Problems

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Total results29,054 problems

Blood groups
Medium7
Graph, Combinatorics
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Cake cut
Medium7
Geometry, Game theory+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Exposing corruption
Medium7
Dynamic programming, Graph+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Galactic Taxes
Medium7
Shortest path, Binary search
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Height Map
Medium7
BFS, Sorting+2
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Keep it energized
Medium7
Dynamic programming, Segment tree+2
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Pyramid Base 2
Medium7
Binary search, Segment tree+1
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
CLARKSON
Medium7
String matching, Binary search+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Traffic Lights
Medium7
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Stepping Stones on Ingyeong Lake
Medium7
Dynamic programming, Graph+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
ARTUR
Medium7
Topological sort, Geometry+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Airports
Medium7
Graph, Shortest path
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Falling Blocks
Medium7
Graph, DFS+2
No attempts yet
Time limit
4s
Memory limit
256 MB
Judgeable
Racing Gems
Medium7
Dynamic programming, Sorting+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Coverage
Medium7
Geometry, Union-find+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Digit Division
Medium7
Dynamic programming, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Ice Igloos
Medium7
Geometry, Matrix
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Godzilla
Medium7
BFS, Simulation+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Hotels
Medium7
Shortest path, Graph+2
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Mario
Medium7
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Amazing Race
Medium7
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Productivity improvement
Medium7
Dynamic programming, Sorting+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Debugging
Medium7
Dynamic programming, Binary search
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Elementary Math
Medium7
Graph, Greedy
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Promotions
Medium7
Topological sort, Graph
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Landscaping
Medium7
Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Game of Cards
Medium7
Game theory, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
LCM(i, j)
Medium7
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Sigma Function
Medium7
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Nim Game
Medium7
Game theory
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Table Game
Medium7
Game theory, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
AYBABTU
Medium7
Dynamic programming, Tree
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Billiards Sorting
Medium7
BFS, Graph+1
No attempts yet
Time limit
7s
Memory limit
512 MB
Judgeable
Longest Lane
Medium7
Geometry, Brute force
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
PLAY in BASIC
Medium7
Dynamic programming, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Three-way Branch
Medium7
Dynamic programming, Matrix
No attempts yet
Time limit
7s
Memory limit
64 MB
Judgeable
JAG-channel II
Medium7
Backtracking, Simulation+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
New Game AI
Medium7
Sorting, Graph+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Sprinkler layout
Medium7
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Watering
Medium7
Backtracking, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Binary vs Decimal
Medium7
Number theory, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Froggy Ford
Medium7
Binary search, Geometry+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Iceberg Orders
Medium7
Simulation, Heap+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
The Brothers Game
Medium7
Game theory, Graph+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Bringing Order to Disorder
Medium7
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Alpaca Sentence
Medium7
Dynamic programming, String+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Being Solarly Systematic
Medium7
Simulation, Number theory+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Delete This!
