Problems

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Total results29,441 problems

Santa Chunbae's Gift Distribution
Medium5
Greedy, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Chunbae's Special Heart
Medium5
Divide and conquer, Recursion+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Stacking Plates
Medium5
Array, Stack+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Re-verse
Medium5
String matching, Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Reavers
Medium5
Graph, Union-find+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Electronic Components
Medium5
Greedy, Sorting
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Paper Folding
Medium5
Geometry, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Reafy Sequence
Medium5
Number theory, Math+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
No Room Left to Retreat
Medium5
Game theory, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
MEXchange
Medium5
Greedy, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Wasting time
Medium5
Dynamic programming, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hobanwoo's Reason for Being Late to School 3
Medium5
Stack, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Candy Rush
Medium5
Sliding window, Hash map+1
No attempts yet
Time limit
2.5s
Memory limit
1024 MB
Judgeable
Forward and Backward
Medium5
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Battle Bots
Medium5
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Compressing Commands
Medium5
Trie, Tree+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Funicular Frenzy
Medium5
Array, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Jungle Job
Medium5
Tree, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Circular Notes Without Zero Adjacent Sums
Medium5
Math, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rigged Rock-Paper-Scissors (Small)
Medium5
Dynamic programming, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rigged Rock-Paper-Scissors (Large)
Medium5
Dynamic programming, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Mike Sees The Storm (Small)
Medium5
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
OR & XOR (Small)
Medium5
Bit manipulation, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
A Pivotal Question
Medium5
Array, Prefix sum
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Forest for the Trees
Medium5
Hash map, Brute force+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Split Decisions
Medium5
Hash map, String+1
No attempts yet
Time limit
6s
Memory limit
1024 MB
Judgeable
A (Fast) Walk in the Woods
Medium5
Simulation, Graph+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Siru's Walk
Medium5
Geometry, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Gas Station
Medium5
Simulation, Queue+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Scrabble Flash
Medium5
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Delivery Forces
Medium5
Greedy, Sorting
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Kernel Scheduler
Medium5
Graph, Topological sort+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Beth's Cookies
Medium5
Stack, Recursion+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Screamers in the Storm
Medium5
Dynamic programming, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Dinner for Introverts
Medium5
Math, Greedy
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Bad Bets
Medium5
Math, Probability
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Monster Mask
Medium5
Geometry, Two pointers
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Greatest Greatest Common Divisor
Medium5
Number theory, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Margo Leaves Megabyteburg
Medium5
BFS, Graph+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Snakes&Snakes
Medium5
BFS, Shortest path+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Divisibility Trick
Medium5
Math, Number theory
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Kitchen Timer
Medium5
Greedy, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Weather Trends
Medium5
Sliding window, Queue+1
No attempts yet
Time limit
20s
Memory limit
1024 MB
Judgeable
Huh? Banned
Medium5
Dynamic programming, Binary search+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rush & Slash
Medium5
Union-find, Hash map+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Doll Exhibition
Medium5
Hash map, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Each to Their Own Square
