeable
BORDERGiven rectangle sides a and b and strips of length k, find the minimum number of strips to cover the border when each side gets at most one piece from any cut strip.	Medium4	GreedyMath+1	No attempts yet	1s	1024 MB	Judgeable
MrCodeFormatGraderGiven C total lines and the N error line numbers in increasing order, print the error and correct lines as comma-separated ranges, with the last item joined by "and".	Medium4	ImplementationSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Stamp Cluster CombinationsGiven cluster sizes in a row, answer queries asking whether a target number of stamps can be formed by taking some prefix and some suffix of the clusters.	Medium4	ArrayPrefix sum+2	No attempts yet	7s	1024 MB	Judgeable
Tic-Tac StateDecode a 32-bit Tic-Tac-Toe game state from an octal number and report whether X wins, O wins, it is a cat's game, or it is still in progress.	Medium4	Bit manipulationSimulation+2	No attempts yet	1s	1024 MB	Judgeable
Card GameEach player picks k of their cards; among all possible scores, find the minimum and maximum of \|B - A\|. With n, m up to 20, brute force over all combinations works.	Medium4	Brute forceCombinatorics+2	No attempts yet	1.5s	512 MB	Judgeable
Algorithm Class - Breadth-First Search 1Run BFS from a start vertex on an unweighted undirected graph, visiting neighbors in ascending order, and report the visit order of every vertex or 0 if unreachable.	Medium4	GraphBFS+2	No attempts yet	1s	512 MB	Judgeable
Algorithm Class - Breadth-First Search 2Run BFS from a start vertex on an unweighted undirected graph, visiting neighbors in descending order, and report each vertex's visit order or 0 if unreachable.	Medium4	GraphBFS+2	No attempts yet	1s	512 MB	Judgeable
Solo Yut NoriGiven a sequence of yut throws, decide whether a single piece finishes the board within ten turns, using the short and long paths and bonus throws.	Medium4	SimulationImplementation	No attempts yet	1s	512 MB	Judgeable
Algorithm Class - Depth-First Search 1Run iterative depth-first search from vertex R on an undirected unit-weight graph, visiting neighbors in ascending order, and output each vertex's visit order or 0 if unreachable.	Medium4	DFSGraph+2	No attempts yet	1s	512 MB	Judgeable
Algorithm Class - Depth-First Search 2Given an undirected graph and a start vertex, run the supplied recursive DFS that visits neighbors in descending order, then print each vertex's visit position (0 if unreachable).	Medium4	DFSGraph+2	No attempts yet	1s	512 MB	Judgeable
Algorithm Class - Depth-First Search 4Run an iterative DFS from vertex R on an undirected graph, visiting neighbors in descending order, and print each vertex's depth in the DFS tree or -1 if unvisited.	Medium4	DFSGraph+2	No attempts yet	1s	512 MB	Judgeable
Algorithm Class - Depth-First Search 5Run iterative DFS from R visiting neighbors in ascending order, then sum depth times visit order over all reachable vertices.	Medium4	DFSGraph+2	No attempts yet	1s	512 MB	Judgeable
Who Owns the Prize?For each of four subjects in order, pick the highest-scoring student who has not yet won a prize, breaking ties by smaller student number.	Medium4	SortingImplementation+2	No attempts yet	4s	1024 MB	Judgeable
Work LogEach employee contributes i won on their i-th working day; given N work intervals, output the total revenue on each of the K days.	Medium4	Prefix sumArray+2	No attempts yet	2s	512 MB	Judgeable
DownsizingInvert a convex polygon outside a circle through the circle of radius r, then find the area of the resulting region inside the cell.	Medium4	GeometryMath	No attempts yet	1s	1024 MB	Judgeable
Good GroupsGiven same-group and separate-group constraints plus the actual groups of three, count how many constraints the grouping violates.	Medium4	Hash mapImplementation+2	No attempts yet	1s	1024 MB	Judgeable
Tree HoppingGiven a tree and a permutation of its nodes, check that every pair of consecutive nodes in the permutation is at tree distance at most three.	Medium4	BFSTree+2	No attempts yet	2s	1024 MB	Judgeable
