Problems

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Total results29,416 problems

Adventurer on a Quest
Medium6
Hash map, Sorting+2
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Capsaicin Tastes Good in Spring
Medium6
Sorting, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
You on That Day
Medium6
Dynamic programming, DFS+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Sinkhole
Medium6
Math, Simulation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Junpyo's Pebbles
Medium6
Two pointers, Sliding window+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Eli's Curious Experiment
Medium6
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Super Ball
Medium6
Dynamic programming, Greedy
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Meeting
Medium6
Sliding window, Sorting+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Genetics
Medium6
String, Brute force+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Yule Lads
Medium6
Number theory, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Edge Coloring
Medium6
Math, Bit manipulation+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Ukje and Mysophobia
Medium6
Array, Sorting+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Pia Atelier: Alchemist of the Mystery Competition
Medium6
Brute force, Simulation+2
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Tree and Colors
Medium6
Tree, DFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Transformation move game
Medium6
Graph, BFS+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Pseudo-Banana Strings
Medium6
Dynamic programming, String+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Building a Spaceship
Medium6
Dynamic programming, Array+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
The Lion Is the King of Travel!!
Medium6
Binary search, Greedy+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Hyunwook Is the Parenthesis King!!
Medium6
Stack, String+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Thinking Heap
Medium6
Tree, Greedy+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Success
Medium6
BFS, Shortest path+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Two Robots
Medium6
Tree, DFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
XCorr
Medium6
Prefix sum, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
1, 2, 3 Sum 6
Medium6
Dynamic programming, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
1, 2, 3 Sum 8
Medium6
Dynamic programming, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Elevator 2
Medium6
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Home Coming
Medium6
Dynamic programming, Sliding window+1
No attempts yet
Time limit
0.3s
Memory limit
512 MB
Judgeable
Origami, or the Art of Folding Paper
Medium6
Simulation, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Skyscraper MinatoHarukas
Medium6
Math, Two pointers+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Recovery
Medium6
Greedy, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Water Testing
Medium6
Geometry, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Down the Pyramid
Medium6
Math, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Fighting Monsters
Medium6
Math, Number theory+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Jigsaw Puzzle
Medium6
Implementation, Hash map+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Mosaic Logic Puzzle
Medium6
Backtracking, DFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Bracket
Medium6
Dynamic programming, Combinatorics+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
The Total is Right
Medium6
Brute force, Recursion+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Lush Gears
Medium6
Dynamic programming, Array+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Commuting Mathematicians
Medium6
Graph, Shortest path+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Drawn and Quartered
Medium6
Math, Bit manipulation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Small Cube Lover
Medium6
Brute force, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Pythagorean
Medium6
Number theory, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
I am happy
Medium6
Segment tree, Math
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Subset Equal Partition
Medium6
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Course Registration
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Array and Gahui
Medium6
Hash map, Number theory+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Obstacle Running
Medium6
Graph, Shortest path+2
No attempts yet
Time limit
2.5s
Memory limit
256 MB
Judgeable
Club Cheer Volume
Medium6
Math, Number theory+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Subway in Seoul
Medium6
Graph, BFS+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Parade
Medium6
Graph, Union-find+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Noodle Team Contest
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Palapa Number
Medium6
Combinatorics, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Chinese ID Number
Medium6
String, Array+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
MST Game
Medium6
Minimum spanning tree, Graph+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Arm Wrestling
Medium6
Simulation, Greedy+1
No attempts yet
Time limit
1s
Memory limit
4 MB
Judgeable
Meetings
Medium6
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Mirror Cat Leaves a Mirror Behind When It Dies
Medium6
Simulation, Hash map+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Medicine Delivery
Medium6
Shortest path, Graph+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tree Investment
Medium6
Simulation, Implementation+2
No attempts yet
Time limit
0.3s
Memory limit
512 MB
Judgeable
Baby Shark
Medium6
BFS, Graph+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Moving Company
Medium6
Greedy, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Parallelepiped
Medium6
Hash map, Sorting+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Closing ceremony
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Cipher
Medium6
String, Simulation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Mortal Combat
Medium6
Greedy, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Set Theory
Medium6
Math, Combinatorics+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Lucid Strings
Medium6
String matching, Hash map+1
No attempts yet
Time limit
0.5s
Memory limit
512 MB
Judgeable
Daily Division
Medium6
Segment tree, Prefix sum+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Floating Points
Medium6
Geometry, Simulation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Jurassic Jigsaw
Medium6
Minimum spanning tree, Graph+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Birthday Boy
Medium6
Array, Sorting+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Financial Planning
Medium6
Greedy, Sorting+2
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Game Night
Medium6
String, Sliding window+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Memory Allocation
Medium6
Intervals, Simulation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Student Canteen
Medium6
Implementation, Linked list+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Well-Read
Medium6
Implementation, Recursion
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Circuits
Medium6
Sorting, Array+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Starwars
Medium6
Graph, BFS+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Prime Tree - 3
Medium6
Tree, Greedy+2
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Stoichiometry
Medium6
Math, Matrix+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Is-A? Has-A? Who Knowz-A?
