Problems

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Total results29,109 problems

Cellular Network
Medium7
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Archery
Medium7
Geometry, Intervals+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Processor
Medium7
Binary search, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Network
Medium7
Greedy, Tree
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Travel
Medium7
Graph, DFS
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tree
Medium7
Geometry, Tree+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Log Jumping
Medium7
Intervals, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
PushPush
Medium7
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Seminar Room
Medium7
Graph, DFS+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bond
Medium7
Graph, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Wire Connection
Medium7
Greedy, Intervals+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fair Share
Medium7
Graph, Binary search
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Aquarium 1
Medium7
Simulation, Geometry+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sticks
Medium7
Dynamic programming, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Picking Game
Medium7
Graph
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
ChonSu
Medium7
Tree, Divide and conquer+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Lost Lists
Medium7
Backtracking, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Castle
Medium7
Graph, Geometry+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Parents
Medium7
Dynamic programming, Tree
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Number Puzzle
Medium7
Math, Graph
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Subway Map
Medium7
Backtracking, Geometry+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cube
Medium7
Geometry, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Electric Network
Medium7
DFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
L-Shape Covering
Medium7
Geometry, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Delivery
Medium7
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Homework
Medium7
Backtracking, Greedy+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Nile River Dam Releases
Medium7
Dynamic programming, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Surveillance System
Medium7
Greedy, Intervals+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Two Rectangles
Medium7
Geometry, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Random Game
Medium7
Binary search, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Safe
Medium7
Math, Matrix
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Chicken Shop Placement
Medium7
Geometry
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
King and Pawn
Medium7
Game theory, Recursion+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sightseeing
Medium7
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Oh, Those Achin' Feet
Medium7
Shortest path, BFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Queens on a Torus
Medium7
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bulletin boards
Medium7
Dynamic programming, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Counting ponorks
Medium7
Geometry, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Disperse!
Medium7
Combinatorics, Geometry+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tokens
Medium7
Two pointers, Prefix sum
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Young, Poor and Busy
Medium7
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Nim
Medium7
Game theory, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Super Star
Medium7
Geometry, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Ye Holy Hand Grenades!
Medium7
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
I can solve problem 9999
Medium7
Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mersenne Composite Numbers
Medium7
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Lottery Tickets
Medium7
Dynamic programming, String matching
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Triangle
Medium7
Geometry
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Baffled!
Medium7
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The jury is out
Medium7
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Box Toppling
Medium7
Backtracking, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Molecules, Molecules
Medium7
Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Molecules, Molecules 2
Medium7
Graph, Matrix
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stir-Frying Carrots
Medium7
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pinball
Medium7
Geometry, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cliff Walking
Medium7
Shortest path, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Suffix Array
Medium7
String matching, Sorting
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Longest Common Substring
Medium7
String matching, Binary search+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Russian Dolls
Medium7
Dynamic programming, Sorting+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Intercity
Medium7
Shortest path, Graph+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Making S with two cells
Medium7
Number theory, Math+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Sanggeun's Idea
Medium7
Number theory, Combinatorics
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Rabbits and Sanggeun
Medium7
Graph, DFS
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Protecting the Vegetables
Medium7
Geometry, Sorting+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Tram
Medium7
Heap, Sorting+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Board Game "Tree"
Medium7
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Let's go on an adventure
Medium7
Dynamic programming, Shortest path+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dreaded Alternating Game
Medium7
Game theory, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Seven Kingdoms
Medium7
Graph, DFS+2
No attempts yet
Time limit
9s
Memory limit
128 MB
Judgeable
Institute of Advanced Category Manipulation
Medium7
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Digital Content Protection
Medium7
Greedy, Tree+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Chemicals Monitoring
Medium7
Dynamic programming, Stack+2
No attempts yet
Time limit
4s
Memory limit
256 MB
Judgeable
Movie Theater Seating
Medium7
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
2s
Memory limit
64 MB
Judgeable
Magic Graphs
Medium7
Graph, DFS
No attempts yet
Time limit
2s
Memory limit
64 MB
Judgeable
Do Not Disturb!
Medium7
Probability, Matrix+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
You Shall Not Pass!!
