Problems

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Total results29,326 problems

Ranking
Medium6
Combinatorics, Dynamic programming+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Check the String
Medium6
String, Simulation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Diophantine Equation
Medium6
Math, Number theory
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Jumping Path
Medium6
Sorting, Greedy+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Algebra
Medium6
Math, Number theory+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Replace Sort
Medium6
Greedy, Sorting+2
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Amazing Tree
Medium6
Tree, DFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Max Pair Matching
Medium6
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fence
Medium6
Math, Prefix sum+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Lemurs
Medium6
Prefix sum, Matrix+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Oops, It's Yesterday Twice More
Medium6
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Paimon Sorting
Medium6
Array, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Windblume Festival
Medium6
Math, Implementation
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Extravagant Experiment
Medium6
Simulation, BFS+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Unique lake
Medium6
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
King of Data Structures
Medium6
Union-find, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Mixed Integer Quadratic Programming
Medium6
Shortest path, Graph+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Cactus Folding Plus
Medium6
DFS, Graph+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Stargazing Trip
Medium6
Dynamic programming, Geometry
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
3+1 Tower of Hanoi
Medium6
Recursion, Divide and conquer+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Milano C.le
Medium6
Dynamic programming, Binary search
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Pretty numbers
Medium6
String, String matching+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Donation King's Nim Game
Medium6
Game theory, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
ICPC Team Generation
Medium6
Dynamic programming, Intervals
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Very Important Edge
Medium6
Minimum spanning tree, Graph+1
No attempts yet
Time limit
3s
Memory limit
2048 MB
Judgeable
Nanobugs
Medium6
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Potential
Medium6
Graph, BFS+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
What the Flex?
Medium6
Number theory, Greedy+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Pea-City
Medium6
Geometry, Divide and conquer
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Beautiful sums
Medium6
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Accounting Numeral System
Medium6
Combinatorics, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bipartite Graph
Medium6
Graph, Implementation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
List of Powers
Medium6
Math, Number theory+1
No attempts yet
Time limit
3.5s
Memory limit
1024 MB
Judgeable
Rotation Transformation
Medium6
Geometry, Matrix+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Gas Station
Medium6
Greedy, Stack+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Stationing
Medium6
Dynamic programming, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Master of Array Construction
Medium6
Dynamic programming, Combinatorics
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Python Code Folding
Medium6
Tree, Segment tree+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Dormitory Password Recovery
Medium6
Math, Matrix
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Junyeong
Medium6
Dynamic programming, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Pigtail Virus
Medium6
Tree, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Favourite Dish
Medium6
Geometry, Binary search+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Don't Copy the Manga
Medium6
Graph, Shortest path+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Balanced Tree Path
Medium6
Tree, DFS+2
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Magic Cube
Medium6
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Not Alone in 2024
Medium6
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rhythm Game of Balls
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Escaping the Mumummi Curse
Medium6
Geometry, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cowmpetency
Medium6
Array, Greedy+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Cannonball
Medium6
Simulation, Array
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Balancing Bacteria
Medium6
Greedy, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Move or Block!