Medium6
Graph, BFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Racing Around the Alphabet
Medium6
Math, Geometry+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Lost Map
Medium6
Tree, Graph+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Escape
Medium6
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Prime Currency
Medium6
Dynamic programming, Number theory+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cops and Robbers
Medium6
Graph, Shortest path+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Paper Strips
Medium6
String, Dynamic programming
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
To Tell the Truth
Medium6
Brute force, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Random Index Vectors
Medium6
Two pointers, Hash map+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Monkey Sports
Medium6
Combinatorics, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Piglets and Wolves
Medium6
Simulation, BFS+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Marbles
Medium6
Game theory, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Pizza Cutter
Medium6
Math, Combinatorics+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
The Chick's Transformation Is Not Guilty
Medium6
Dynamic programming, Matrix+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Boy Jump
Medium6
Graph, BFS+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
The Circumcenter and the Incenter Are Love
Medium6
Math, Geometry
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Horse Riding
Medium6
Geometry, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Triangle Hacker
Medium6
Math, Geometry
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Satisfaction Score
Medium6
Brute force, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Kaleidoscopic Palindromes
Medium6
Math, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Adventurer on a QuestMaintain a set of completed quest numbers under insertions and range queries asking how many integers in [L, R] are not yet completed.	Medium6	Hash mapSorting+2	No attempts yet	3s	256 MB	Judgeable
Capsaicin Tastes Good in SpringGiven N Scoville values, multiply each adjacent gap in sorted order by (2^k - 1) and sum modulo 1000000007.	Medium6	SortingCombinatorics+2	No attempts yet	1s	512 MB	Judgeable
You on That DayGiven measured environmental factors and one-operation definitions, compute each factor's partial derivative of HAPPY and print it as a reduced fraction.	Medium6	Dynamic programmingDFS+2	No attempts yet	1s	512 MB	Judgeable
SinkholeA stone bounces between the walls of a hole with its horizontal speed dropping to 80% on each wall hit and its vertical fall restarting; count wall hits before it reaches depth D.	Medium6	MathSimulation+1	No attempts yet	1s	512 MB	Judgeable
Junpyo's PebblesFind the longest contiguous segment containing at most B black pebbles and at least W white pebbles.	Medium6	Two pointersSliding window+1	No attempts yet	1s	512 MB	Judgeable
Eli's Curious ExperimentCount the maximal independent sets of a path on N vertices that have size at least two, for many N up to 76, labeled by test case number.	Medium6	Dynamic programmingCombinatorics+1	No attempts yet	3s	512 MB	Judgeable
Super BallChoose a factory for each layer in the production order and again in the recycling order, minimizing layer costs plus transfer costs C whenever consecutive layers use different factories.	Medium6	Dynamic programmingGreedy	No attempts yet	2s	512 MB	Judgeable
MeetingAdjust arrival times at cost 1 per second so that exactly K subordinates sit in an interval [0, X] with X a nonnegative integer; minimize cost.	Medium6	Sliding windowSorting+2	No attempts yet	2s	512 MB	Judgeable
GeneticsGiven N DNA strings of length M, find the one string that differs from every other string in exactly K positions.	Medium6	StringBrute force+2	No attempts yet	2s	1024 MB	Judgeable
Yule LadsSome Yule Lads skip their night; each remaining visitor K toggles every house whose number is a multiple of K, and exactly one set of absent Lads leaves all houses except house 1 lit. Count who came.	Medium6	Number theoryMath+2	No attempts yet	1s	1024 MB	Judgeable