Medium7
Dynamic programming, Tree
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cipher
Medium7
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Encoded Coordinates
Medium7
Matrix, Number theory
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Sneaking Through the Corridor
Medium7
Union-find, Geometry+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Surveillance Camera
Medium7
Geometry, Math+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Prison Break
Medium7
Shortest path, BFS+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Hurry Plotter
Medium7
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
ACM Coalition
Medium7
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fruit Weights
Medium7
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Royal Gems
Medium7
Dynamic programming, Backtracking+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Conditional Statements
Medium7
Intervals, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
World Cup Nominations
Medium7
Graph, DFS
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Mayo Empire
Medium7
Tree, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Diamonds
Medium7
Dynamic programming, Intervals+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Border Conflict
Medium7
Dynamic programming, Geometry+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Goguryeo and the Crown Prince
Medium7
String matching, Probability
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Array Game
Medium7
Dynamic programming, Intervals
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
ACM Revenge
Medium7
Tree, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Jeju Island Tour
Medium7
Dynamic programming, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Drop Zone
Medium7
Graph, BFS
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Probability Paradox
Medium7
Probability, String matching+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Letter Cubes
Medium7
Backtracking, Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Item Crafting
Medium7
Shortest path, Graph+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Flight Boarding Optimization
Medium7
Dynamic programming, Intervals+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Heavy Chain Clusterization
Medium7
Graph, String
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Cellular NetworkYou sort n cells by their probabilities and split them into w ordered zones to minimize the expected number of paged cells.	Medium7	Dynamic programmingSorting+1	No attempts yet	1s	128 MB	Judgeable
ArcheryDecide whether some spot on the archer line fires one straight shot through every horizontal target segment.	Medium7	GeometryIntervals+1	No attempts yet	1s	128 MB	Judgeable
ProcessorFind the smallest integer processor speed that lets every preemptive job finish between its release time and deadline.	Medium7	Binary searchGreedy+2	No attempts yet	1s	128 MB	Judgeable
NetworkPlace the fewest additional servers on internal nodes so every leaf is within distance k of the nearest server.	Medium7	GreedyTree	No attempts yet	1s	128 MB	Judgeable
TravelDecide whether a simple cycle exists that uses two required roads and avoids all toll roads.	Medium7	GraphDFS	No attempts yet	1s	128 MB	Judgeable
TreeDraw a crossing-free straight-line tree through n given points so each point has its required degree.	Medium7	GeometryTree+2	No attempts yet	1s	128 MB	Judgeable
Log JumpingFind the largest set of equal-length logs that can be visited in a closed tour where jumps are allowed between logs whose segments share a point.	Medium7	IntervalsSorting+1	No attempts yet	1s	128 MB	Judgeable
PushPushPush rocks one cell at a time across a grid map to walk from the entrance to the treasure.	Medium7	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
Seminar RoomEach group submits two candidate time intervals, and the program picks one per group so that no two chosen intervals overlap.	Medium7	GraphDFS+1	No attempts yet	1s	128 MB	Judgeable
BondDecide for each test case whether some connected loopless multigraph has exactly the given valencies as degrees.	Medium7	GraphMath	No attempts yet	1s	128 MB	Judgeable
Wire ConnectionChoose the fewest vias so vertical wires from the power line to those vias cross every horizontal wire.	Medium7	GreedyIntervals+1	No attempts yet	1s	128 MB	Judgeable
Fair ShareAssign each job to one of its two allowed processors to minimize the largest load on any processor.	Medium7	GraphBinary search	No attempts yet	1s	128 MB	Judgeable