Medium6
Game theory, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Guardian of the Forest
Medium6
Tree, DFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Palindrome Check
Medium6
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ants and Bitcoin
Medium6
Sorting, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Ethereum and Bitcoin
Medium6
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
LR Springboard
Medium6
Binary search, Divide and conquer+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Magic Square and Sudoku
Medium6
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Grill Below the Meats
Medium6
Implementation, Brute force
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Bulb Game
Medium6
Math, Greedy+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Alternative Mart
Medium6
Shortest path, Graph+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Personality Test
Medium6
Bit manipulation, String+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Room Temperature
Medium6
Binary search, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Construction Project 2
Medium6
Shortest path, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Gaji and the Wondrous Maze
Medium6
DFS, Tree+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Bessla Motors
Medium6
Shortest path, Graph+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Mirror Strings
Medium6
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Card Counting Club
Medium6
Heap, Simulation+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Rolete
Medium6
Sorting, Prefix sum+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Trokut
Medium6
Game theory, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Laser Trap
Medium6
Geometry, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Ants
Medium6
Prefix sum, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Assigned Seating 2
Medium6
Sorting, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hyundai Mobis Autonomous Driving Testing 2
Medium6
Matrix, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Twitch Plays Pokemon
Medium6
Dynamic programming, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Course Registration
Medium6
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Landscape Painting
Medium6
Dynamic programming, Matrix
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Covering an Interval
Medium6
Intervals, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Grand Escape
Medium6
Segment tree, Sorting+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
점호
Medium6
Queue, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Split the GSHS 3
Medium6
Tree, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
DiviDuelo
Medium6
Game theory, Number theory+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Joys of Trading
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Painting Fence Posts
Medium6
Prefix sum, Sorting+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Phoenix and Conquering the Earth
Medium6
Graph, Union-find+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Best Friends
Medium6
Geometry, Hash map+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Simple Problem
Medium6
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Classroom Assignment
Medium6
Dynamic programming, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rescue Squad
Medium6
Intervals, Sliding window+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Periodic Function (Hard)
Medium6
Prefix sum, String matching+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Magic Donut Game
Medium6
Segment tree, Array+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Closet
Medium6
Binary search, Dynamic programming+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Alphabet Queries (Hard)
Medium6
Segment tree, String
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Maze Escape
Medium6
Math, Greedy+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Traveling SCCC President 2
Medium6
Bit manipulation, Union-find+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Card Exchange
Medium6
Greedy, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
String Folding (Hard)
Medium6
String, Prefix sum+1
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Convenience Store Zone
Medium6
BFS, Matrix+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Lecture Rooms
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lulu and the Star Guardians