Edge ColoringCount subsets of edges of a multigraph, modulo 100000007, such that every vertex has an odd number of chosen incident edges.	Medium6	MathBit manipulation+2	No attempts yet	2s	256 MB	Judgeable
Ukje and MysophobiaSort a permutation of 1 to N by repeatedly reversing intervals, using at most N*N reversals to make card i sit at position i.	Medium6	ArraySorting+2	No attempts yet	2s	256 MB	Judgeable
Pia Atelier: Alchemist of the Mystery CompetitionChoose and order 3 of up to 10 candidate 4x4 materials, placing each rotated onto a 5x5 furnace, to maximize a weighted color-sum quality.	Medium6	Brute forceSimulation+2	No attempts yet	3s	512 MB	Judgeable
Tree and ColorsGiven a rooted tree with colored vertices and queries f(v,c) counting subtree vertices of color at most c, print the sum of all answers modulo 1e9+7.	Medium6	TreeDFS+2	No attempts yet	2s	512 MB	Judgeable
Transformation move gameFind the fewest turns to reach a target cell on an N by N board where you can walk one cell per turn in normal mode or, after paying t turns, warp to the nearest warp cell in a direction.	Medium6	GraphBFS+1	No attempts yet	2s	512 MB	Judgeable
Pseudo-Banana StringsGiven a string of B, A, N, find the minimum number of character replacements that turn it into a concatenation of blocks of the form B+ANANA(NA)*.	Medium6	Dynamic programmingString+2	No attempts yet	2s	512 MB	Judgeable
Building a SpaceshipPartition the ordered parts into contiguous groups, paying for each group the product of its maximum weight and maximum energy; minimize the total cost.	Medium6	Dynamic programmingArray+2	No attempts yet	2s	512 MB	Judgeable
The Lion Is the King of Travel!!Given N days and M fixed non-overlapping-or-not travel intervals, choose a subset of disjoint intervals minimizing the longest gap of untraveled days.	Medium6	Binary searchGreedy+2	No attempts yet	2s	512 MB	Judgeable
Hyunwook Is the Parenthesis King!!Given a string of parentheses, find the length of the longest contiguous substring that forms a correct parenthesis string.	Medium6	StackString+2	No attempts yet	2s	512 MB	Judgeable
Thinking HeapGiven N, k, and p, the task is to find an insertion order of 1 to N into an empty binary min-heap that places k at array index p, or print -1 if none exists.	Medium6	TreeGreedy+1	No attempts yet	1s	512 MB	Judgeable
SuccessFind the fewest D by D blasts needed to clear obstacles so a path of open cells exists from the top-left to the bottom-right of an N by M grid.	Medium6	BFSShortest path+1	No attempts yet	2s	512 MB	Judgeable
Two RobotsOn a weighted tree, two robots at given nodes must meet on some edge or its endpoints; find the minimum combined distance traveled.	Medium6	TreeDFS+2	No attempts yet	2s	512 MB	Judgeable
XCorrGiven two sparse nonnegative sequences, sum the cross-correlation XCorr(t) over all shifts t in a query range.	Medium6	Prefix sumMath+2	No attempts yet	2s	512 MB	Judgeable
1, 2, 3 Sum 6Count the compositions of n into parts 1, 2, and 3 that read the same forwards and backwards, modulo 1,000,000,009.	Medium6	Dynamic programmingCombinatorics+2	No attempts yet	1s	512 MB	Judgeable
1, 2, 3 Sum 8For each n, count the ordered compositions of n into parts 1, 2, 3, reporting the number using an odd count of terms and the number using an even count, each modulo 1,000,000,009.	Medium6	Dynamic programmingMath+1	No attempts yet	1s	512 MB	Judgeable
Elevator 2Each elevator i stops on floors Xi, Xi+Yi, Xi+2Yi, ... Find the fewest elevator rides to travel from floor A to floor B and output one such sequence.	Medium6	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
Home ComingOn a circle of N textbooks, pick subjects so that the prize sum minus the cost of all textbooks needed to pass them is as large as possible.	Medium6	Dynamic programmingSliding window+1	No attempts yet	0.3s	512 MB	Judgeable
Origami, or the Art of Folding PaperFold a rectangle several times along axis-aligned lines, punch holes in the folded stack, and count how many holes each punch makes in the unfolded sheet.	Medium6	SimulationImplementation+2	No attempts yet	2s	512 MB	Judgeable