Aquarium 1Given a stepped aquarium bottom with drain holes, compute the volume of water that stays trapped after drainage.	Medium7	SimulationGeometry+1	No attempts yet	1s	128 MB	Judgeable
SticksYou keep a connected set of sticks that meet only at endpoints without crossing to maximize total length.	Medium7	Dynamic programmingGraph+2	No attempts yet	1s	128 MB	Judgeable
Picking GameMatch crossing horizontal and vertical segments to maximize the pair count, then the total weight product.	Medium7	Graph	No attempts yet	10s	256 MB	Judgeable
ChonSuGiven the distances between consecutive leaves of an unknown full binary tree, compute the distance between two specified leaves.	Medium7	TreeDivide and conquer+1	No attempts yet	1s	128 MB	Judgeable
Lost ListsRebuild the lexicographically smallest increasing list of distinct positive integers matching each sorted pairwise sum list, or print -1 when none exists.	Medium7	BacktrackingSorting+1	No attempts yet	1s	128 MB	Judgeable
CastleDecide whether n given points form the vertices of a simple rectilinear polygon whose edges alternate between horizontal and vertical.	Medium7	GraphGeometry+1	No attempts yet	1s	128 MB	Judgeable
ParentsPick from 1 to K nodes of a valued tree with no parent-child pair so the sum of picked values is as large as possible.	Medium7	Dynamic programmingTree	No attempts yet	5s	128 MB	Judgeable
Number PuzzleDecide whether a path joining the two marked cells visits every cell of an even by even grid exactly once.	Medium7	MathGraph	No attempts yet	5s	128 MB	Judgeable
Subway MapDecide whether every station label fits above or below the line covering its own station point and no other, with no two labels overlapping.	Medium7	BacktrackingGeometry+1	No attempts yet	1s	128 MB	Judgeable
CubeRomy starts on the top face of a side-8 cube and Nancy sits elsewhere on its surface, and each case asks for the squared length of the shortest surface path.	Medium7	GeometryBrute force	No attempts yet	1s	128 MB	Judgeable
Electric NetworkGiven a connected network, compute the fewest new lines that keep every pair of facilities connected after any single line fails.	Medium7	DFSGraph+2	No attempts yet	1s	128 MB	Judgeable
L-Shape CoveringFind the minimum area of an axis-aligned L-shape with its top-right corner cut away covering all given points.	Medium7	GeometrySorting	No attempts yet	1s	128 MB	Judgeable
DeliveryJim starts at 0, carries at most one parcel at a time between points on a road, and returns to 0 after delivering all parcels over the shortest total distance.	Medium7	GreedySorting+1	No attempts yet	1s	128 MB	Judgeable
HomeworkChoose the phone call order that lets all N students finish their homework in the shortest time.	Medium7	BacktrackingGreedy+1	No attempts yet	2s	128 MB	Judgeable
Nile River Dam ReleasesSchedule dam releases so every forecast window gets a release and cascades flow downstream, at the lowest total cost.	Medium7	Dynamic programmingGreedy+1	No attempts yet	1s	128 MB	Judgeable
Surveillance SystemPick the fewest cameras whose clockwise ranges together cover all 100000 sectors on the circular boundary.	Medium7	GreedyIntervals+1	No attempts yet	1s	128 MB	Judgeable
Two RectanglesCover all given points with two non-overlapping axis-aligned rectangles and minimize the larger area.	Medium7	GeometrySorting	No attempts yet	1s	128 MB	Judgeable
Random GamePick win probabilities for the games so the lower of the two players' expected scores is as large as possible.	Medium7	Binary searchMath+1	No attempts yet	1s	128 MB	Judgeable
The SafePressing one knob flips its whole row and column, and you must make every knob horizontal with the fewest presses.	Medium7	MathMatrix	No attempts yet	1s	128 MB	Judgeable
Chicken Shop PlacementFind the 3D point that minimizes its distance to the farthest of up to 5000 given planets, and report that distance with its coordinates.	Medium7	Geometry	No attempts yet	1s	128 MB	Judgeable
King and PawnPredict whether the king captures the pawn or the pawn escapes on an 8x8 board with forbidden and danger cells when both play best.	Medium7	Game theoryRecursion+1	No attempts yet	1s	128 MB	Judgeable
SightseeingCount the routes from city S to city F whose length equals the shortest distance or is exactly one unit longer.	Medium7	Shortest pathGraph+1	No attempts yet	1s	128 MB	Judgeable
Oh, Those Achin' FeetSplit each route's pedestrian load evenly across all shortest street paths and print every square's total load.	Medium7	Shortest pathBFS+2	No attempts yet	1s	128 MB	Judgeable