Medium6
Math, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
RankingGiven N contestants and K, count the distinct rank lists in which Geumseong finishes exactly K-th, with tied scores sharing a rank, modulo 1e9+7.	Medium6	CombinatoricsDynamic programming+1	No attempts yet	3s	1024 MB	Judgeable
Check the StringGiven a string s of a and b and a list of stack commands (copy, swap, roll, fuse), report CRASH if a command fails, otherwise whether the final top string equals s.	Medium6	StringSimulation+1	No attempts yet	2s	1024 MB	Judgeable
Diophantine EquationGiven n up to 10^9 (T up to 3000 queries), find positive integers x and y with x^3 + y^3 = n^2, or report that none exist.	Medium6	MathNumber theory	No attempts yet	1s	1024 MB	Judgeable
Jumping PathPopeye walks along a line with n forbidden zones and may jump over each zone with a pole of length R, so find the minimum time from A to B.	Medium6	SortingGreedy+2	No attempts yet	2s	1024 MB	Judgeable
AlgebraCount integer pairs (a, b) with \|a\|, \|b\| <= m such that x^n + a*x + b = 0 has exactly k distinct rational roots.	Medium6	MathNumber theory+1	No attempts yet	5s	1024 MB	Judgeable
Replace SortGiven an array A and a set B of distinct values, find the fewest elements of A to replace with values from B so that A becomes sorted, or report -1.	Medium6	GreedySorting+2	No attempts yet	3s	1024 MB	Judgeable
Amazing TreeGiven a tree, choose the starting vertex and neighbour order so the DFS post-order is lexicographically smallest, then print that order for each test case.	Medium6	TreeDFS+1	No attempts yet	1s	1024 MB	Judgeable
Max Pair MatchingGiven 2n pairs (a_i, b_i), find a perfect matching that maximizes the total of max(\|a_i-a_j\|, \|a_i-b_j\|, \|b_i-a_j\|, \|b_i-b_j\|) over matched pairs, and print that sum.	Medium6	GreedySorting	No attempts yet	1s	1024 MB	Judgeable
FenceFor each height b from 1 to M, compute the total length of the odd-numbered fence pieces when every plank is cut into pieces of length b.	Medium6	MathPrefix sum+1	No attempts yet	3s	1024 MB	Judgeable
LemursGiven an n by m grid of marked cells, decide whether some set of taxicab balls of radius k, each lying inside the grid, covers exactly the marked cells.	Medium6	Prefix sumMatrix+1	No attempts yet	4s	1024 MB	Judgeable
Oops, It's Yesterday Twice MoreGiven an n by n grid with one kangaroo per cell, output a U/D/L/R button sequence of length at most 3(n-1) that gathers all kangaroos at cell (a, b).	Medium6	ImplementationSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Paimon SortingFor each prefix of a sequence, count how many swaps the bubble-like Sort procedure performs on that prefix.	Medium6	ArraySorting+1	No attempts yet	1s	1024 MB	Judgeable
Windblume FestivalPlayers in a circle repeatedly remove a neighbor and subtract its value from the player before it, and the task is to find the maximum value the last player can hold.	Medium6	MathImplementation	No attempts yet	3s	1024 MB	Judgeable
Extravagant ExperimentGiven a grid of white and red cells and a sequence of k by k box moves, find the fewest rat steps consistent with the box movements.	Medium6	SimulationBFS+1	No attempts yet	3s	1024 MB	Judgeable
Unique lakeFind the length of the longest chain of points where each next point is strictly greater in both x and y, and count such longest chains modulo 1e9+7.	Medium6	Dynamic programmingSorting+1	No attempts yet	1s	1024 MB	Judgeable
King of Data StructuresRobots mow a grid by moving in one direction and removing grass as they go, and queries ask whether a cell has grass or how many cells still do.	Medium6	Union-findSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Mixed Integer Quadratic ProgrammingFind the max flow from vertex 1 to vertex n and its minimum cost, where each edge's cost is a x^2 + b x for flow x.	Medium6	Shortest pathGraph+1	No attempts yet	3s	1024 MB	Judgeable
Cactus Folding PlusDecide whether each edge length can match the distance between its endpoints on a line, and print vertex coordinates if it can.	Medium6	DFSGraph+1	No attempts yet	3s	1024 MB	Judgeable
Stargazing TripSplit M stars, kept in observation order, into N nonempty consecutive groups to maximize the sum of each group's Manhattan diameter.	Medium6	Dynamic programmingGeometry	No attempts yet	2s	1024 MB	Judgeable
3+1 Tower of HanoiMove N disks from peg A to peg D in a four-peg Hanoi game where disks on D cannot move, printing the minimum move count and one optimal sequence.	Medium6	RecursionDivide and conquer+1	No attempts yet	2s	1024 MB	Judgeable