Medium7
Geometry, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Transportation Delegation
Medium7
Graph
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Trick Shot
Medium7
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Shortest Complete Subarray
Medium7
Segment tree, Sliding window+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Namuk's Rotten Egg Tray
Medium7
Backtracking, Sorting+1
No attempts yet
Time limit
4s
Memory limit
512 MB
Judgeable
Fibonacci numbers and their greatest common divisor
Medium7
Number theory, Matrix+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Rush Hour
Medium7
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Terrorists
Medium7
Shortest path, Tree
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Aquarium
Medium7
Minimum spanning tree, Union-find+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Jumping Joey
Medium7
Dynamic programming, Greedy+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Primorial vs LCM
Medium7
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Building a Scholarship Table
Medium7
Brute force, Math+1
No attempts yet
Time limit
4s
Memory limit
256 MB
Judgeable
Tom and Jerry
Medium7
Math, Geometry
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
The Three-Way Splitting Weapon
Medium7
Geometry, Math
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Performance Assessment 2
Medium7
Dynamic programming, Greedy+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Wedding Selfie
Medium7
Geometry, Math+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Mario and the Evil Toad
Medium7
Dynamic programming, Tree+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Boring Planet Pairs
Medium7
Union-find, Hash map
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Endor Chameleons
Medium7
Simulation, Sorting
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Symmetry
Medium7
Geometry, Hash map+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Watermelons of the Field of Wonders
Medium7
Segment tree, Sorting+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Martian King
Medium7
Dynamic programming, Binary search+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Cache
Medium7
Dynamic programming, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Energetic turtle
Medium7
Combinatorics, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Weighing the stones
Medium7
Segment tree, Greedy+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
K-th path
Medium7
Greedy, Dynamic programming
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Beautiful row
Medium7
Dynamic programming, Graph+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
XOR
Medium7
Trie, Bit manipulation+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Biochips
Medium7
Dynamic programming, Tree
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Monkey and Apple Trees
Medium7
Segment tree, Intervals
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Luxury burrow
Medium7
Binary search, Stack+1
No attempts yet
Time limit
2s
Memory limit
64 MB
Judgeable
Gold Camp Forcefield
Medium7
Segment tree, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
K blocks
Medium7
Dynamic programming, Stack+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Area covered by squares
Medium7
Geometry, Combinatorics
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Odd Even Nim
Medium7
Game theory, Math
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
OOP
Medium7
String matching, Hash map+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Filling in the Brackets
Medium7
Greedy, Heap
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Polygon
Medium7
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Min-cost GCD
Medium7
Greedy, Number theory+1
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
PAROVI
Medium7
Combinatorics, Graph+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
The Table in the Dream
Medium7
Simulation, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Air Play
Medium7
Combinatorics, Math
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Smallest Enclosing Sphere
Medium7
Geometry, Math
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Space Pirate
Medium7
Graph, Simulation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Pinball
Medium7
Dynamic programming, Segment tree