Queens on a TorusDecide for each N whether N queens fit on an N by N torus board without sharing a wrapping row, column or diagonal.	Medium7	Number theoryMath	No attempts yet	1s	128 MB	Judgeable
Bulletin boardsArrange ordered framed pictures into consecutive strips with shared frames and centering to fit the smallest area rectangle.	Medium7	Dynamic programmingSimulation	No attempts yet	1s	128 MB	Judgeable
Counting ponorksCount unit steps to walk a right-angled wall route where steps cut straight across corners and a final partial step of at least half a unit counts as one.	Medium7	GeometrySimulation+1	No attempts yet	1s	128 MB	Judgeable
Disperse!Count the ways to split an N by N grid into two congruent halves along cell edges with perimeter exactly M.	Medium7	CombinatoricsGeometry+1	No attempts yet	1s	128 MB	Judgeable
TokensFor each token with given length and lookahead, compute how far back its text affects earlier token boundaries.	Medium7	Two pointersPrefix sum	No attempts yet	1s	128 MB	Judgeable
Young, Poor and BusyTwo travelers starting from Hakodate and Tokyo meet in one city for at least 30 minutes and both return home between 08:00 and 18:00 at the lowest total fare.	Medium7	Shortest pathGraph+1	No attempts yet	1s	128 MB	Judgeable
NimDecide whether the moving-first team wins the team take-away game with per-player take limits where the last take loses.	Medium7	Game theoryDynamic programming+1	No attempts yet	1s	128 MB	Judgeable
Super StarRead up to 29 points in 3D space and print the radius of the smallest sphere that contains all of them.	Medium7	GeometryBrute force	No attempts yet	1s	128 MB	Judgeable
Ye Holy Hand Grenades!Judge whether each rabbit survives a blast from the fixed resting place of a unit grenade in an exponential and log valley.	Medium7	GeometryMath	No attempts yet	1s	128 MB	Judgeable
I can solve problem 9999Choose yes or no votes for everyone to minimize disagreeing friendships plus votes cast against personal belief.	Medium7	Graph	No attempts yet	1s	128 MB	Judgeable
Mersenne Composite NumbersFactor every composite Mersenne number 2^P - 1 for prime P up to K and print the factorizations in increasing order.	Medium7	Number theoryMath	No attempts yet	1s	128 MB	Judgeable
Lottery TicketsCount numbers from 0 to M-1 whose zero-padded decimal form matches Z in some length-r block at the same positions.	Medium7	Dynamic programmingString matching	No attempts yet	1s	128 MB	Judgeable
TriangleDecide for up to 1000 pairs of disjoint triangular loops in 3D whether the two loops are linked or can be separated by rigid motion.	Medium7	Geometry	No attempts yet	1s	128 MB	Judgeable
Baffled!The program reads a baffled grid tank and reports how much water fits before trapped air stops filling.	Medium7	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
The jury is outSelect k of up to 100 candidates with the closest prosecution and defence totals, breaking ties by larger combined score then smaller index list.	Medium7	Dynamic programming	No attempts yet	1s	128 MB	Judgeable
Box TopplingDecide if every standing box on an n by n floor can be toppled flat in some order and direction without leaving the floor or overlapping.	Medium7	BacktrackingBrute force+1	No attempts yet	1s	128 MB	Judgeable
Molecules, MoleculesDecide whether grid atoms can be linked to orthogonal neighbors so each carbon, nitrogen, oxygen, and hydrogen has 4, 3, 2, and 1 bonds.	Medium7	Graph	No attempts yet	1s	128 MB	Judgeable
Molecules, Molecules 2The program decides whether neighboring grid atoms can be bonded so every C has 4 bonds, N has 3, O has 2, and H has 1.	Medium7	GraphMatrix	No attempts yet	1s	128 MB	Judgeable
Stir-Frying CarrotsFind the fewest knife cuts that split carrots of given weights into real-valued pieces whose lightest-to-heaviest ratio exceeds T.	Medium7	GreedyMath+1	No attempts yet	1s	128 MB	Judgeable
PinballA ball falls straight down from x0 onto slanted segments, slides down each hit segment to its lower end, and the task asks for the final x coordinate.	Medium7	GeometrySorting+1	No attempts yet	1s	128 MB	Judgeable
Cliff WalkingFind the farthest square reachable on a 12-hour round trip over a tidal grid, stepping only between squares within 1m of height after each dried for an hour.	Medium7	Shortest pathGraph+2	No attempts yet	1s	128 MB	Judgeable
Suffix ArrayRead a lowercase string of length up to 500000 and print its suffix array and LCP array, writing x for the first LCP entry.	Medium7	String matchingSorting	No attempts yet	3s	256 MB	Judgeable