Medium5
Hash map, Geometry
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Rush Hour
Medium5
Graph, BFS
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Drunkard's Path
Medium5
Probability, Matrix+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Archipelago
Medium5
Backtracking, Brute force+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Strange sum
Medium5
Hash map, Sorting+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Integral Array
Medium5
Prefix sum, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Submitting Assignments
Medium5
Brute force, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cartel Nim Game
Medium5
Game theory, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Return of the Poop Game
Medium5
Greedy, Sorting
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Coloring the Flag
Medium5
Matrix, BFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Up and Down
Medium5
Array, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Olympiad
Medium5
Binary search, Sorting
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Olympiad
Medium5
Math, Greedy
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Metro
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Nested Candy Boxes
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Gleb and Two Numbers
Medium5
String, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Clean Socks
Medium5
Sorting, Greedy
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Keyboard and Virus
Medium5
Hash map, Combinatorics+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
DDR
Medium5
Dynamic programming, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Gahui and Sousenkyo 4
Medium5
Math, Greedy+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
gahui and sousenkyo 6
Medium5
Bit manipulation, Math+1
No attempts yet
Time limit
1.5s
Memory limit
512 MB
Judgeable
Gahee and the Tunnel
Medium5
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Lexicographically Largest Common Subsequence
Medium5
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sum of Intersection Sizes
Medium5
Combinatorics, Hash map
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Geongong String
Medium5
Simulation, String+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
That Long Number
Medium5
Math, Binary search+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Subsequence MEX
Medium5
Dynamic programming, String+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tourist Petr
Medium5
Graph, Brute force+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
A Little Tale About a Purple Beaver
Medium5
Array, Prefix sum+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Big Numbers for Little Vasya
Medium5
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Vasya and the Apartments
Medium5
Math, Binary search
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fruitful cooperation
Medium5
Dynamic programming, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Vasya and Cyclic Shifts
Medium5
String, String matching
No attempts yet
Time limit
0.6s
Memory limit
1024 MB
Judgeable
A Million Scarlet Roses
Medium5
Dynamic programming, Array+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Odd Nim
Medium5
Game theory, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Colonization
Medium5
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Reckless Speleologists
Medium5
Graph, Shortest path
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
XOR Queries
Medium5
Trie, Bit manipulation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Too Many Assignments
Medium5
String, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hanyang Popularity Exceeding Competition
Medium5
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Meeting Time
Medium5
Probability, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Queries are not locks
Medium5
Segment tree, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Escape the Ghost House
Medium5
BFS, Simulation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Fixing Fractions
Medium5
String, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Wiing Wiing
Medium5
Sorting, Geometry
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
A+B - 10 (Part 2)
Medium5
Binary search, Math+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Flooding
Medium5
Array, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Group Project
Medium5
Sorting, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Minimum and Maximum