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Walking in JOI Kingdom
Medium7
Stack, Simulation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
High Card Low Card (Platinum)
Medium7
Greedy, Sorting
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Angry Cows
Medium7
Binary search, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Lights Out in the Barn
Medium7
String matching, Simulation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Train Fare
Medium7
BFS, Shortest path+1
No attempts yet
Time limit
2.5s
Memory limit
256 MB
Judgeable
Joy's Territory
Medium7
Geometry, Simulation+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Fenced In
Medium7
Minimum spanning tree, Greedy+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Circular Barn
Medium7
Dynamic programming, Prefix sum
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Blood groupsGiven the blood groups of N parents under N-allele inheritance, decide for each of Q queries whether the asked blood group can appear in their child.	Medium7	GraphCombinatorics	No attempts yet	3s	256 MB	Judgeable
Cake cutCarol picks a vertex of a convex cake and Carla picks a diagonal from it to split the cake, then Carol keeps the larger piece under optimal play from both.	Medium7	GeometryGame theory+1	No attempts yet	3s	256 MB	Judgeable
Exposing corruptionBribe members to switch parties within a budget while keeping rivals in different parties, and report the largest achievable DSP and PPP sizes.	Medium7	Dynamic programmingGraph+1	No attempts yet	3s	256 MB	Judgeable
Galactic TaxesFind the moment of the day that maximizes the cheapest path cost from office 1 to N when each edge tax changes linearly with time.	Medium7	Shortest pathBinary search	No attempts yet	3s	256 MB	Judgeable
Height MapCount the faces of the solid formed by grid columns of given heights, merging edge-adjacent unit squares on the same plane and direction into one face.	Medium7	BFSSorting+2	No attempts yet	3s	256 MB	Judgeable
Keep it energizedBuy energy packs at level shops so the stored energy covers each level cost in order for the least total cash.	Medium7	Dynamic programmingSegment tree+2	No attempts yet	3s	256 MB	Judgeable
Pyramid Base 2Find the largest axis-aligned square that fits on the grid so the total cost of removing the obstacles it overlaps stays within budget.	Medium7	Binary searchSegment tree+1	No attempts yet	5s	128 MB	Judgeable
CLARKSONSplit the lyrics into consecutive parts that each appear in the script and maximize the shortest part length.	Medium7	String matchingBinary search+1	No attempts yet	1s	256 MB	Judgeable
Traffic LightsFind the fastest drive from intersection S to D when each intersection only lets cars arriving from one road pass during each P-second window.	Medium7	Shortest pathGraph	No attempts yet	1s	256 MB	Judgeable
Stepping Stones on Ingyeong LakeChoose stones from 1 to N with jumps of length at most K so the product of the chosen numbers has as few trailing zeros as possible.	Medium7	Dynamic programmingGraph+1	No attempts yet	5s	256 MB	Judgeable
ARTUROrder the sticks so each one slides straight down off the table without touching the sticks still on it, choosing the lexicographically smallest such order.	Medium7	Topological sortGeometry+1	No attempts yet	1s	64 MB	Judgeable
AirportsFind the minimum number of planes needed to operate all scheduled flights when planes can take repositioning flights between them.	Medium7	GraphShortest path	No attempts yet	3s	256 MB	Judgeable
Falling BlocksPlace a repeating sequence of pentomino pieces on a 3 by 10 board with Tetris drops and row clears to maximize the count, or report forever.	Medium7	GraphDFS+2	No attempts yet	4s	256 MB	Judgeable
Racing GemsCollect as many gems as possible while running upward with limited sideways speed from any start position.	Medium7	Dynamic programmingSorting+1	No attempts yet	2s	256 MB	Judgeable
CoverageGiven towers with unit disk coverage, place one more disk to maximize the number of towers in one connected group.	Medium7	GeometryUnion-find+1	No attempts yet	3s	256 MB	Judgeable
Digit DivisionCount the ways to split a digit string into contiguous blocks so each block is divisible by m, modulo 1e9+7.	Medium7	Dynamic programmingMath+1	No attempts yet	1s	512 MB	Judgeable