Longest Common SubstringFind the length of the longest substring shared by two lowercase strings and print the lexicographically smallest one of that length.	Medium7	String matchingBinary search+2	No attempts yet	1s	256 MB	Judgeable
Russian DollsArrange all dolls into nested chains where each doll fits only inside a strictly roomier one to minimize the total cost of leftover empty space.	Medium7	Dynamic programmingSorting+1	No attempts yet	3s	128 MB	Judgeable
IntercityFind the cheapest fare from city 1 to city N in a complete graph where K given edges cost A and all other edges cost B.	Medium7	Shortest pathGraph+1	No attempts yet	3s	128 MB	Judgeable
Making S with two cellsYou start with cells holding a and b, repeatedly add one cell to the other, and must decide whether the value S can ever appear in either cell.	Medium7	Number theoryMath+1	No attempts yet	2s	128 MB	Judgeable
Sanggeun's IdeaCompute the sum of gcds over all pairs of values 2^(2^n)+1 for n from n1 to n2.	Medium7	Number theoryCombinatorics	No attempts yet	2s	128 MB	Judgeable
Rabbits and SanggeunDecide whether deleting vertices and edges can leave a connected subgraph with exactly four degree-one vertices.	Medium7	GraphDFS	No attempts yet	2s	128 MB	Judgeable
Protecting the VegetablesFind the minimum-perimeter rectangle of any orientation that encloses all given points.	Medium7	GeometrySorting+1	No attempts yet	2s	128 MB	Judgeable
TramEach boarding passenger takes the empty seat farthest from the nearest seated passenger in a 2-column tram, with ties broken by row then column.	Medium7	HeapSorting+2	No attempts yet	1s	256 MB	Judgeable
Board Game "Tree"Find the minimum moves between two nodes given as root paths in a binary tree with same-level sideways edges.	Medium7	Shortest pathGraph+1	No attempts yet	1s	256 MB	Judgeable
Let's go on an adventurePlan a route from the start to the destination within a fuel limit that collects the largest possible total of region values, counting each visited region once.	Medium7	Dynamic programmingShortest path+1	No attempts yet	1s	128 MB	Judgeable
Dreaded Alternating GamePick the side, even or odd, that wins a token-moving game on a directed board when both players play perfectly.	Medium7	Game theoryGraph+2	No attempts yet	1s	128 MB	Judgeable
Seven KingdomsDecide whether the cities split into three cliques holding city 1, city 2, and the rest, and print the lexicographically smallest assignment or impossible.	Medium7	GraphDFS+2	No attempts yet	9s	128 MB	Judgeable
Institute of Advanced Category ManipulationDecide which universities can tie for first under some weighted sum of their three scores.	Medium7	GeometryMath	No attempts yet	1s	128 MB	Judgeable
Digital Content ProtectionGiven the hacked leaves of a complete binary key tree, print the identifiers of the smallest set of unexposed node keys covering every intact player.	Medium7	GreedyTree+1	No attempts yet	2s	128 MB	Judgeable
Chemicals MonitoringVictor admits the maximum-priority subset of streams that one shared output unit can report in stack order.	Medium7	Dynamic programmingStack+2	No attempts yet	4s	256 MB	Judgeable
Movie Theater SeatingDecide whether S solo guests and C couples fit into R rows of 8 seats with reserved seats while keeping neighbors and front seats empty.	Medium7	Dynamic programmingBit manipulation+1	No attempts yet	2s	64 MB	Judgeable
Magic GraphsPick one label from each of K pairs so that no two chosen labels are the positive and negative of the same number.	Medium7	GraphDFS	No attempts yet	2s	64 MB	Judgeable
Do Not Disturb!Two people wander a graph at random each step, and you must find the expected time until both reach node C at once.	Medium7	ProbabilityMatrix+1	No attempts yet	1s	128 MB	Judgeable
You Shall Not Pass!!Choose up to C coaching subtrees in a forest to maximize the number of teams covered by at least one chosen subtree.	Medium7	Dynamic programmingTree	No attempts yet	1s	128 MB	Judgeable
CipherGiven total character volume, word count, and rank, reconstruct the I-th message in lexicographic order or report corruption.	Medium7	Dynamic programmingCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
Encoded CoordinatesGiven two linear recurrences sharing one missing initial value and the first output, find the second output or report UNKNOWN when it is not unique.	Medium7	MatrixNumber theory	No attempts yet	5s	128 MB	Judgeable
Sneaking Through the CorridorFind the largest radius of a circle that can travel between two walls past circular sensors without entering any range.	Medium7	Union-findGeometry+1	No attempts yet	5s	256 MB	Judgeable