Medium5
Math, Sorting+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Sensor
Medium5
Geometry, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Super Bus
Medium5
Shortest path, Graph+1
No attempts yet
Time limit
1.5s
Memory limit
512 MB
Judgeable
A Slightly Slow but Kind Friend
Medium5
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Avoid the bomb shot! Blue Padaengi!
Medium5
Dynamic programming, Intervals+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
充成! Paran's Daengdaengi
Medium5
Matrix, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Santa Chunbae's Gift DistributionGiven N gifts priced from 0 to 3, pair them into N/2 pairs so that the sum of the XOR values of the pairs is as large as possible.	Medium5	GreedyImplementation	No attempts yet	1s	1024 MB	Judgeable
Chunbae's Special HeartGiven N and M, decide whether repeatedly splitting a heart into floor and ceiling halves and keeping one half can end at exactly M grams.	Medium5	Divide and conquerRecursion+1	No attempts yet	1s	1024 MB	Judgeable
Stacking PlatesGiven N plates of thickness 1 or 2, merge adjacent equal plates into one doubled plate to find the largest thickness that can be reached.	Medium5	ArrayStack+1	No attempts yet	1s	1024 MB	Judgeable
Re-verseGiven a song string of length N, find the maximum number of start seconds from 0 to N-1 where the song can be sung so that overlapping shouted letters agree.	Medium5	String matchingMath	No attempts yet	1s	512 MB	Judgeable
ReaversGiven each person's claim about another person's identity, find the fewest aliens that fit all the reports, with at least one human present.	Medium5	GraphUnion-find+1	No attempts yet	1s	512 MB	Judgeable
Electronic ComponentsGiven N component types with counts and placement times, find the minimum total time to place all components when two different types can be placed in one move.	Medium5	GreedySorting	No attempts yet	4s	1024 MB	Judgeable
Paper FoldingGiven a rectangle and a fold line through two points on different edges, the task is to find the area of the folded paper's outline, truncated to an integer.	Medium5	GeometryImplementation	No attempts yet	1s	1024 MB	Judgeable
Reafy SequenceGiven n and k, print the k-th irreducible fraction between 0 and 1 whose denominator is at most n, as two numbers a and b.	Medium5	Number theoryMath+1	No attempts yet	0.5s	1024 MB	Judgeable
No Room Left to RetreatDuck and Goose alternate moving or attacking on a row of N cells, starting from opposite ends; print who wins with optimal play.	Medium5	Game theoryMath	No attempts yet	1s	1024 MB	Judgeable
MEXchangeGiven the prefix MEX sequence B, construct a permutation A that produces B, or report that no such permutation exists.	Medium5	GreedyImplementation	No attempts yet	1s	1024 MB	Judgeable
Wasting timeFind the longest time to first reach cell N from cell 1 when each cell's number sets the move length and at most two direction reversals are allowed.	Medium5	Dynamic programmingGraph+1	No attempts yet	1s	1024 MB	Judgeable
Hobanwoo's Reason for Being Late to School 3Logs are added in increasing length, and each spell cuts the longest log down to a threshold. Find the total length of the logs left after all N queries.	Medium5	StackSimulation	No attempts yet	1s	1024 MB	Judgeable
Candy RushFind the longest contiguous block of candies that contains exactly K brands, with each brand appearing the same number of times.	Medium5	Sliding windowHash map+1	No attempts yet	2.5s	1024 MB	Judgeable
Forward and BackwardGiven N up to 10^12, list every base from 2 to N in which N reads the same forward and backward, in increasing order.	Medium5	Number theoryMath+1	No attempts yet	1s	1024 MB	Judgeable
Battle BotsGiven how many claw attacks would crush the opponent bot, find the fewest sword and claw attacks needed in the worst case to destroy it.	Medium5	MathGreedy	No attempts yet	1s	1024 MB	Judgeable
Compressing CommandsGiven n absolute file paths, find the working directory that minimizes the total number of components in their relative forms.	Medium5	TrieTree+1	No attempts yet	2s	1024 MB	Judgeable