Ice IgloosCount how many of up to 100000 small disjoint circles each of up to 100000 query segments passes through.	Medium7	GeometryMatrix	No attempts yet	10s	512 MB	Judgeable
GodzillaGuide mechs across open and ruined blocks to reach a clear row or column shot at Godzilla on his fixed path with the fewest homes destroyed.	Medium7	BFSSimulation+1	No attempts yet	2s	256 MB	Judgeable
HotelsFrom floor 0 with free elevator rides within residue classes, find the floor needing the most stair steps and report that count and the lowest such floor.	Medium7	Shortest pathGraph+2	No attempts yet	3s	256 MB	Judgeable
MarioBoats shuttle back and forth over fixed ranges and riders transfer only where two boats meet, so compute the earliest arrival at the far bank.	Medium7	Shortest pathGraph+1	No attempts yet	1s	256 MB	Judgeable
Amazing RaceChoose an order to visit task locations with service times, deadlines and travel times that fits in T minutes and earns the most points.	Medium7	Dynamic programmingBit manipulation+1	No attempts yet	5s	256 MB	Judgeable
Productivity improvementPartition all workers into exactly p nonempty lines to maximize the sum of each line's common overlapping work time.	Medium7	Dynamic programmingSorting+1	No attempts yet	2s	256 MB	Judgeable
DebuggingFind the single crashing line among n lines while balancing the cost of added print statements against the cost of each run.	Medium7	Dynamic programmingBinary search	No attempts yet	3s	256 MB	Judgeable
Elementary MathAssign +, -, or * to each of n given pairs so all results differ, choosing the lexicographically smallest valid assignment.	Medium7	GraphGreedy	No attempts yet	10s	256 MB	Judgeable
PromotionsGiven precedence rules and promotion counts A and B, count employees in every valid promotion set of each size and those in none of size B.	Medium7	Topological sortGraph	No attempts yet	2s	256 MB	Judgeable
LandscapingPick a final low or high level for every grid cell to minimize flip costs plus border charges between differing neighbors.	Medium7	Graph	No attempts yet	1s	256 MB	Judgeable
Game of CardsDecide the winner of a turn-based card game where each move trims one of many piles by up to K cards plus the value shown on the new top card.	Medium7	Game theoryDynamic programming	No attempts yet	1s	256 MB	Judgeable
LCM(i, j)Add the least common multiple over every pair i<j up to n and print the remainder modulo 1,000,000,007.	Medium7	Number theoryMath+1	No attempts yet	1s	256 MB	Judgeable
Sigma FunctionCount integers from 1 to m whose divisor sum is even, where m reaches 10^12.	Medium7	Number theoryMath	No attempts yet	1s	256 MB	Judgeable
Nim GameTwo players alternately remove stones from one pile and the player who takes the last stone loses, so print the winner under optimal play.	Medium7	Game theory	No attempts yet	1s	256 MB	Judgeable
Table GameTwo players alternately lower numbers in one row, and the player with no legal move loses, so determine the winner under optimal play.	Medium7	Game theoryBit manipulation+1	No attempts yet	1s	256 MB	Judgeable
AYBABTUYou cut k tree edges so each of the resulting k+1 regions holds a base and the total cut cost is smallest.	Medium7	Dynamic programmingTree	No attempts yet	10s	512 MB	Judgeable
Billiards SortingBall 1 moves through the triangular rack by swapping with a touching ball above or below, and the task asks for the fewest swaps that sort up to 15 balls.	Medium7	BFSGraph+1	No attempts yet	7s	512 MB	Judgeable
Longest LaneFind the longest straight segment that fits inside a simple polygon given in counterclockwise order.	Medium7	GeometryBrute force	No attempts yet	1s	512 MB	Judgeable
PLAY in BASICGiven a Music Macro Language score, find the character length of the shortest score with identical pitches, note lengths, volumes, and rests.	Medium7	Dynamic programmingSimulation+1	No attempts yet	5s	512 MB	Judgeable
Three-way BranchCount three-way downward paths from (1,1) to (W,H) on a grid with up to 30 blocked cells, modulo 1000000009.	Medium7	Dynamic programmingMatrix	No attempts yet	7s	64 MB	Judgeable
JAG-channel IIFind the lexicographically smallest member posting order consistent with the recorded top-to-bottom thread picks under move-to-front reordering.	Medium7	BacktrackingSimulation+1	No attempts yet	3s	256 MB	Judgeable