Milano C.leGiven arrival and departure orders for n trains, find the fewest platforms so that no train is blocked by one that entered before it.	Medium6	Dynamic programmingBinary search	No attempts yet	1s	1024 MB	Judgeable
Pretty numbersGiven a sequence of N digits, find the largest pretty number formed by consecutive elements of the sequence.	Medium6	StringString matching+1	No attempts yet	1s	1024 MB	Judgeable
Donation King's Nim GameFor each three-pile Nim position, find how many stones each player takes when both play optimally, with the winner taking as many stones as possible.	Medium6	Game theoryDynamic programming	No attempts yet	1s	1024 MB	Judgeable
ICPC Team GenerationForm the most teams of three where each member's two teammates have ranks inside that member's [a, b] range, with a and b nondecreasing in rank.	Medium6	Dynamic programmingIntervals	No attempts yet	1s	1024 MB	Judgeable
Very Important EdgeGiven a weighted connected graph, find the edge whose removal gives the largest minimum spanning tree weight, and print that weight.	Medium6	Minimum spanning treeGraph+1	No attempts yet	3s	2048 MB	Judgeable
NanobugsGiven n bugs that are each a spy or an agent, output equal-size chamber checks that prove the spy count is a rather than b, or print -1 if that is impossible.	Medium6	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
PotentialFind integer vertex potentials that make every edge's reweighted value w + Φu - Φv equal, or report that no such potentials exist.	Medium6	GraphBFS+1	No attempts yet	3s	1024 MB	Judgeable
What the Flex?Given version a and limit N, find the next version after a that has the same set of prime divisors, or print -1 if none exists.	Medium6	Number theoryGreedy+1	No attempts yet	0.5s	1024 MB	Judgeable
Pea-CityGiven N points, find the minimum-area rectangle of any orientation that encloses all of them and print its four corners in counterclockwise order.	Medium6	GeometryDivide and conquer	No attempts yet	2s	1024 MB	Judgeable
Beautiful sumsGiven n, find the smallest integer with exactly n odd divisors (equivalently n beautiful sum representations), printed modulo 1000000009.	Medium6	Number theoryMath+1	No attempts yet	1s	1024 MB	Judgeable
Accounting Numeral SystemGiven n and m, find the unique strictly increasing indices x_1 to x_m such that n is the sum of C(x_i, i), printed from x_m down to x_1.	Medium6	CombinatoricsGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Bipartite GraphBuild a bipartite graph with d and d-2 vertices and at most 3d edges so that removing any two vertices from the first part still leaves a perfect matching.	Medium6	GraphImplementation+1	No attempts yet	2s	1024 MB	Judgeable
List of PowersGiven a prime p and a base a, list every integer in [l, r] that equals a^k mod p for some non-negative k, in ascending order.	Medium6	MathNumber theory+1	No attempts yet	3.5s	1024 MB	Judgeable
Rotation TransformationGiven a 3x3 rotation matrix, find the rotation angle in degrees and the unit axis vector that produce it.	Medium6	GeometryMatrix+1	No attempts yet	2s	1024 MB	Judgeable
Gas StationFind the minimum fuel cost to drive from the first gas station to position X, given each station's price, fuel stock, and the tank capacity F.	Medium6	GreedyStack+1	No attempts yet	1s	1024 MB	Judgeable
StationingPlace troops in regions to maximize the total number of neighboring regions without troops, where each region links to one other region d_i.	Medium6	Dynamic programmingGraph+1	No attempts yet	1s	1024 MB	Judgeable
Master of Array ConstructionCount the ways to replace each 0 in an array of length N with a value from 1 to N so that each value x appears at most x times, modulo 998244353.	Medium6	Dynamic programmingCombinatorics	No attempts yet	4s	1024 MB	Judgeable
Python Code FoldingGiven a correct Python code with indent levels, toggle folding of blocks by query and report how many lines remain visible after each print query.	Medium6	TreeSegment tree+1	No attempts yet	2s	1024 MB	Judgeable
Dormitory Password RecoveryRecover N hidden coefficients of a linear function mod 998244353 using at most N interactive queries, where every argument must be distinct.	Medium6	MathMatrix	No attempts yet	2s	1024 MB	Judgeable
JunyeongGiven an N by M chocolate bar, split it into rectangles with straight cuts to maximize the product of piece areas, modulo 1e9+7.	Medium6	Dynamic programmingMath	No attempts yet	1s	1024 MB	Judgeable