Funicular FrenzyGiven arrivals per minute and carriage capacity c, find the arrival minute that minimizes your funicular wait, earliest on ties, or report impossible.	Medium5	ArrayPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Jungle JobCount the connected subtrees of a rooted tree with n branches for each size k from 1 to n, modulo 1e9+7.	Medium5	TreeDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Circular Notes Without Zero Adjacent SumsCount the ways to write 1, -1, 2, or -2 on N students at a round table so that no two neighbors sum to 0, modulo 1e9+3.	Medium5	MathDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Rigged Rock-Paper-Scissors (Small)Count the non-empty subsequences of a rock-paper-scissors move string where no round won by lighter is immediately followed by a tie.	Medium5	Dynamic programmingString	No attempts yet	1s	1024 MB	Judgeable
Rigged Rock-Paper-Scissors (Large)Count the non-empty subsequences of smallant's moves where lighter, copying the previous move, never wins a round followed by a tie.	Medium5	Dynamic programmingString	No attempts yet	1s	1024 MB	Judgeable
Mike Sees The Storm (Small)Starting from 0, Mike makes N up-steps and N down-steps in every possible order, and the task is to sum each walk's maximum value modulo 1000000007.	Medium5	CombinatoricsMath	No attempts yet	1s	1024 MB	Judgeable
OR & XOR (Small)Given sequences A and B, change p of the N^2 XOR operations to OR to maximize the total sum, with each value below 1024.	Medium5	Bit manipulationMath+1	No attempts yet	2s	1024 MB	Judgeable
A Pivotal QuestionGiven an array of unique integers, list every value that could be a quicksort pivot, meaning all elements before it are smaller and all elements after it are larger.	Medium5	ArrayPrefix sum	No attempts yet	2s	1024 MB	Judgeable
Forest for the TreesGiven a map of tree coordinates and sensor readings taken at an unknown heading, find the robot's grid position, or report Impossible or Ambiguous.	Medium5	Hash mapBrute force+1	No attempts yet	2s	1024 MB	Judgeable
Split DecisionsCount the word pairs that differ in exactly two adjacent letters, where no other pair in the list fits that same letter clue.	Medium5	Hash mapString+1	No attempts yet	6s	1024 MB	Judgeable
A (Fast) Walk in the WoodsSimulate Brice's jog on a grid of paths with usage limits, choosing turns by his rules, and report the coordinates where the jog ends.	Medium5	SimulationGraph+1	No attempts yet	2s	1024 MB	Judgeable
Siru's WalkGiven pillars on a plane and circular smell zones from other dogs, count the most pillars Siru can mark with its own smell of radius R0.	Medium5	GeometryBrute force	No attempts yet	1s	1024 MB	Judgeable
Gas StationSimulate cars choosing pump lanes across P columns under fixed queueing rules, and output the time each car leaves the station.	Medium5	SimulationQueue+1	No attempts yet	1s	1024 MB	Judgeable
Scrabble FlashFind the most words you can chain from a start word within U seconds, where each step's cost depends on the longest common substring with the previous word.	Medium5	Dynamic programmingBit manipulation+1	No attempts yet	4s	1024 MB	Judgeable
Delivery ForcesSplit n couriers (n is a multiple of 3) into teams of three to maximize the sum of each team's median strength.	Medium5	GreedySorting	No attempts yet	2s	1024 MB	Judgeable
Kernel SchedulerGiven n tasks and m directed dependencies, keep at least m/2 of them so that the kept dependencies contain no cycle and print their ids.	Medium5	GraphTopological sort+1	No attempts yet	2s	1024 MB	Judgeable
Beth's CookiesGiven a bracket sequence, insert operators between adjacent bracket pairs to form an arithmetic expression, then output its value.	Medium5	StackRecursion+1	No attempts yet	2s	1024 MB	Judgeable
Screamers in the StormGiven dimension D and radius R, compute the sum of absolute coordinate values over all integer points inside or on a centered sphere, modulo 1000000007.	Medium5	Dynamic programmingMath+1	No attempts yet	2s	1024 MB	Judgeable
Dinner for IntrovertsFind the most introverts that can sit at a round table of N seats so each one has at least K free chairs across its two neighboring gaps.	Medium5	MathGreedy	No attempts yet	0.5s	1024 MB	Judgeable
Bad BetsGiven a K-sided wheel spun N times, decide which of two target sums S1 or S2 is more likely to be the total of the spins.	Medium5	MathProbability	No attempts yet	0.5s	1024 MB	Judgeable
Monster MaskGiven a convex polygon, find the minimum width of the polygon, which is the shortest projection of all vertices onto a supporting line.	Medium5	GeometryTwo pointers	No attempts yet	1s	1024 MB	Judgeable
Greatest Greatest Common DivisorGiven L and R with R - L at most 10^6, find two distinct integers in [L, R] whose greatest common divisor is as large as possible.	Medium5	Number theoryBrute force+1	No attempts yet	1s	1024 MB	Judgeable