Skyscraper MinatoHarukasFor each budget b, find the longest run of consecutive positive integers summing to b and print its first floor and length.	Medium6	MathTwo pointers+2	No attempts yet	2s	512 MB	Judgeable
RecoveryGiven row and column parities of a lost 0/1 matrix, output the matrix with the most ones, and among those the lexicographically smallest row-major string, or -1 if none exists.	Medium6	GreedyImplementation+2	No attempts yet	2s	512 MB	Judgeable
Water TestingGiven the corner points of a simple polygon in order, count the integer lattice points that lie strictly inside it.	Medium6	GeometryMath+2	No attempts yet	2s	512 MB	Judgeable
Down the PyramidCount non-negative integer sequences of length n+1 lying under a given length-n sequence, where each adjacent pair sums to the number above it.	Medium6	MathImplementation+2	No attempts yet	2s	512 MB	Judgeable
Fighting MonstersFind two monsters whose fight to the death leaves the survivor with exactly power 1, and report the starting index and the other index, or impossible.	Medium6	MathNumber theory+2	No attempts yet	2s	512 MB	Judgeable
Jigsaw PuzzleAssemble n jigsaw pieces, rotation allowed but not flipping, so matching irregular edges meet and straight edges form the border of an h by w rectangle, or report impossible.	Medium6	ImplementationHash map+1	No attempts yet	2s	512 MB	Judgeable
Mosaic Logic PuzzleGiven clue numbers on a border-extended grid saying how many of the 3x3 neighbors are black, color cells black or report impossibility.	Medium6	BacktrackingDFS+2	No attempts yet	2s	512 MB	Judgeable
BracketGiven a bracket pattern with some fixed brackets and some dots, count the ways to fill the dots so the whole string is a balanced bracket sequence.	Medium6	Dynamic programmingCombinatorics+2	No attempts yet	2s	512 MB	Judgeable
The Total is RightDecide whether a target N can be formed exactly from up to six given integers using +, -, times, and exact division with positive intermediates.	Medium6	Brute forceRecursion+2	No attempts yet	2s	512 MB	Judgeable
Lush GearsPick one model per gear type so the total cost is as close to C as possible without exceeding it, and report the leftover coins.	Medium6	Dynamic programmingArray+1	No attempts yet	2s	512 MB	Judgeable
Commuting MathematiciansGiven a subway network of lines with travel times, find a route from F to D that minimizes total time, then minimizes line transfers among fastest routes.	Medium6	GraphShortest path+2	No attempts yet	2s	512 MB	Judgeable
Drawn and QuarteredA fixed permutation is applied to a string K times; find where each index goes and output the rearranged string.	Medium6	MathBit manipulation+1	No attempts yet	2s	512 MB	Judgeable
Small Cube LoverGiven eight corner pieces with three colored stickers each, decide whether they can be oriented and placed to form a 2x2x2 cube with each face a single color.	Medium6	Brute forceImplementation+1	No attempts yet	1s	512 MB	Judgeable
PythagoreanCount pairs (m, n) with n < m <= L whose Euclidean generation yields a primitive Pythagorean triple.	Medium6	Number theoryMath+2	No attempts yet	2s	512 MB	Judgeable
I am happyGiven a digit string, apply range digit replacements and answer range queries for the number modulo 998244353.	Medium6	Segment treeMath	No attempts yet	3s	512 MB	Judgeable
Subset Equal PartitionCount the ways to split the set {1,...,N} into two subsets with equal sums, or print 0 if no split exists.	Medium6	Dynamic programmingCombinatorics+1	No attempts yet	1s	256 MB	Judgeable
Course RegistrationChoose courses so total credits fall between n_lo and n_hi, maximizing the sum of their happiness scores, with each course credit at most 5.	Medium6	GreedySorting+1	No attempts yet	2s	256 MB	Judgeable
Array and GahuiProcess point updates on an array and after each one count index pairs whose two values have GCD greater than one.	Medium6	Hash mapNumber theory+2	No attempts yet	2s	512 MB	Judgeable