New Game AIGiven N characters with hp and dp values and a threshold C, count the characters that the order-dependent target scan can return over all reorderings.	Medium7	SortingGraph+1	No attempts yet	2s	256 MB	Judgeable
Sprinkler layoutSara tiles her fenced farm with tromino sprinklers around scarecrows using at most as many fence holes as fields.	Medium7	ImplementationSimulation+2	No attempts yet	1s	128 MB	Judgeable
WateringTile each 5x5 field with tromino sprinklers following the snake-order procedure and label them greedily with letters a to z.	Medium7	BacktrackingImplementation+2	No attempts yet	1s	128 MB	Judgeable
Binary vs DecimalFind the n-th positive integer whose decimal digits form a suffix of its binary representation.	Medium7	Number theoryBit manipulation+1	No attempts yet	1s	256 MB	Judgeable
Froggy FordYou may drop one extra stone anywhere between two river banks so the frog's crossing has the shortest possible longest hop.	Medium7	Binary searchGeometry+2	No attempts yet	1s	256 MB	Judgeable
Iceberg OrdersSimulate an order book with iceberg orders that match by best price then priority and refresh visible tips until each incoming order fills or rests.	Medium7	SimulationHeap+1	No attempts yet	1s	256 MB	Judgeable
The Brothers GameEach turn the opponent picks a step count from three values and you walk exactly that many directed edges, racing to end a turn on node N in the fewest turns.	Medium7	Game theoryGraph+1	No attempts yet	2s	256 MB	Judgeable
Bringing Order to DisorderCount the n-digit strings that come before the given string ordered by digit sum, then shifted-digit product, then numeric value.	Medium7	Dynamic programmingCombinatorics+1	No attempts yet	1s	256 MB	Judgeable
Alpaca SentenceFind the K-th string in lexicographic order among the shortest palindromes that contain S as a subsequence, or report NONE.	Medium7	Dynamic programmingString+1	No attempts yet	3s	256 MB	Judgeable
Being Solarly SystematicSimulate planetoids moving on a wrapping 3D grid and merging on shared cubes until no more collisions occur, then report the final planets.	Medium7	SimulationNumber theory+1	No attempts yet	1s	256 MB	Judgeable
Delete This!Find the fewest icons to move so a single box encloses all delete centers and excludes all keep centers.	Medium7	GeometryPrefix sum+1	No attempts yet	1s	256 MB	Judgeable
Transportation DelegationLink each factory to a distinct supplier through carrier chains that meet in shared states, using each carrier at most once, to supply as many as possible.	Medium7	Graph	No attempts yet	2s	256 MB	Judgeable
Trick ShotDecide whether one cue shot from a fixed line can chain three collisions to sink two balls in opposite corner holes.	Medium7	GeometryMath	No attempts yet	1s	256 MB	Judgeable
Shortest Complete SubarrayProcess point updates on an array and report the length of the shortest contiguous subarray containing every value from 1 to K, or -1 if none exists.	Medium7	Segment treeSliding window+1	No attempts yet	3s	512 MB	Judgeable
Namuk's Rotten Egg TrayPlace up to K nonoverlapping domino covers on an N by N tray to hide the most rottenness and report the remaining sum.	Medium7	BacktrackingSorting+1	No attempts yet	4s	512 MB	Judgeable
Fibonacci numbers and their greatest common divisorCompute the GCD of the nth and mth Fibonacci numbers for n and m up to 1e18, output modulo 1,000,000,007.	Medium7	Number theoryMatrix+1	No attempts yet	1s	256 MB	Judgeable
Rush HourStarting from node 1 with a rush-hour window that halves speed on flagged directed edges, compute each node earliest arrival time and report the largest.	Medium7	Shortest pathGraph+1	No attempts yet	1s	256 MB	Judgeable
TerroristsGiven a connected graph with at most 50 extra edges past a tree, answer the shortest distance for each query pair.	Medium7	Shortest pathTree	No attempts yet	5s	256 MB	Judgeable
AquariumFind the cheapest set of diagonal cell walls to remove so the whole R by C aquarium becomes one compartment.	Medium7	Minimum spanning treeUnion-find+1	No attempts yet	3s	256 MB	Judgeable
Jumping JoeyA frog visits pads in order, pulls ropes to drag upcoming pads closer, jumps gaps up to D, swims the rest, and needs the fewest swims.	Medium7	Dynamic programmingGreedy+1	No attempts yet	3s	256 MB	Judgeable
Primorial vs LCMGiven N, divide the least common multiple of 1 to N by the product of all primes up to N and print the quotient modulo 1000000007.	Medium7	Number theoryMath	No attempts yet	1s	256 MB	Judgeable