Pigtail VirusGiven a perfect binary tree of N cities and Q viruses that each add power p to cities within distance d of a source, print every city's total infection level.	Medium6	TreePrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
Favourite DishFor each weight pair, find the dish whose weighted sum of taste and plating scores is largest, breaking ties by the smallest dish number.	Medium6	GeometryBinary search+1	No attempts yet	4s	1024 MB	Judgeable
Don't Copy the MangaGiven a weighted multigraph, find the tree on Hanbyeol's route from B to C that Toka can reach fastest from A, breaking ties by smallest number.	Medium6	GraphShortest path+1	No attempts yet	1s	1024 MB	Judgeable
Balanced Tree PathCount the paths in a tree whose node labels, read in path order, form a balanced bracket string.	Medium6	TreeDFS+2	No attempts yet	2s	2048 MB	Judgeable
Magic CubeGiven an n by n by n cube of numbered small cubes and a list of slice rotations, report which cube ends up at each queried position.	Medium6	SimulationImplementation+1	No attempts yet	1s	2048 MB	Judgeable
Not Alone in 2024Given X = AC^2+BD^2 and Y = AB^2+CD^2 for segments AB and CD through the origin, output 2024 times MN^2 or -1 or -2.	Medium6	GeometryMath	No attempts yet	1s	1024 MB	Judgeable
Rhythm Game of BallsGiven N balls on a line that are stationary or moving left or right, find the total points scored from collisions until none occur.	Medium6	GreedySorting+1	No attempts yet	1s	1024 MB	Judgeable
Escaping the Mumummi CurseGiven lattice points inside two disjoint axis-aligned squares, find one point from each square that minimizes the squared distance between them.	Medium6	GeometrySorting	No attempts yet	1s	1024 MB	Judgeable
CowmpetencyFill the forgotten scores so the sequence is lexicographically smallest and each (a, h) pair makes cow h the first to beat cows 1 through a, or print -1.	Medium6	ArrayGreedy+1	No attempts yet	2s	1024 MB	Judgeable
CannonballGiven a number line of targets and jump pads, count how many targets Bessie breaks while bouncing from her starting cell.	Medium6	SimulationArray	No attempts yet	2s	1024 MB	Judgeable
Balancing BacteriaGiven N patches with signed bacteria offsets, find the fewest sprays from a linearly decaying sprayer anchored at patch N that bring every patch to zero.	Medium6	GreedyPrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
Move or Block!Given a line of N cells with walls and one piece, find the winner when players alternate moving the piece or placing a wall, with Mingyu first.	Medium6	Game theoryMath	No attempts yet	1s	1024 MB	Judgeable
Guardian of the ForestGiven a tree where fire starts at vertex a and Geunseong stands at vertex b, find the maximum number of vertices where he can copy data before the fire reaches him.	Medium6	TreeDFS+1	No attempts yet	1s	1024 MB	Judgeable
Palindrome CheckDecide whether a hidden sequence of length N is a palindrome using only count_pair and find_character queries under a limit on query sizes.	Medium6	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
Ants and BitcoinGiven N ants on a stick of length L, each facing left or right, print which ant holds the Bitcoin after T seconds.	Medium6	SortingMath+1	No attempts yet	1s	512 MB	Judgeable
Ethereum and BitcoinFind the dollar prices B and E of Bitcoin and Ethereum using at most 5 Exchange queries, each giving the BTC and ETH counts that exactly spend K dollars or -1 if impossible.	Medium6	MathNumber theory+1	No attempts yet	1s	512 MB	Judgeable
LR SpringboardDrop at most 16 balls on a row of N springs, reading only whether each ball exits left or right, so that every spring ends up facing left.	Medium6	Binary searchDivide and conquer+1	No attempts yet	1s	512 MB	Judgeable
Magic Square and SudokuConstruct a 16 by 16 Sudoku in which every 4 by 4 box is a magic square, and print any valid grid.	Medium6	MathImplementation+1	No attempts yet	1s	512 MB	Judgeable
Grill Below the MeatsTile a 40 by 40 grid with three identical unrotated pieces so that flipping any single piece leaves no valid position, and print one such layout.	Medium6	ImplementationBrute force	No attempts yet	1s	512 MB	Judgeable
Bulb GameSeonyul picks a button on each turn so that more bulbs are on than off once all N buttons have been pressed.	Medium6	MathGreedy+1	No attempts yet	1s	512 MB	Judgeable