Margo Leaves MegabyteburgGiven a grid with walls, decide whether Margo can walk from the dormitory to the airport using single steps and at most K two-cell jumps.	Medium5	BFSGraph+1	No attempts yet	2s	1024 MB	Judgeable
Snakes&SnakesFind the fewest turns for a piece to reach cell N, where each roll of 6 grants another roll in the same turn and teleports pull the piece back.	Medium5	BFSShortest path+1	No attempts yet	1s	1024 MB	Judgeable
Divisibility TrickGiven d (1 to 1000), print a positive integer divisible by d whose digit sum is also divisible by d.	Medium5	MathNumber theory	No attempts yet	2s	1024 MB	Judgeable
Kitchen TimerSplit x into the fewest terms of the form 2^k - 1 (k at least 1) and output the number of terms minus one.	Medium5	GreedyMath+1	No attempts yet	2s	1024 MB	Judgeable
Weather TrendsGiven n daily temperatures and a window of m days, find the largest rise from an earlier day to a later day within that window.	Medium5	Sliding windowQueue+1	No attempts yet	20s	1024 MB	Judgeable
Huh? BannedChoose a subset of shout times so that no chosen shout falls in [t_i - b_i, t_i] of another chosen time, maximizing the sum of c_i.	Medium5	Dynamic programmingBinary search+1	No attempts yet	1s	1024 MB	Judgeable
Rush & SlashWeeds are grouped by 8-neighbor connectivity, and the task asks for the minimum total Manhattan travel to cut all of them, returning to the origin after each cut except the last.	Medium5	Union-findHash map+1	No attempts yet	2s	1024 MB	Judgeable
Doll ExhibitionGiven an R x C table and N doll heights, find the maximum number of dolls visible from the front when each column shows strictly increasing heights.	Medium5	Hash mapGreedy	No attempts yet	1s	1024 MB	Judgeable
Each to Their Own SquareFor each test case, count the squares whose four corners are all among the given n points, stopping when n is 0.	Medium5	Hash mapGeometry	No attempts yet	3s	1024 MB	Judgeable
Rush HourDecide whether roads from intersection 1 can carry p cars per second to all dead-end neighborhoods, given each road's capacity.	Medium5	GraphBFS	No attempts yet	0.5s	1024 MB	Judgeable
Drunkard's PathGiven bar qualities and distances, find the bar where Marcos is most likely to be after infinitely many moves, starting from bar b.	Medium5	ProbabilityMatrix+1	No attempts yet	0.5s	1024 MB	Judgeable
ArchipelagoPlace ships on water cells so every water cell is watched by a ship, and each numbered port has exactly that many ships directly north, south, east, or west of it.	Medium5	BacktrackingBrute force+1	No attempts yet	0.5s	1024 MB	Judgeable
Strange sumGiven a grid of colored cells, compute the sum of Manhattan distances over all pairs of cells that share a color.	Medium5	Hash mapSorting+1	No attempts yet	3s	1024 MB	Judgeable
Integral ArrayCheck whether floor(x/y) is in the array for every pair x >= y taken from the array, where all values are at most c.	Medium5	Prefix sumMath	No attempts yet	2s	1024 MB	Judgeable
Submitting AssignmentsGiven N knowledge pieces that each expire after a set number of days and M problems needing certain pieces, find the fewest studies needed to solve all problems in some order.	Medium5	Brute forceGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Cartel Nim GameThree players take turns removing 1 to K stones (A and B may take at most K/2 each), and the player taking the last stone wins; find which team wins.	Medium5	Game theoryDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Return of the Poop GameGiven a start power D and monster and equipment rooms, find the most rooms Gunho can clear before losing to a monster.	Medium5	GreedySorting	No attempts yet	0.5s	1024 MB	Judgeable
Coloring the FlagGiven two N by M letter grids A and B, decide whether A can be turned into B by repeatedly recoloring a same-color connected region to any other color.	Medium5	MatrixBFS+1	No attempts yet	1s	1024 MB	Judgeable
Up and DownOrder all cards in one sequence so each adjacent pair differs by exactly 1, or report -1 if no such order exists.	Medium5	ArrayMath+1	No attempts yet	1s	1024 MB	Judgeable
OlympiadGiven long-round scores, a cutoff place p, and the maximum short-round score, label each participant as always advancing, never advancing, or depending on the short round.	Medium5	Binary searchSorting	No attempts yet	2s	1024 MB	Judgeable
OlympiadGiven n, k, and x, find the smallest total difficulty of n non-negative integers such that removing any k of them leaves a sum of at least x.	Medium5	MathGreedy	No attempts yet	2s	1024 MB	Judgeable