Building a Scholarship TableCount CGPA range tables with equal widths and arithmetic rates that spend exactly P units on the given students.	Medium7	Brute forceMath+1	No attempts yet	4s	256 MB	Judgeable
Tom and JerryTom runs from the center at speed V straight toward Jerry, who circles radius R at the same speed, so compute the catch time per test case.	Medium7	MathGeometry	No attempts yet	2s	256 MB	Judgeable
The Three-Way Splitting WeaponGiven three targets, find the launch angle whose projectile splits into three rays 25 degrees apart that strike all targets with the least speed.	Medium7	GeometryMath	No attempts yet	3s	256 MB	Judgeable
Performance Assessment 2Find the shortest sequence over 1 to M that is not a subsequence of A and count such sequences modulo 1e9+7.	Medium7	Dynamic programmingGreedy+1	No attempts yet	1s	256 MB	Judgeable
Wedding SelfieA convex polygon pinned at its first vertex rotates about the origin until the Y-axis halves its area, with ties broken by the most area below the X-axis.	Medium7	GeometryMath+1	No attempts yet	3s	256 MB	Judgeable
Mario and the Evil ToadPick K distinct non-root nodes of a weighted tree and order them to maximize the round trip from the root through them in order.	Medium7	Dynamic programmingTree+1	No attempts yet	3s	256 MB	Judgeable
Boring Planet PairsCount the planet pairs whose path xor is zero before any deletion and after each edge removal in order.	Medium7	Union-findHash map	No attempts yet	1s	64 MB	Judgeable
Endor ChameleonsChameleons walk a stick of length L, reverse and recolor on collision, and the total distance walked in each of K colors is reported.	Medium7	SimulationSorting	No attempts yet	1s	64 MB	Judgeable
SymmetryGiven up to 100000 planar points per test case, decide whether any line reflects the set onto itself.	Medium7	GeometryHash map+1	No attempts yet	2s	256 MB	Judgeable
Watermelons of the Field of WondersGiven N lines W0 + S*K, report the line with the largest value at each of M query days, breaking ties by smallest index.	Medium7	Segment treeSorting+1	No attempts yet	2s	256 MB	Judgeable
Martian KingAnswer rank, k-th, predecessor, and successor queries over the sorted binary color records of length-L routes from the capital to a regional center.	Medium7	Dynamic programmingBinary search+1	No attempts yet	2s	256 MB	Judgeable
CacheChoose which cached objects to evict for a known request sequence of sized objects with load costs to minimize total reload cost.	Medium7	Dynamic programmingBit manipulation	No attempts yet	1s	256 MB	Judgeable
Energetic turtleCount right-and-down grid paths from (0,0) to (N,M) that step on at most T of the K trap cells, modulo Z.	Medium7	CombinatoricsDynamic programming+1	No attempts yet	2s	256 MB	Judgeable
Weighing the stonesAfter each ranked stone is placed on pan 1 or pan 2, report whether pan 1 is heavier under every valid weight assignment, pan 2 is, or neither is certain.	Medium7	Segment treeGreedy+1	No attempts yet	1s	256 MB	Judgeable
K-th pathFind the K-th string in alphabetical order among all strings spelled by down-right paths from the top-left to the bottom-right of a letter grid.	Medium7	GreedyDynamic programming	No attempts yet	2s	256 MB	Judgeable
Beautiful rowCount distinct arrangements of the given numbers where every neighboring pair shares the same binary or ternary one-count.	Medium7	Dynamic programmingGraph+1	No attempts yet	3s	256 MB	Judgeable
XORPrint the start and length of the longest contiguous segment whose xor is at least x.	Medium7	TrieBit manipulation+1	No attempts yet	5s	256 MB	Judgeable
BiochipsPick exactly M nodes from a rooted tree with given values so no picked node is an ancestor of another and the sum is maximal.	Medium7	Dynamic programmingTree	No attempts yet	2s	512 MB	Judgeable
Monkey and Apple TreesCount ripe trees in each visited interval while other events ripen whole intervals, with every interval shifted by the previous count.	Medium7	Segment treeIntervals	No attempts yet	2s	256 MB	Judgeable
Luxury burrowFind the rectangle of area at least K whose minimum cell price is largest, breaking ties by larger area.	Medium7	Binary searchStack+1	No attempts yet	2s	64 MB	Judgeable
Gold Camp ForcefieldChoose a contiguous group of camps whose total energy covers the distance between its ends to maximize total gold.	Medium7	Segment treePrefix sum+1	No attempts yet	1s	256 MB	Judgeable