Obstacle RunningAssign K shortest paths from each row's start in column 1 to the cheapest reachable cell in column M, and count how many students land on each finish cell.	Medium6	GraphShortest path+2	No attempts yet	2.5s	256 MB	Judgeable
Club Cheer VolumeGiven N ideal volumes, find the smallest shout volume D so that at least K members reach satisfaction at least X percent, and print D as an integer or reduced fraction.	Medium6	MathNumber theory+2	No attempts yet	1s	256 MB	Judgeable
Subway in SeoulGiven up to 10 subway lines, each listing stations (0 is the start), find the minimum number of transfers to reach a destination station.	Medium6	GraphBFS+2	No attempts yet	2s	128 MB	Judgeable
ParadeGiven an undirected graph with V vertices and E edges, decide whether it has an Eulerian circuit that traverses every edge exactly once.	Medium6	GraphUnion-find+2	No attempts yet	2s	128 MB	Judgeable
Noodle Team ContestGiven each member's pot time and seasoning time, order the members to minimize the total time until all noodles are finished.	Medium6	GreedySorting+1	No attempts yet	2s	512 MB	Judgeable
Palapa NumberCount N-digit numbers (no leading zero) where the first two digits sum to an even value or the last two digits form a prime, modulo 9973.	Medium6	CombinatoricsMath+2	No attempts yet	2s	512 MB	Judgeable
Chinese ID NumberCheck an 18-character Chinese ID: region code from a given list, birthday in 1900 to 2011, sequence code not 000, then for valid IDs report gender by odd/even sequence code. The checksum is a mod 11 weighted sum of the first 17 digits plus a digit x making the total 1, with x=10 written as 'X'.	Medium6	StringArray+2	No attempts yet	2s	512 MB	Judgeable
MST GameGiven an edge-weighted simple graph and a turn count K, find the MST cost each turn and delete the lightest MST edge after each turn, outputting 0 once the graph has no spanning tree.	Medium6	Minimum spanning treeGraph+2	No attempts yet	2s	512 MB	Judgeable
Arm WrestlingGiven N rounds of strengths for two players, decide the winner using a one-time 1.5x boost with next-round penalty, ending when a cumulative total hits K or one side leads by 50.	Medium6	SimulationGreedy+1	No attempts yet	1s	4 MB	Judgeable
MeetingsEach person occupies an interval [Si, Ei]; pair up people whose intervals overlap into disjoint pairs and maximize the number of pairs.	Medium6	GreedySorting+2	No attempts yet	1s	1024 MB	Judgeable
The Mirror Cat Leaves a Mirror Behind When It DiesGiven N cats in fire order, each living cat emits beams in four directions blocked by any mirror; a cat dies if hit, leaving a mirror below its cell; count survivors.	Medium6	SimulationHash map+2	No attempts yet	1s	1024 MB	Judgeable
Medicine DeliveryFind the fastest route from one settlement to the other along roads, pausing 5 minutes at equipment stations to wash whenever 100 minutes of driving would otherwise be exceeded.	Medium6	Shortest pathGraph+2	No attempts yet	1s	1024 MB	Judgeable
Tree InvestmentTrack trees by age on each cell of an N by N grid and run spring to winter nutrient cycles for K years to count survivors.	Medium6	SimulationImplementation+2	No attempts yet	0.3s	512 MB	Judgeable
Baby SharkOn a grid with fish and a baby shark that eats smaller fish and grows, simulate its BFS-driven meal choices and report the total time spent.	Medium6	BFSGraph+2	No attempts yet	2s	512 MB	Judgeable
Moving CompanyGiven counts of items weighing 1 to 5 kg, find the minimum number of 5 kg baskets needed to pack them all.	Medium6	GreedyMath+2	No attempts yet	2s	512 MB	Judgeable
ParallelepipedGiven n rectangular sheets, pick 6 to form the faces of a rectangular box (opposite faces must match in size), maximizing the volume. Output -1 if impossible.	Medium6	Hash mapSorting+2	No attempts yet	2s	512 MB	Judgeable
Closing ceremonyAssign every seat to a person from two entrances at (0,0) and (0,m+1), matching stamina limits to the walk distance, and say if a perfect assignment exists.	Medium6	GreedySorting+1	No attempts yet	5s	512 MB	Judgeable