Surveillance CameraCompute the share of a convex polygon covered by a 90-degree camera at the midpoint of its first edge, printed as a reduced fraction.	Medium7	GeometryMath+1	No attempts yet	2s	128 MB	Judgeable
Prison BreakTwo prisoners must reach the outside of a grid map, and the task asks for the fewest doors to open so both escape.	Medium7	Shortest pathBFS+1	No attempts yet	1s	256 MB	Judgeable
Hurry PlotterMaximize the number of horizontal segments a sweeping plotter draws within a time limit, where drawn moves cost double and the final row skips the return trip.	Medium7	Dynamic programmingSorting+1	No attempts yet	1s	128 MB	Judgeable
ACM CoalitionPick parties whose seats cover the shortage and grant one demand each so ACM's remaining board votes are maximal.	Medium7	Dynamic programming	No attempts yet	1s	128 MB	Judgeable
Fruit WeightsGiven inequalities between multiples of unknown fruit weights, decide if the query, its reverse, both, or neither must hold, or the givens contradict.	Medium7	Shortest pathGraph	No attempts yet	1s	128 MB	Judgeable
Royal GemsFill each cell of an n by m board with one of four gems to maximize the ruby count while every ruby, emerald, and sapphire neighbors the required higher gems.	Medium7	Dynamic programmingBacktracking+2	No attempts yet	1s	128 MB	Judgeable
Conditional StatementsGiven one-variable if lines that switch on numbered lights, delete as many lines as possible without changing which lights turn on for any input values.	Medium7	IntervalsHash map+1	No attempts yet	1s	128 MB	Judgeable
World Cup NominationsGiven every pairwise duel result, count the countries that can emerge last under some knockout pairing order.	Medium7	GraphDFS	No attempts yet	1s	128 MB	Judgeable
The Mayo EmpireEach new city joins the tree by one road with possible capital moves, and the task sums the farthest road count from the capital after every addition.	Medium7	TreeGreedy	No attempts yet	1s	128 MB	Judgeable
DiamondsArthas opens boxes outward from his starting keys to collect every diamond with the fewest openings.	Medium7	Dynamic programmingIntervals+1	No attempts yet	1s	128 MB	Judgeable
Border ConflictChoose the shortest subsequence polyline through the given points so every original point lies within distance D of it.	Medium7	Dynamic programmingGeometry+1	No attempts yet	1s	128 MB	Judgeable
Goguryeo and the Crown PrinceGiven two different binary strings of equal length, compute the probability that the first appears before the second in fair coin flips.	Medium7	String matchingProbability	No attempts yet	1s	128 MB	Judgeable
Array GameThe player shifts all numbers left or right each turn to maximize the total signed value collected when numbers land on fixed plus and minus cells.	Medium7	Dynamic programmingIntervals	No attempts yet	1s	128 MB	Judgeable
ACM RevengeCompute the number of deaths before the first hunter reaches a treasure room in a binary tree with traps and toggling exits.	Medium7	TreeDynamic programming+1	No attempts yet	1s	128 MB	Judgeable
Jeju Island TourPick two vertex-disjoint directed paths in a DAG so the total number of vertices on both paths is as large as possible.	Medium7	Dynamic programmingGraph+1	No attempts yet	1s	128 MB	Judgeable
Drop ZoneSeal the single connected drop zone off from the map border with the fewest unit-cost barricades between orthogonally adjacent open cells.	Medium7	GraphBFS	No attempts yet	2s	128 MB	Judgeable
Probability ParadoxTwo players each pick a coin-flip pattern and the program computes the chance the first pattern appears before the second.	Medium7	ProbabilityString matching+1	No attempts yet	1s	128 MB	Judgeable
Letter CubesGiven words that a set of letter cubes can spell, deduce which six letters sit on each cube.	Medium7	BacktrackingGraph	No attempts yet	1s	128 MB	Judgeable
Item CraftingCompute the minimum money to get item 1 by buying items or crafting items from pairs of other items.	Medium7	Shortest pathGraph+1	No attempts yet	2s	256 MB	Judgeable
Flight Boarding OptimizationYou split the rows into k contiguous zones and order their boarding phases, keeping queue order inside each zone, to minimize total boarding difficulty.	Medium7	Dynamic programmingIntervals+1	No attempts yet	2s	256 MB	Judgeable
Heavy Chain ClusterizationSplit n antibody chains into the fewest groups so each group shares the same first k or last k letters.	Medium7	GraphString	No attempts yet	2s	256 MB	Judgeable