K blocksSplit the array into exactly K contiguous blocks so the sum of each block's maximum is as small as possible.	Medium7	Dynamic programmingStack+1	No attempts yet	1s	256 MB	Judgeable
Area covered by squaresCompute the total area covered by up to nine rotated squares given by center and vertex, counting overlaps once.	Medium7	GeometryCombinatorics	No attempts yet	2s	256 MB	Judgeable
Odd Even NimDecide whether the first player wins the odd-even Nim variant where even takes must leave stones and odd takes must clear the pile.	Medium7	Game theoryMath	No attempts yet	2s	512 MB	Judgeable
OOPCount for each pattern with one asterisk how many given words equal it after replacing the asterisk with any string, possibly empty.	Medium7	String matchingHash map+1	No attempts yet	2s	512 MB	Judgeable
Filling in the BracketsYou replace every ? with ( or ) to build the cheapest correct bracket string and take the lexicographically smallest one among ties.	Medium7	GreedyHeap	No attempts yet	1s	256 MB	Judgeable
PolygonSum the integers n between a and b for which some n-gon has all of its sides crossed by a single straight line.	Medium7	GeometryMath	No attempts yet	1s	256 MB	Judgeable
Min-cost GCDPay q per subtraction step and p per modulo step to reduce the pair (a, b) until one entry is zero, and report the cheapest total cost.	Medium7	GreedyNumber theory+1	No attempts yet	1s	32 MB	Judgeable
PAROVICount the nonempty sets of coprime pairs from 1 to N that cross every split point x, modulo 1,000,000,000.	Medium7	CombinatoricsGraph+1	No attempts yet	1s	64 MB	Judgeable
The Table in the DreamCount table cells holding values in each query interval, where each row starts at its index and each next entry adds the reversal of the previous entry.	Medium7	SimulationSorting+1	No attempts yet	5s	512 MB	Judgeable
Air PlayCount arrangements of N red and N blue stones in a row where the number of red-before-blue pairs is odd, modulo 1,000,000,007.	Medium7	CombinatoricsMath	No attempts yet	2s	512 MB	Judgeable
Smallest Enclosing SphereGiven N points in 3D space, find the radius of the smallest sphere containing all of them.	Medium7	GeometryMath	No attempts yet	2s	512 MB	Judgeable
Space PirateChange one teleporter destination, walk K jumps from star 1, and count the landing star over all N squared rewires.	Medium7	GraphSimulation	No attempts yet	2s	512 MB	Judgeable
PinballThe program installs the cheapest set of row devices so every falling ball lands in one bottom cell.	Medium7	Dynamic programmingSegment tree	No attempts yet	1s	512 MB	Judgeable
Walking in JOI KingdomN walkers start at given points and move east or west at speed 1, stopping when they meet anyone, and the task asks the positions of Q of them at time T.	Medium7	StackSimulation+1	No attempts yet	2s	512 MB	Judgeable
High Card Low Card (Platinum)Bessie orders her cards against Elsie's fixed sequence and picks when to flip scoring from high-wins to low-wins to maximize points.	Medium7	GreedySorting	No attempts yet	2s	512 MB	Judgeable
Angry CowsFind the smallest launch power whose chain of shrinking blast radii clears all hay bales on a line.	Medium7	Binary searchDynamic programming+1	No attempts yet	2s	512 MB	Judgeable
Lights Out in the BarnFor each polygon vertex, walk clockwise until angles and edge lengths reveal the start, then report the worst extra distance versus the shortest exit path.	Medium7	String matchingSimulation+1	No attempts yet	2s	512 MB	Judgeable
Train FareAfter each yearly fare hike from 1 to 2 yen, report how many cities have a cheapest fare to city 1 above the original all-1-yen cost.	Medium7	BFSShortest path+1	No attempts yet	2.5s	256 MB	Judgeable
Joy's TerritoryCount the unit squares with all four corners visited by repeating the same N-step walk for K days from each day's endpoint.	Medium7	GeometrySimulation+2	No attempts yet	1s	256 MB	Judgeable
Fenced InRemove fence segments between adjacent field regions so every region connects with the smallest possible total removed length.	Medium7	Minimum spanning treeGreedy+1	No attempts yet	2s	512 MB	Judgeable
Circular BarnChoose up to k outer doors on a ring of n rooms so the total clockwise walking distance to every cow room is minimized.	Medium7	Dynamic programmingPrefix sum	No attempts yet	2s	512 MB	Judgeable