CipherGiven a per-position code table and an encoded counter that increases each second, find the fewest seconds until the display reveals the starting number.	Medium6	StringSimulation+1	No attempts yet	2s	512 MB	Judgeable
Mortal CombatSend heroes one at a time to kill the boss, choosing the order that loses the fewest heroes, or report -1 if the boss wins.	Medium6	GreedyMath+2	No attempts yet	2s	512 MB	Judgeable
Set TheoryGiven a set A of n integers, find a set B of n distinct integers in [1, 10^6] so that all n^2 sums a_i + b_j are distinct, or report that none exists.	Medium6	MathCombinatorics+2	No attempts yet	2s	512 MB	Judgeable
Lucid StringsCount the substrings of a string of length n that split into k equal-length pieces where all k pieces are pairwise distinct.	Medium6	String matchingHash map+1	No attempts yet	0.5s	512 MB	Judgeable
Daily DivisionAfter each change to one hut's guest count, report the hut where the food truck should park to make the left and right queues as balanced as possible.	Medium6	Segment treePrefix sum+1	No attempts yet	5s	512 MB	Judgeable
Floating PointsGiven a simple polygon ship and x-coordinates where balls are released far below it, count the balls that get trapped under the hull and push it up.	Medium6	GeometrySimulation	No attempts yet	1s	512 MB	Judgeable
Jurassic JigsawGiven n DNA strings of length k, build a spanning tree minimizing the total Hamming distance over its edges, and print the cost plus the edges.	Medium6	Minimum spanning treeGraph+2	No attempts yet	1s	512 MB	Judgeable
Birthday BoyGiven colleagues' birthdays on a non-leap calendar, pick a date not used by anyone that maximizes the gap just before it, breaking ties toward the earliest date after October 27.	Medium6	ArraySorting+2	No attempts yet	1s	512 MB	Judgeable
Financial PlanningGiven investments with cost and daily profit, find 0 or more to buy after borrowing, minimizing days d until total profit times d exceeds total cost plus M.	Medium6	GreedySorting+2	No attempts yet	3s	512 MB	Judgeable
Game NightGiven a circular arrangement of A, B, and C seats, find the minimum people to move so each team forms one contiguous block.	Medium6	StringSliding window+2	No attempts yet	1s	512 MB	Judgeable
Memory AllocationSimulate first-fit malloc and free over 100,000 memory cells and print requested variable values in command order.	Medium6	IntervalsSimulation+2	No attempts yet	1s	512 MB	Judgeable
Student CanteenStudents numbered by arrival either join the back of a queue or cut in right ahead of an earlier student; report each cutter's 1-indexed position at that moment.	Medium6	ImplementationLinked list+1	No attempts yet	1s	512 MB	Judgeable
Well-ReadGiven n students who each hold a different book, output at most 4950 pairwise swaps so that every student eventually holds every book.	Medium6	ImplementationRecursion	No attempts yet	2s	512 MB	Judgeable
CircuitsGiven axis-aligned rectangles, choose two horizontal lines to maximize how many distinct rectangles they touch along a top or bottom side.	Medium6	SortingArray+2	No attempts yet	2s	512 MB	Judgeable
StarwarsGiven human systems, bases, and directed labeled wormholes, decide whether a nonhuman start yields a certificate sequence matching one produced by some human start reaching any base.	Medium6	GraphBFS+2	No attempts yet	1s	512 MB	Judgeable
Prime Tree - 3Relabel a tree's vertices with 1 to n to minimize edges whose endpoints share a prime factor, and output the labeling for every test case.	Medium6	TreeGreedy+2	No attempts yet	10s	512 MB	Judgeable
StoichiometryBalance each equation line's element counts by solving the homogeneous linear system over elements, then output integer coefficients scaled to their smallest coprime form.	Medium6	MathMatrix+1	No attempts yet	2s	512 MB	Judgeable
Is-A? Has-A? Who Knowz-A?Given is-a and has-a edges between classes, answer queries whether one class is-a or has-a another using inheritance and field transitivity.	Medium6	GraphBFS+2	No attempts yet	2s	512 MB	Judgeable
Racing Around the AlphabetCompute the running time for a player who follows a message's characters around 28 marks on a circle, using the shortest arc between marks and 1 second per pickup.	Medium6	MathGeometry+2	No attempts yet	2s	512 MB	Judgeable