Alternative MartFor each query, find the closest open discount mart from start region S, skipping up to 10 closed marts, and print its number and the shortest distance.	Medium6	Shortest pathGraph+1	No attempts yet	5s	512 MB	Judgeable
Personality TestFind a pair of students a < b who gave identical answers to at least k common questions, choosing the smallest b then the largest a, or report -1.	Medium6	Bit manipulationString+1	No attempts yet	3s	1024 MB	Judgeable
Room TemperatureChoose an integer room temperature that minimizes the worst officer's distance to their achievable temperatures A_i - kT, with k at least 0.	Medium6	Binary searchSorting+1	No attempts yet	2s	1024 MB	Judgeable
Construction Project 2Count station pairs (u, v) where a new L-minute line between them lets the King reach T from S within K minutes.	Medium6	Shortest pathSorting+1	No attempts yet	2s	1024 MB	Judgeable
Gaji and the Wondrous MazeFind every edge of a hidden tree by moving through it, where the judge picks each move among unvisited neighbors, using at most 4N moves.	Medium6	DFSTree+1	No attempts yet	0.5s	1024 MB	Judgeable
Bessla MotorsFind the travel destinations within R miles of at least K distinct charging stations on a weighted road graph, then print their count and list them in ascending order.	Medium6	Shortest pathGraph+1	No attempts yet	3s	1024 MB	Judgeable
Mirror StringsCount the mirror strings whose length is between L and R, where a mirror string looks the same flipped up-down or flipped left-right, modulo 10^9+7.	Medium6	Dynamic programmingCombinatorics+1	No attempts yet	1s	1024 MB	Judgeable
Card Counting ClubGiven N hands of cards and a penalty P per mark, print the order in which players run out of cards in the counting-out game.	Medium6	HeapSimulation+1	No attempts yet	8s	1024 MB	Judgeable
RoleteFor each h, find the minimum time to bring every blind down to at most h cm, mixing manual lifts (t per cm) with the parallel button (s per cm, slowed by k per finished blind).	Medium6	SortingPrefix sum+2	No attempts yet	2s	1024 MB	Judgeable
TrokutPlayers alternately add non-crossing segments between points of a regular N-gon, and whoever closes a triangle first wins. Report the winner for each N.	Medium6	Game theoryMath	No attempts yet	1s	1024 MB	Judgeable
Laser TrapFind the fewest generators to remove so that the origin lies outside the convex hull of the remaining points.	Medium6	GeometrySorting+1	No attempts yet	2s	1024 MB	Judgeable
AntsGiven n ants on a line, each facing left or right, count how many times each ant bounces off other ants when they collide and reverse.	Medium6	Prefix sumSimulation	No attempts yet	1s	1024 MB	Judgeable
Assigned Seating 2Count the ways to place each row's students in columns so that, within every column, height plus row offset strictly increases toward the back, modulo 10^9+7.	Medium6	SortingCombinatorics+1	No attempts yet	1s	1024 MB	Judgeable
Hyundai Mobis Autonomous Driving Testing 2Given sample 2-row tracks joined in order, find the minimum moves from the first column to the last using only road cells, or -1 if impossible.	Medium6	MatrixDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Twitch Plays PokemonGiven a maze and two command strings, interleave the two strings in any order that preserves each string's internal order to reach the exit in the fewest total commands.	Medium6	Dynamic programmingSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Course RegistrationGiven N courses with seat capacities a_i and interested-student counts b_i, find how many courses Dalgu can take under the best priority order against the worst registration order.	Medium6	GreedySorting	No attempts yet	1s	1024 MB	Judgeable
Landscape PaintingGiven an N by M grid of black and white cells, count the mountains and lakes of each size from 1 to N.	Medium6	Dynamic programmingMatrix	No attempts yet	1s	1024 MB	Judgeable
Covering an IntervalGiven N segments on a line, pick at most three that cover the interval from S to E, minimizing the total length of overlaps between the chosen pairs.	Medium6	IntervalsSorting+1	No attempts yet	2s	1024 MB	Judgeable
Grand EscapeEach resident falls straight down, and the fall slows by one step each time it touches a wall. Find the time each resident needs to reach y=0.	Medium6	Segment treeSorting+1	No attempts yet	3s	1024 MB	Judgeable
점호Each second, the frontmost first-year and second-year within the first K places leave the line. Find the time until all N students have left.	Medium6	QueueSimulation	No attempts yet	1s	1024 MB	Judgeable