Tetris GenerationGiven a string over the seven tetromino letters, decide whether it can appear in a sequence generated in blocks of seven, where each block is a permutation of all seven pieces.	Medium4	StringImplementation+2	No attempts yet	1s	1024 MB	Judgeable
Boris and BertaGiven a target distance n and lengths m and c, find non-negative counts of miles and cables whose total length is as close to n as possible.	Medium4	MathNumber theory+2	No attempts yet	2s	512 MB	Judgeable
Sleeping GyuriGiven Gyuri's slow recursive code for a very large N, write a faster function that returns the same value within the time limit.	Medium4	MatrixMath+1	No attempts yet	0.5s	1024 MB	Judgeable
7 Segments You Say?Given a scale factor S and a bit string of 7-bit segment codes, print each hex digit as a scaled seven segment display, wrapping cells within 80 columns.	Medium4	ImplementationString+1	No attempts yet	1s	1024 MB	Judgeable
Election ParadoxGiven odd-sized regions, find the most votes a party can receive in total while still losing the regional majority vote.	Medium4	GreedySorting+1	No attempts yet	1s	1024 MB	Judgeable
Odds of MiaGiven partly unknown dice for both players in Mia, output player 1's winning probability as a reduced fraction, or 0 or 1 when it is certain.	Medium4	ProbabilityBrute force+1	No attempts yet	1s	1024 MB	Judgeable
James's Birthday PartyGiven a friendship graph of up to 100 people, decide whether losing any single friend pair's contact would leave someone uninvited, which means checking for a bridge edge.	Medium4	GraphDFS	No attempts yet	3s	1024 MB	Judgeable
Coloring GraphsFind the minimum number of colors for a connected graph with up to 11 vertices, given as adjacency lists, so that adjacent vertices differ.	Medium4	GraphBacktracking+1	No attempts yet	6s	1024 MB	Judgeable
Cowboy CheckersGiven a Nine Men's Morris board, decide whether White has a single move that creates a double mill.	Medium4	SimulationBrute force+1	No attempts yet	1s	1024 MB	Judgeable
Victory Through SynergyPlace 10 players on the nodes of a given graph so that every node's synergy score is at least its degree, or report that no such placement exists.	Medium4	Brute forceGraph+1	No attempts yet	4s	1024 MB	Judgeable
Rock ClimbingFind the minimum energy needed to climb from any S cell to any E cell, where entering a cell changes Peter's energy by that cell's value.	Medium4	Shortest pathGraph+1	No attempts yet	1s	1024 MB	Judgeable
Bowser's PipesGiven pipes that form a functional graph ending at coin rooms, for each queried pipe find the pipe that reaches the same coin room with the fewest warp rooms, ties to smallest index.	Medium4	GraphDFS	No attempts yet	2s	1024 MB	Judgeable
Holiday StarsGiven a polygon that tumbles while following a projectile arc, find which corner reaches the wall at x = w first and the time it takes.	Medium4	MathSimulation	No attempts yet	2s	1024 MB	Judgeable
Longest PalindromePick some of the distinct equal-length strings and order them so the concatenation is the longest possible palindrome, then print one such palindrome.	Medium4	Hash mapGreedy+1	No attempts yet	1s	256 MB	Judgeable
Array Interval Sum GameRearrange array A to maximize the total of m given interval sums, then count the arrangements that reach that maximum modulo 1e9+7.	Medium4	Prefix sumSorting+1	No attempts yet	1.5s	512 MB	Judgeable
HaikuCount the runs of consecutive words that can be split into three lines holding 5, 7, and 5 phonetic units, where each unit is a run of vowels.	Medium4	Prefix sumHash map	No attempts yet	1s	512 MB	Judgeable
Two MachinesGiven commissioning times and rates for two machines, find the most parts made in k minutes when only one engineer can commission at a time.	Medium4	GreedyMath	No attempts yet	1s	512 MB	Judgeable
StocksGiven daily prices for N days, find the most money left after repeated all-in buys with K-times leverage and full sales.	Medium4	Brute forceSimulation	No attempts yet	2s	1024 MB	Judgeable
Color the CardsGiven a row of cards with some already colored, fill each 0 with red, green, or blue so adjacent cards differ, or print -1 if impossible.	Medium4	ImplementationGreedy	No attempts yet	1s	512 MB	Judgeable