Lost MapGiven an all-pairs distance table of an unknown tree with n up to 2500, recover the tree by its n-1 edges.	Medium6	TreeGraph+1	No attempts yet	5s	512 MB	Judgeable
EscapeFind the fewest presses of A (add 1) and B (double then cut the leading digit) turning N into G without passing 99999 in T steps, or report impossible.	Medium6	BFSGraph+1	No attempts yet	1s	256 MB	Judgeable
Prime CurrencyCount the unordered ways to make N with unlimited primes, using a coin-change DP, and print the count modulo 123,456,789.	Medium6	Dynamic programmingNumber theory+1	No attempts yet	1s	256 MB	Judgeable
Cops and RobbersBlock the robbers' escape from the bank at minimum cost by barricading priced terrain cells, treating it as a minimum vertex cut on the grid graph.	Medium6	GraphShortest path+2	No attempts yet	5s	512 MB	Judgeable
Paper StripsGiven a lowercase string, find the fewest cuts needed so that the cut pieces can be rearranged into a bitonic string.	Medium6	StringDynamic programming	No attempts yet	2s	512 MB	Judgeable
To Tell the TruthGiven n people each claiming the true count lies in [a,b], find the largest consistent truth-teller count or -1 if none exists.	Medium6	Brute forceMath+1	No attempts yet	2s	512 MB	Judgeable
Random Index VectorsMerge two sparse signed index lists to output their element-wise sum, product, and each list rotated left by k with wraparound.	Medium6	Two pointersHash map+2	No attempts yet	2s	512 MB	Judgeable
Monkey SportsAssign each of N monkeys to team A or B on each of 7 days so that every pair of monkeys is split across teams on at least one day.	Medium6	CombinatoricsMath+2	No attempts yet	1s	128 MB	Judgeable
Piglets and WolvesGiven an N by M grid with grassland, ice, mountains and wolf starts, simulate wolf sliding on ice and mark unreachable grassland cells as P.	Medium6	SimulationBFS+2	No attempts yet	1s	256 MB	Judgeable
MarblesTreat marbles as Wythoff/Nim heap coordinates and compute Sprague-Grundy values to decide if the first player wins.	Medium6	Game theoryMath+2	No attempts yet	2s	512 MB	Judgeable
Pizza CutterCount the pieces made by H rightward and V upward cuts whose endpoints are given, using Euler's formula and inversion counting of crossing pairs.	Medium6	MathCombinatorics+2	No attempts yet	2s	512 MB	Judgeable
The Chick's Transformation Is Not GuiltyEach chick lays one egg daily and each egg hatches K days later. Find the chick count after N days modulo 100000007.	Medium6	Dynamic programmingMatrix+1	No attempts yet	1s	512 MB	Judgeable
Boy JumpGiven a grid maze and three start cells, find the meeting cell minimizing the maximum shortest-path distance from the three starts, and count all optimal cells or report -1 if unreachable.	Medium6	GraphBFS+2	No attempts yet	1s	512 MB	Judgeable
The Circumcenter and the Incenter Are LoveGiven circumradius R and inradius r, output the floor of the squared distance between a triangle's circumcenter and incenter using Euler's formula R^2 - 2Rr.	Medium6	MathGeometry	No attempts yet	1s	512 MB	Judgeable
Horse RidingPlace the square's corners at (0,0), (b,0), (0,b), (b,b), compute A's coordinates from its distances to two adjacent corners, then output the squared distance to the point m along the side between them.	Medium6	GeometryMath+1	No attempts yet	1s	512 MB	Judgeable
Triangle HackerGiven the three side lengths of an acute triangle, compute its area, circumradius, inradius, circumcenter-incenter distance, and the sum of the circumcenter's perpendicular distances to the sides.	Medium6	MathGeometry	No attempts yet	1s	512 MB	Judgeable
Satisfaction ScoreSplit 8 skill scores into two doubles games and re-pair each game's four players into teams to maximize the minimum satisfaction over all members.	Medium6	Brute forceImplementation+1	No attempts yet	2s	512 MB	Judgeable
Kaleidoscopic PalindromesCount numbers in [a, b] that read as palindromes in every base from 2 through k.	Medium6	MathImplementation+2	No attempts yet	2s	512 MB	Judgeable