Split the GSHS 3Given a tree of buildings with student counts, cut two edges to split it into three parts and maximize the product of their student totals.	Medium6	TreeDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
DiviDueloGiven N up to 10^12, decide whether the first player can force the gcd of their picked divisors to be greater than 1 under optimal play.	Medium6	Game theoryNumber theory+1	No attempts yet	1s	1024 MB	Judgeable
Joys of TradingSplit each resource's output between two villages, staying within each village's current person-hours, to minimize total person-hours.	Medium6	GreedySorting+1	No attempts yet	1s	1024 MB	Judgeable
Painting Fence PostsGiven a rectilinear fence loop and cow walks that take the shorter route, count how many times each post is touched.	Medium6	Prefix sumSorting+1	No attempts yet	3s	1024 MB	Judgeable
Phoenix and Conquering the EarthDecide whether grid A can be turned into grid B by repeatedly adding or subtracting 1 on both cells of a free domino, where volcano cells cannot be used.	Medium6	GraphUnion-find+1	No attempts yet	2s	1024 MB	Judgeable
Best FriendsProcess queries that toggle base stations on the plane and count the stations forming an acute triangle with (-x,0) and (x,0) for a given x.	Medium6	GeometryHash map+1	No attempts yet	2s	1024 MB	Judgeable
Simple ProblemGiven p and a sequence b, decide whether some permutation of 1 to N makes the maximum residue-class count over each prefix equal b_i.	Medium6	GreedyMath+1	No attempts yet	1s	1024 MB	Judgeable
Classroom AssignmentGiven N classrooms, pair them into floor(N/2) classes of two rooms each to find the maximum number of chocolate pies Jiwoong can receive.	Medium6	Dynamic programmingBit manipulation	No attempts yet	1s	1024 MB	Judgeable
Rescue SquadChoose a start hour s so that the window from s:30 to s+M:30 lets the most teams make two site visits, given each team's available hour intervals.	Medium6	IntervalsSliding window+1	No attempts yet	1s	1024 MB	Judgeable
Periodic Function (Hard)Given the integrals of a periodic function over each unit interval [i-1, i], print the integral over [a, b] using the function's period.	Medium6	Prefix sumString matching+1	No attempts yet	1s	1024 MB	Judgeable
Magic Donut GameGiven a circular board with rotate, flip, and range-add cards, output the sum of the first X cells from the reference cell for each sum card, modulo 1e9+7.	Medium6	Segment treeArray+1	No attempts yet	2s	512 MB	Judgeable
ClosetFind the smallest tolerance x so that removing at most M clothes leaves a sequence that rises then falls, with each adjacent step at most x.	Medium6	Binary searchDynamic programming+1	No attempts yet	5s	1024 MB	Judgeable
Alphabet Queries (Hard)For a string of uppercase letters, count maximal same-letter runs in a substring and shift the letters in a range forward by one, cyclically.	Medium6	Segment treeString	No attempts yet	2s	1024 MB	Judgeable
Maze EscapeGiven N rooms in a line, find the fewest teleports to room 1 or room N on a fastest walk from room S to room E.	Medium6	MathGreedy+1	No attempts yet	2s	1024 MB	Judgeable
Traveling SCCC President 2Find the path from building 1 to building N whose road lengths have the smallest bitwise OR, and print that OR value.	Medium6	Bit manipulationUnion-find+1	No attempts yet	3s	1024 MB	Judgeable
Card ExchangeGiven N card values with point values A_i and M turns of trading cards with a dealer, find the maximum score the player can end with.	Medium6	GreedyDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
String Folding (Hard)Given a string and many queries (l, r), find the maximum number of equal-letter pairs that touch when the substring S[l..r] is folded once between two adjacent characters.	Medium6	StringPrefix sum+1	No attempts yet	1.5s	1024 MB	Judgeable
Convenience Store ZoneGiven rooms with rents and stores on a grid, find the minimum of (Manhattan distance to the nearest store) times rent over all rooms.	Medium6	BFSMatrix+1	No attempts yet	3s	1024 MB	Judgeable
Lecture RoomsGiven N lecture room positions on a line and at most K teleports from x=0, find the minimum walking time to visit every room.	Medium6	GreedySorting+1	No attempts yet	1s	1024 MB	Judgeable
Lulu and the Star GuardiansSplit guardians numbered 1 to N into teams of K so that no team's power sum is divisible by K, or report NO if that is impossible.	Medium6	MathGreedy+1	No attempts yet	1s	1024 MB	Judgeable