Ingredient OptimizationGiven deliveries with spoil times and orders that each need U leaves, find the maximum number of orders that can be filled before the first failure.	Medium4	GreedySimulation	No attempts yet	5s	1024 MB	Judgeable
Interesting OutingGiven a weighted tree, find the minimum total edge cost of a walk that visits every node, starting and ending at any nodes.	Medium4	TreeDFS+1	No attempts yet	10s	1024 MB	Judgeable
Card DivisibilityGiven consecutive integers from L to R, find the remainder when the number formed by writing them one after another is divided by 9.	Medium4	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Magical RunesGiven a string S of A and B runes and a day count D below 2^30, the task is to print the rune states after D days.	Medium4	Bit manipulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Number ColosseumEach new contestant fights the most recent opposing contestant still inside, and the task asks which team wins and which integers remain, in arrival order.	Medium4	StackSimulation	No attempts yet	1s	1024 MB	Judgeable
Quadratic DissonanceFind the point x that minimizes the larger of two given upward parabolas with the same leading coefficient, and report x and that minimum value.	Medium4	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Buying PotionsGiven N potion prices and the discounts each purchase triggers on other potions, find the minimum total cost to buy all of them in some order.	Medium4	Bit manipulationDynamic programming	No attempts yet	3s	1024 MB	Judgeable
Number ConcatenationGiven a tree with a number on each house, answer Q queries by concatenating the door numbers along each path in order, modulo 1000000007.	Medium4	TreeDFS+1	No attempts yet	1s	512 MB	Judgeable
Loop of ChocolateCompute the volume of the union of n equal spheres whose centers form a cycle and only consecutive spheres overlap.	Medium4	GeometryMath+1	No attempts yet	2s	1024 MB	Judgeable
Counting LiarsGiven N cows that each claim Bessie is at or below, or at or above, some p_i, find the fewest cows that must be lying.	Medium4	SortingPrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
KIARA is a Recursive AcronymDecide whether some word in the list can be spelled by the first letters of distinct list words, with the word itself counted as one of them.	Medium4	StringArray+1	No attempts yet	0.1s	1024 MB	Judgeable
PromCount the pairs of one girl and one boy whose heights differ by at most k.	Medium4	SortingTwo pointers+1	No attempts yet	1s	128 MB	Judgeable
PenGiven a bracket string, add the fewest brackets at the start and end to make it a correct sequence, or print NIE if that is impossible.	Medium4	StackString	No attempts yet	1s	128 MB	Judgeable
BizmarketMatch items to client companies, at most one each, to maximize the sum of (A_i - B_j) over matched pairs, where a pair counts only if A_i is at least B_j.	Medium4	GreedySorting	No attempts yet	2s	1024 MB	Judgeable
Rectangle Game (Small)Given an N by N grid with N at most 9, find the maximum score Minwoo can guarantee when he colors rows, Jongjin colors columns, and each scores by the given rules.	Medium4	Game theoryBit manipulation+1	No attempts yet	1s	1024 MB	Judgeable
Automated Program AnalyzerFor each instance, decide whether all given equality and inequality constraints between variables with indices up to 1e9 can hold at the same time.	Medium4	Union-findHash map	No attempts yet	2s	1024 MB	Judgeable
Double or One ThingChoose which letters to double so the resulting string is alphabetically smallest, then print that string for each test case.	Medium4	GreedyString	No attempts yet	2s	1024 MB	Judgeable
Sequence ConversionGiven arrays a and b, find the fewest operations that xor two adjacent elements by the same value to turn a into b, or report -1 if impossible.	Medium4	Prefix sumBit manipulation	No attempts yet	3s	1024 MB	Judgeable
SLOVAGiven two permutations of the first N letters, find how many positions apart they are in the sorted list of all such permutations.	Medium4	CombinatoricsMath	No attempts yet	1s	1024 MB	Judgeable
CiphertextGiven a sorted key of K digits, list every 0/1 mask of positions where exactly X distinct positions have digits summing to Z.	Medium4	BacktrackingBrute force	No attempts yet	1s	1024 MB	Judgeable
Chocolate FactoryGiven K jobs that each occupy a range of machines, assign start minutes so overlapping jobs never share a minute, using the fewest minutes possible.	Medium4	IntervalsGreedy+2	No attempts yet	1s	1024 MB	Judgeable
InfrastructureDecide whether N cities can be joined by N-1 roads so each city i has exactly D_i roads, and print one such tree if it exists.	Medium4	GreedyTree+1	No attempts yet	1s	1024 MB	Judgeable
AudiCount the triples (X, Y, Z) with each value from 1 to N so that the spending satisfies AX > BY > C*Z, with all three totals distinct.	Medium4	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
StipePick K people who are each at least as old as everyone skipped, minimizing how many people are turned away before the last dose.	Medium4	ArraySorting+1	No attempts yet	1s	1024 MB	Judgeable
Tired Ari and Her Real LifeOrder N tasks, each with a repeat count R and stress S, to minimize total stress, where earlier repetitions raise the stress of later tasks.	Medium4	GreedySorting	No attempts yet	1s	512 MB	Judgeable
Nervous Ari and Kugi's Card GameCount the ranges Ari can take so that the familiar's attack and Kugi's remaining cards' health let the familiar beat the monster with attack X and health Y.	Medium4	ArrayPrefix sum+1	No attempts yet	1s	512 MB	Judgeable
Cute and Adorable Baskin-Robbins NGiven N and M, decide whether the first player can force the opponent to say N in a game where each turn says 1 to M consecutive integers.	Medium4	MathGame theory	No attempts yet	1s	1024 MB	Judgeable
Ssum PalindromeGiven N, find the fewest digits a palindrome can have while its digits sum to N (N up to 1e9).	Medium4	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Swap the elementsGiven a sequence A of N integers, rearrange it by swaps so that no position keeps its original value, or report -1 if impossible.	Medium4	SortingArray+1	No attempts yet	1s	1024 MB	Judgeable
Finding a Dongga SequenceGiven N, print any permutation of 1 to N where each pair of adjacent values differs by at least floor(N/2).	Medium4	ArrayMath+1	No attempts yet	1s	1024 MB	Judgeable
INFP DuramGiven N clothing kinds with counts d_i, decide whether everyone can stand in a circle so that no two neighbors wear the same kind.	Medium4	MathGreedy	No attempts yet	1s	1024 MB	Judgeable
1, 3, 5 SegmentsSplit a sequence of N integers into 6 contiguous segments (empty segments allowed) to maximize the sum of segments 1, 3, and 5.	Medium4	Dynamic programmingPrefix sum	No attempts yet	1.35s	1024 MB	Judgeable
Decisive FridayGiven N job durations in days, decide whether some subset of them can be ordered so the work ends exactly on Friday, 4 days after Monday.	Medium4	Dynamic programmingMath	No attempts yet	1s	1024 MB	Judgeable
Gyeongnodang Punk 2077Given the English-mode keystrokes of a Korean name typed on a 2-set keyboard, decide whether the last syllable has a final consonant.	Medium4	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Card TradingGiven buy and sell offer counts at each price, find the price that maximizes price times the number of matched trades, and report that turnover.	Medium4	Prefix sumSorting	No attempts yet	4s	1024 MB	Judgeable
Excursion to PorvooFor each car weight, find the minimum total driving time from city 1 to city n, using the fastest road each leg allows, or report impossible.	Medium4	SortingArray	No attempts yet	5s	1024 MB	Judgeable
TreehouseCount the squares, in any orientation, whose four corners all sit on tree positions among N points (N up to 2000).	Medium4	Hash mapGeometry+1	No attempts yet	3s	1024 MB	Judgeable
Permutation SortingEach element can stay as is or become N+1-x, and the task is to decide whether the sequence can be made non-decreasing.	Medium4	GreedyArray	No attempts yet	3s	1024 MB	Judgeable