MetroGiven n cards with balances a_i and p extra burles to distribute, find the maximum number of metro rides at fee k per ride.	Medium5	GreedySorting+1	No attempts yet	2s	1024 MB	Judgeable
Nested Candy BoxesGiven box counts a_i per nesting level, find the fewest boxes to open to collect at least x candies for each query.	Medium5	GreedySorting+2	No attempts yet	3s	1024 MB	Judgeable
Gleb and Two NumbersGiven two decimal integers l and r with up to 1000001 digits, find the largest Hamming distance between two numbers a and b with l <= a <= b <= r.	Medium5	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
Clean SocksGiven n socks with shades and a maximum allowed difference d, find the largest number of disjoint pairs whose shades differ by at most d.	Medium5	SortingGreedy	No attempts yet	2s	1024 MB	Judgeable
Keyboard and VirusGiven n symbol sets of size m, find the fewest key presses that always reveal which language the shuffled keyboard is using.	Medium5	Hash mapCombinatorics+1	No attempts yet	2s	1024 MB	Judgeable
DDRGiven N dance steps that each need one or two arrows pressed in order, find the minimum total Euclidean distance both feet travel.	Medium5	Dynamic programmingImplementation	No attempts yet	2s	1024 MB	Judgeable
Gahui and Sousenkyo 4Given the top vote count v and a gap k, pick the most distinct vote counts from 1 to v so that no two differ by exactly k.	Medium5	MathGreedy+1	No attempts yet	1s	512 MB	Judgeable
gahui and sousenkyo 6Given n and x, output n distinct positive integers below 2^63 whose bitwise XOR equals x.	Medium5	Bit manipulationMath+1	No attempts yet	1.5s	512 MB	Judgeable
Gahee and the TunnelCount the length-s strings over 7 snack colors that contain red, orange, yellow, green, blue, navy, purple in that order as a subsequence, modulo 998244353.	Medium5	Dynamic programmingCombinatorics+1	No attempts yet	1s	512 MB	Judgeable
Lexicographically Largest Common SubsequenceGiven two integer sequences A and B, find the lexicographically largest common subsequence and print its length and elements.	Medium5	Dynamic programmingArray	No attempts yet	1s	1024 MB	Judgeable
Sum of Intersection SizesGiven N sets, find for each k the sum of intersection sizes over all ways to pick k of the sets, modulo 998244353.	Medium5	CombinatoricsHash map	No attempts yet	4s	1024 MB	Judgeable
Geongong StringGiven a string S and a window length K, reverse each length-K window from left to right and print the final string.	Medium5	SimulationString+1	No attempts yet	1s	1024 MB	Judgeable
That Long NumberGiven k, find the k-th digit of the number formed by writing all positive palindromes in increasing order and joining them together.	Medium5	MathBinary search+1	No attempts yet	1s	1024 MB	Judgeable
Subsequence MEXGiven a positive integer n with up to 200000 digits, find the smallest positive integer whose digits cannot be picked in order from n's digits.	Medium5	Dynamic programmingString+1	No attempts yet	1s	1024 MB	Judgeable
Tourist PetrFind a simple path of at most 4 cities with the largest total enjoyment, given each city's value and the train routes between cities, and print the cities in visiting order.	Medium5	GraphBrute force+1	No attempts yet	2s	1024 MB	Judgeable
A Little Tale About a Purple BeaverGiven an array of integers with absolute value at most 2, find the contiguous subarray with the largest product and print its bounds.	Medium5	ArrayPrefix sum+1	No attempts yet	3s	1024 MB	Judgeable
Big Numbers for Little VasyaGiven a digit D repeated N and M times, print the GCD of the two numbers, or its last 10^6 digits if it is longer.	Medium5	MathNumber theory+1	No attempts yet	1s	1024 MB	Judgeable
Vasya and the ApartmentsGiven N apartments numbered 1 to N and a target sum S, find the fewest plates to swap for new natural numbers so the total becomes S.	Medium5	MathBinary search	No attempts yet	1s	1024 MB	Judgeable
Fruitful cooperationGiven N up to 10^16, count the closed regions formed in the digits when all numbers from 1 to N are written in a row.	Medium5	Dynamic programmingMath	No attempts yet	1s	1024 MB	Judgeable
Vasya and Cyclic ShiftsCount how many of a string's cyclic shifts equal its lexicographically smallest shift, for strings up to 10^7 characters long.	Medium5	StringString matching	No attempts yet	0.6s	1024 MB	Judgeable
A Million Scarlet RosesCount the distinct nonempty subsequences of a list of up to 1,000,000 bouquet sizes, modulo 1e9+7.	Medium5	Dynamic programmingArray+1	No attempts yet	1s	1024 MB	Judgeable
Odd NimGiven piles of stones where each move removes an odd number of stones, find the winner under normal and giving-up rules.	Medium5	Game theoryMath	No attempts yet	1s	1024 MB	Judgeable
ColonizationGiven N circles that must all touch each other externally, find the enclosed base area, or for N=3 the radius of a fourth circle that touches all three.	Medium5	GeometryMath	No attempts yet	1s	1024 MB	Judgeable
Reckless SpeleologistsFind the fastest route from the start station to the exit, reaching each station strictly before smoke spreading from the campfires does.	Medium5	GraphShortest path	No attempts yet	1s	1024 MB	Judgeable
XOR QueriesGiven an array with point updates, find the i-th largest value after XOR-ing every element with x, for each type 2 query.	Medium5	TrieBit manipulation	No attempts yet	2s	1024 MB	Judgeable
Too Many AssignmentsGiven a string and a number N, apply the wh-to-hw swap pass N times in a left-to-right sweep and print the result. Each pass swaps every adjacent "wh" pair.	Medium5	StringSimulation	No attempts yet	1s	1024 MB	Judgeable
Hanyang Popularity Exceeding CompetitionPick a subsequence of celebrities to meet in order, where each meeting adds 1 only if \|P-X\| is at most C. Find the maximum final popularity.	Medium5	Dynamic programmingArray	No attempts yet	1s	1024 MB	Judgeable
Meeting TimeGiven M, find the probability that three people arriving at uniform random times in a 60-minute window all overlap during their M-minute stays, as a reduced fraction.	Medium5	ProbabilityMath	No attempts yet	1s	1024 MB	Judgeable
Queries are not locksGiven a string with single-character updates, answer range queries for the number of subsequences equal to ROCK, modulo 1000000007.	Medium5	Segment treeDynamic programming+1	No attempts yet	2s	1024 MB	Judgeable
Escape the Ghost HouseFind the minimum time for Seokjun to walk from the entrance to the exit on a grid without entering the line of sight of any rotating ghost.	Medium5	BFSSimulation+1	No attempts yet	2s	1024 MB	Judgeable
Fixing FractionsGiven fractions a/b and c/d, decide whether removing the same digit positions from a and b can produce a fraction equal to c/d, and output the reduced pair if so.	Medium5	StringBrute force+1	No attempts yet	1s	1024 MB	Judgeable
Wiing WiingSort N points around Hyeok by the angle of a counterclockwise rotating ray from him, with nearer people first when two share a direction.	Medium5	SortingGeometry	No attempts yet	2s	1024 MB	Judgeable
A+B - 10 (Part 2)Find integers A and B from 1 to 10,000 using yes or no queries to the judge, then print A+B within 19,997 questions.	Medium5	Binary searchMath+1	No attempts yet	3s	1024 MB	Judgeable
FloodingGiven heights and queries (l, r, x), count the maximal runs of heights strictly above x that lie within positions l to r.	Medium5	ArraySorting+1	No attempts yet	2s	1024 MB	Judgeable
Group ProjectSplit N students with distinct IDs into pairs and one triple so that the sum of each team's max-min ID gap is minimized.	Medium5	SortingDynamic programming	No attempts yet	1s	512 MB	Judgeable
Minimum and MaximumGiven a sequence A, compute the XOR of the product of min and max over every non-empty subsequence of A.	Medium5	MathSorting+1	No attempts yet	1s	512 MB	Judgeable
SensorFor each query, count the integer points at squared distance w from the origin that lie in the clockwise sector between two given points.	Medium5	GeometryMath+1	No attempts yet	1s	512 MB	Judgeable
Super BusFind the shortest travel time from stop 1 to stop N, where a road can be used only when the sum of its two endpoints' disaster codes is prime.	Medium5	Shortest pathGraph+1	No attempts yet	1.5s	512 MB	Judgeable
A Slightly Slow but Kind FriendFind the shortest route that leaves the university, visits each neighborhood once, and returns, while each photo follows its ordering constraint.	Medium5	Dynamic programmingBit manipulation+1	No attempts yet	1s	512 MB	Judgeable
Avoid the bomb shot! Blue Padaengi!Given dog groups in a row of zones and Padaengi's start zone, decide whether Padaengi can walk within T seconds and collect exactly M dogs.	Medium5	Dynamic programmingIntervals+1	No attempts yet	1s	1024 MB	Judgeable
充成! Paran's DaengdaengiCount, for each building, the walks from building 1 that last exactly T minutes, where a three-building road lets you reach either other building in 2 minutes.	Medium5	MatrixDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable