Problems

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Total results29,417 problems

The Carpenter
Hard8
Dynamic programming, Matrix+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Patience
Hard8
Combinatorics, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Intuitionistic Logic
Hard8
Brute force, Graph+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Ferries
Hard8
Shortest path, Greedy+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Battleships
Hard8
Backtracking, Brute force+1
No attempts yet
Time limit
10s
Memory limit
128 MB
Judgeable
Rent-A-Pixel
Hard8
Geometry, Intervals+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Stampede!
Hard8
Graph, Binary search
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Tree Lighting
Hard8
Geometry, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
RNA
Hard8
Dynamic programming, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Triple
Hard8
Combinatorics, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Light Switches
Hard8
Number theory, Math
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Assimilation
Hard8
Game theory, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Manifest Destiny
Hard8
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Polarization
Hard8
Tree, Dynamic programming+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Byteocircle
Hard8
Shortest path, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Euler's Problem
Hard8
Number theory, Backtracking+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pebbles
Hard8
Game theory, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Histograms
Hard8
Dynamic programming, Prefix sum
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Bridges
Hard8
Graph, Intervals+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Sugar Glider
Hard8
Shortest path, Heap
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Blocks
Hard8
Simulation, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Buffed Buffet
Hard8
Dynamic programming, Binary search+2
No attempts yet
Time limit
4s
Memory limit
128 MB
Judgeable
Winning Strategy
Hard8
Game theory, Graph+1
No attempts yet
Time limit
8s
Memory limit
128 MB
Judgeable
Maze reduction
Hard8
Graph, Hash map+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Metal Processing Plant
Hard8
Graph, Union-find+1
No attempts yet
Time limit
4s
Memory limit
128 MB
Judgeable
Pachinko
Hard8
Probability, Graph+1
No attempts yet
Time limit
6s
Memory limit
512 MB
Judgeable
Sensor Network
Hard8
Backtracking, Graph+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Eunki's DNA Molecules
Hard8
Math, String+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Beads and Wires
Hard8
Dynamic programming, Tree+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Wall
Hard8
Segment tree
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Game
Hard8
Graph, Greedy+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Agent 007
Hard8
Game theory, Shortest path+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
The Wall
Hard8
Shortest path, Graph
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Snake
Hard8
Backtracking, Graph+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Cards
Hard8
Segment tree, Dynamic programming
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Criminals
Hard8
String matching, Greedy+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Supercomputer
Hard8
Tree, Prefix sum+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Rally
Hard8
Topological sort, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Tourist Information Points
Hard8
Dynamic programming, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Vials
Hard8
Union-find, Simulation+2
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Tribes
Hard8
Union-find, Segment tree+2
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Persuading the Advisers
Hard8
Game theory, Tree+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Doubling game
Hard8
Dynamic programming, BFS+1
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
The kingdom
Hard8
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Recovering the Populations
Hard8
Tree, DFS+1
No attempts yet
Time limit
4s
Memory limit
256 MB
Judgeable
Self-Describing Sequences
Hard8
Math, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Test Data Analysis
Hard8
Dynamic programming, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Fertilizing
Hard8
Segment tree, Sorting+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Saveit
Hard8
Graph, BFS+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
A Die Maker
Hard8
BFS, Greedy+2
No attempts yet
Time limit
8s
Memory limit
256 MB
Judgeable
Cheats
Hard8
Dynamic programming, Tree+1
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Fantastic Problem
Hard8
Segment tree, Number theory+1
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Gold Bandits
Hard8
Shortest path, Graph
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Super Mario 169
Hard8
Dynamic programming, Geometry+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Particle Swapping
Hard8
Minimum spanning tree, Graph+2
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Floor Painting
Hard8
Geometry, Binary search
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Pawns
Hard8
Game theory, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Lengthy Traveling Salesman
Hard8
Tree, Greedy
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Sweet War
Hard8
Game theory, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
L∞ Jumps
Hard8
Divide and conquer, Geometry+2
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
The Leprechaun Hunt
Hard8
Game theory, Graph+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Shrine Maintenance
Hard8
Dynamic programming, Geometry+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Multi-Machine Scheduling of Two Applications
Hard8
Binary search, Greedy+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Hari Merdeka
Hard8
Dynamic programming, String matching
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Marbles in a Circle
Hard8
Number theory, Math+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Inspectors
Hard8
Graph, Combinatorics
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Watch, Man!
Hard8
Graph, Geometry
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Galaxy collision
Hard8
Graph, BFS+2
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Journey through the kingdom
Hard8
Shortest path, Segment tree
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Knights of the Round Table
Hard8
Combinatorics, Math
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Farey Sequence Sum
Hard8
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Mokia
Hard8
Divide and conquer, Segment tree
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Marbles
Hard8
Geometry, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Road Repair
Hard8
Tree, Divide and conquer+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
String Transformation
Hard8
Tree, Stack+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
How Does Your Garden Grow?
Hard8
Dynamic programming, Math+1
No attempts yet
Time limit
30s
Memory limit
256 MB
Judgeable
Line Sweep
Hard8
Greedy, Intervals+2
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Shotcube
Hard8
BFS, Graph+1
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Out of context
Hard8
Dynamic programming, String matching
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Parades
Hard8
Dynamic programming, Tree+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Mountainous landscape
Hard8
Geometry, Stack
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Virus synthesis
Hard8
Dynamic programming, String matching
No attempts yet
Time limit
20s
Memory limit
256 MB
Judgeable
The Imp
Hard8
Game theory, Dynamic programming+1
No attempts yet
Time limit
15s
Memory limit
256 MB
Judgeable
Around the Track
Hard8
Geometry, Shortest path+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Money Transfers
Hard8
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Volunteer Camp
Hard8
Tree, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Enchanted Forest
Hard8
Union-find, Sorting+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Norma's array price sum
Hard8
Divide and conquer, Stack
No attempts yet
Time limit
3s
Memory limit
64 MB
Judgeable
Truck Encounters
Hard8
Intervals, Sorting+1
No attempts yet
Time limit
3s
Memory limit
64 MB
Judgeable
Transmutation Circles
Hard8
Dynamic programming, Tree+1
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Containment
Hard8
Graph, Geometry
No attempts yet
Time limit
20s
Memory limit
256 MB
Judgeable
Integer Game
Hard8
Game theory, Dynamic programming
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Stamp Stamp
Hard8
Dynamic programming, Graph+2
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Cactus Generator
Hard8
Graph, Union-find+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Damage Assessment
Hard8
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Improvements
Hard8
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Line Fitting Under Uncertainty
Hard8
Binary search, Geometry+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Polygon Guards
Hard8
Geometry, Brute force+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Integer in Integer
Hard8
Dynamic programming, String matching+1
No attempts yet
Time limit
10s
Memory limit
128 MB
Judgeable
Molecule Pair Distance Histogram
Hard8
Divide and conquer, Matrix+2
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
The CarpenterCut two non-overlapping diagonal triangles from an n by m black-and-white board and glue them into the largest square with alternating colors.	Hard8	Dynamic programmingMatrix+1	No attempts yet	2s	128 MB	Judgeable
PatienceGiven n, count the unfinished-suit layouts with fewer than n high cards out of place that reach the ordered row.	Hard8	CombinatoricsDynamic programming+1	No attempts yet	2s	512 MB	Judgeable
Intuitionistic LogicGiven a DAG and its antichain algebra, test each formula over all variable assignments and report valid or invalid.	Hard8	Brute forceGraph+2	No attempts yet	2s	128 MB	Judgeable
FerriesCaptains at each island reassign fixed ferry fares among destinations to maximize the cheapest fare from island 1 to island N.	Hard8	Shortest pathGreedy+2	No attempts yet	2s	512 MB	Judgeable
BattleshipsCount the fleets that fit the given row and column sums on a 10x10 board, then name the smallest one or two cell reveals that leave exactly one fleet.	Hard8	BacktrackingBrute force+1	No attempts yet	10s	128 MB	Judgeable
Rent-A-PixelCompute the smallest row- and column-convex block set containing the given blocks and print its outline corners clockwise.	Hard8	GeometryIntervals+1	No attempts yet	3s	128 MB	Judgeable
Stampede!Move n pieces from the left column to the right column on an obstacle grid without collisions in the fewest simultaneous turns.	Hard8	GraphBinary search	No attempts yet	5s	128 MB	Judgeable
Tree LightingA point light shines a bounded wedge upward through absorbing and mirrored segments, and you report the lit percentage of a horizontal house front.	Hard8	GeometrySimulation+1	No attempts yet	1s	128 MB	Judgeable
RNAReport the longest contiguous block shared by both RNA strings whose parenthesis marks balance.	Hard8	Dynamic programmingString+1	No attempts yet	1s	128 MB	Judgeable
TripleCount distinct triples of grid pairs drawn from three rectangles after discarding repeated pairs and cancelling opposite orderings.	Hard8	CombinatoricsMath	No attempts yet	2s	1024 MB	Judgeable
Light SwitchesDecide whether bulb b is on just after time t when each bulb toggles at times dividing its position and every bulb resets to off at time N.	Hard8	Number theoryMath	No attempts yet	5s	128 MB	Judgeable
AssimilationTwo players alternately flip one connected region of the rival color on a board of up to 5 by 5, and the player whose color fills the board wins.	Hard8	Game theoryGraph+1	No attempts yet	1s	128 MB	Judgeable
Manifest DestinySimulate turn-by-turn movement, eating, combat, and starvation on a grid, and report each group's size, position, and death year.	Hard8	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
PolarizationOrient every edge of the given tree and report the smallest and largest possible numbers of town pairs connected by a directed path.	Hard8	TreeDynamic programming+1	No attempts yet	3s	512 MB	Judgeable
ByteocircleFind the largest fastest-route travel time between any two cities in a wheel network with a central capital and a rim cycle.	Hard8	Shortest pathGraph+2	No attempts yet	1s	128 MB	Judgeable
Euler's ProblemGiven n, list every x with Euler phi(x) equal to n in increasing order, or report none.	Hard8	Number theoryBacktracking+1	No attempts yet	1s	128 MB	Judgeable
PebblesDecide whether the first player wins a take-away game where each move removes a new amount and the opening move cannot take the whole pile.	Hard8	Game theoryMath	No attempts yet	1s	128 MB	Judgeable
HistogramsGiven histogram H and point set S, build a valid histogram from S points that minimizes diffcount or abserror against H.	Hard8	Dynamic programmingPrefix sum	No attempts yet	1s	256 MB	Judgeable
BridgesTowns on two banks link east on the north side and west on the south side while bridges are added and roads close and queries ask if one town reaches another.	Hard8	GraphIntervals+1	No attempts yet	1s	256 MB	Judgeable
Sugar GliderStarting partway up tree 1, climb trees and glide between them while losing one meter of height per glide second to reach the top of tree N in minimum time.	Hard8	Shortest pathHeap	No attempts yet	2s	256 MB	Judgeable
BlocksMove adjacent block pairs into empty cells in the fewest moves to gather N A's and N B's into separate consecutive groups.	Hard8	SimulationGreedy+1	No attempts yet	1s	128 MB	Judgeable
Buffed BuffetFill a plate of weight exactly w from discrete pieces and divisible dishes with linearly fading tastiness to maximize total tastiness.	Hard8	Dynamic programmingBinary search+2	No attempts yet	4s	128 MB	Judgeable
Winning StrategyFor every start and goal pair, find the fewest rounds in which the chooser can force the token to the goal while the opponent picks inside each offered set.	Hard8	Game theoryGraph+1	No attempts yet	8s	128 MB	Judgeable
Maze reductionGroup rooms an explorer cannot tell apart from corridor counts and clockwise exit orders and print each group of at least two.	Hard8	GraphHash map+1	No attempts yet	2s	128 MB	Judgeable
Metal Processing PlantSplit all shipments into two groups so the sum of the largest pairwise distance inside each group is as small as possible.	Hard8	GraphUnion-find+1	No attempts yet	4s	128 MB	Judgeable
PachinkoA ball wanders a grid with random moves and absorbing targets, and each target needs its hit probability from a uniform top-row start.	Hard8	ProbabilityGraph+1	No attempts yet	6s	512 MB	Judgeable
Sensor NetworkFind the largest group of sensors where every pair lies within distance d and print its size and members.	Hard8	BacktrackingGraph+1	No attempts yet	2s	128 MB	Judgeable
Eunki's DNA MoleculesFor every pair of N DNA strings, decide whether four two-way substring swaps can rewrite one into the other.	Hard8	MathString+1	No attempts yet	5s	256 MB	Judgeable
Beads and WiresYou choose append and insert orders that build the given weighted tree to maximize the total length of insert-created edges.	Hard8	Dynamic programmingTree+2	No attempts yet	1s	128 MB	Judgeable
WallApply k range raise-to-at-least and lower-to-at-most updates on n columns and print each final height.	Hard8	Segment tree	No attempts yet	3s	256 MB	Judgeable
GameGiven the pair query order, the program prints the smallest 0/1 answer string that keeps connectivity undecided until the last query.	Hard8	GraphGreedy+1	No attempts yet	1s	512 MB	Judgeable
Agent 007A pursuer enters T turns late and chases a visible foe who wins by holding one of two adjacent servers a full turn; find the largest T with a guaranteed stop.	Hard8	Game theoryShortest path+1	No attempts yet	1s	512 MB	Judgeable
The WallFind the cheapest closed walk along grid lines through the upper-left corner that separates every village cell from the outside of the grid.	Hard8	Shortest pathGraph	No attempts yet	2s	1024 MB	Judgeable
SnakeReconstruct the Hamiltonian path numbering of a 3 by n board from some given cell numbers.	Hard8	BacktrackingGraph+1	No attempts yet	3s	512 MB	Judgeable
CardsThe program decides after each swap of two two-sided cards whether one face per card can show numbers that never decrease left to right.	Hard8	Segment treeDynamic programming	No attempts yet	3s	256 MB	Judgeable
CriminalsFind every house where two given color sequences appear as subsequences on the left and right with both walkers sharing one home color outside.	Hard8	String matchingGreedy+1	No attempts yet	2s	256 MB	Judgeable
SupercomputerGiven a rooted tree of unit-time tasks and many processor counts, compute the fastest finishing time for each count.	Hard8	TreePrefix sum+2	No attempts yet	2s	256 MB	Judgeable
RallyFind the vertex whose removal minimizes the longest directed path in a DAG and report that minimum length.	Hard8	Topological sortDynamic programming+1	No attempts yet	1s	256 MB	Judgeable
Tourist Information PointsChoose minimum-cost towns so every town holds a point or borders one.	Hard8	Dynamic programmingGraph	No attempts yet	1s	256 MB	Judgeable
VialsPour vials in the given order, react each mixed pair to exhaustion in priority order, and total the sediment formed.	Hard8	Union-findSimulation+2	No attempts yet	3s	256 MB	Judgeable
TribesRepeatedly merge axis-aligned rectangles whose overlap has positive area into their bounding box, then print the remaining boxes in lexicographic order.	Hard8	Union-findSegment tree+2	No attempts yet	3s	1024 MB	Judgeable
Persuading the AdvisersTwo rivals take turns claiming undecided experts for opposite sides, and the first asks whether he can force the majority-vote tree to favor him.	Hard8	Game theoryTree+2	No attempts yet	1s	256 MB	Judgeable
Doubling gameGiven a binary grid, compute for each cell the largest token pile reachable by repeatedly merging equal adjacent piles.	Hard8	Dynamic programmingBFS+1	No attempts yet	10s	256 MB	Judgeable
The kingdomFollow the fixed DFS, vertex-split, and Euler-circuit steps to output edge-disjoint even-length trails pairing every odd-degree vertex.	Hard8	GraphDFS+2	No attempts yet	1s	256 MB	Judgeable
Recovering the PopulationsGiven a tree and the distance-weighted sums at each node, recover the node weights that produce them.	Hard8	TreeDFS+1	No attempts yet	4s	256 MB	Judgeable
Self-Describing SequencesCount length-N sequences where each entry A[i] equals the number of times i appears in the sequence.	Hard8	MathCombinatorics+1	No attempts yet	1s	256 MB	Judgeable
Test Data AnalysisCount bounded arrays of length N whose maximum contiguous subarray sum equals D, modulo 1,000,000,007.	Hard8	Dynamic programmingPrefix sum+1	No attempts yet	2s	256 MB	Judgeable
FertilizingEach day the C_i shortest of N trees grow by the day number and the K_i-th shortest height is recorded; report the sum over all days.	Hard8	Segment treeSorting+1	No attempts yet	3s	256 MB	Judgeable
SaveitDesign encode and decode procedures that compress the all-pairs hub distances of a connected graph into a short bitstream, with decode reconstructing every hub-to-city hop count.	Hard8	GraphBFS+2	No attempts yet	2s	256 MB	Judgeable
A Die MakerRoll a die on a board so each move increments the face that lands down, and print the dictionary-smallest move string that reaches the six target numbers.	Hard8	BFSGreedy+2	No attempts yet	8s	256 MB	Judgeable
CheatsCount the completion orders of a tree of prerequisites when up to k parent edges can be skipped to grandparents, with no two skipped edges adjacent.	Hard8	Dynamic programmingTree+1	No attempts yet	10s	256 MB	Judgeable
Fantastic ProblemYou count size-k windows where some pair shares a factor, refresh the count after each point update, then print the final sum.	Hard8	Segment treeNumber theory+1	No attempts yet	10s	256 MB	Judgeable
Gold BanditsThe bandits rob the richest set of villages along a shortest road from home to the castle that still leaves a return route avoiding robbed villages.	Hard8	Shortest pathGraph	No attempts yet	5s	256 MB	Judgeable
Super Mario 169Choose the switch order and the coin pickup routes in 3D so Mario collects every coin with the least total swim distance.	Hard8	Dynamic programmingGeometry+1	No attempts yet	3s	256 MB	Judgeable
Particle SwappingFor each queried start pair, swap two tokens along graph edges one move at a time so their closest approach stays as large as possible.	Hard8	Minimum spanning treeGraph+2	No attempts yet	5s	256 MB	Judgeable
Floor PaintingFind the side length of the largest axis-aligned square that fits inside a given orthogonal simple polygon.	Hard8	GeometryBinary search	No attempts yet	2s	256 MB	Judgeable
PawnsDecide whether White or Black wins a pawn race where each side moves only its own pawns forward until every column is blocked.	Hard8	Game theoryDynamic programming	No attempts yet	1s	256 MB	Judgeable
Lengthy Traveling SalesmanArrange every vertex of a tree into a tour that maximizes the total walked distance and return the lexicographically smallest among the longest tours.	Hard8	TreeGreedy	No attempts yet	1s	256 MB	Judgeable
Sweet WarTwo players alternate passing at one energy each or eating the next ball for its nutrition and taste, and each maximizes total taste eaten.	Hard8	Game theoryDynamic programming	No attempts yet	1s	256 MB	Judgeable
L∞ JumpsMake exactly n jumps of L-infinity length d from (0,0) to (s,t), minimizing total cost where each jump's direction is ranked from a given offset.	Hard8	Divide and conquerGeometry+2	No attempts yet	3s	256 MB	Judgeable
The Leprechaun HuntVillagers and a leprechaun take turns moving on a small graph, and each case asks for the fewest turns that guarantee a capture, or NEVER.	Hard8	Game theoryGraph+1	No attempts yet	3s	256 MB	Judgeable
Shrine MaintenanceSplit the shrines on a circle of radius 1000 among W workers leaving from the center so the longest round trip is as short as possible.	Hard8	Dynamic programmingGeometry+1	No attempts yet	2s	256 MB	Judgeable
Multi-Machine Scheduling of Two ApplicationsEllie assigns the ordered steps of two applications to M machines with different per-step times to minimize the time the last step finishes.	Hard8	Binary searchGreedy+1	No attempts yet	5s	256 MB	Judgeable
Hari MerdekaChoose a string over priced letters with total cost within the budget to maximize the summed scores of all occurrences of the given words.	Hard8	Dynamic programmingString matching	No attempts yet	3s	256 MB	Judgeable
Marbles in a CircleGiven a ring of red, white, and green marbles with a neighbor rule, compute how many marbles of each color remain after N steps.	Hard8	Number theoryMath+2	No attempts yet	1s	256 MB	Judgeable
InspectorsPartition all factories into groups of at least two so the total length of the shortest closed tour of each group is minimized.	Hard8	GraphCombinatorics	No attempts yet	3s	256 MB	Judgeable
Watch, Man!Decide whether guards cover each art piece at its required level when segment and arc walls block sight lines.	Hard8	GraphGeometry	No attempts yet	1s	256 MB	Judgeable
Galaxy collisionYou split the points into two groups whose internal distances exceed 5 and minimize the smaller group.	Hard8	GraphBFS+2	No attempts yet	3s	256 MB	Judgeable
Journey through the kingdomFind the cheapest carriage-hopping cost between consecutive target cells on a grid where each cell rents a ride to any cell in its rectangle range.	Hard8	Shortest pathSegment tree	No attempts yet	3s	256 MB	Judgeable
Knights of the Round TableCount distinct final seat assignments over all entry orders when each remaining knight walks clockwise to the first free seat, modulo 1e9+7.	Hard8	CombinatoricsMath	No attempts yet	3s	256 MB	Judgeable
Farey Sequence SumGiven N, compute the sum of consecutive denominator ratios in the N-th Farey sequence and print it as a reduced fraction.	Hard8	Number theoryMath	No attempts yet	1s	256 MB	Judgeable
MokiaPoint updates add customers to grid cells and each query asks for the total inside a rectangle using only earlier updates.	Hard8	Divide and conquerSegment tree	No attempts yet	1s	128 MB	Judgeable
MarblesPlace three pairwise disjoint axis-aligned rectangles to maximize red marbles in the first plus blue in the second plus green in the third.	Hard8	GeometryPrefix sum+1	No attempts yet	1s	256 MB	Judgeable
Road RepairFind a tree path with total cost at most C that maximizes total benefit.	Hard8	TreeDivide and conquer+1	No attempts yet	1s	256 MB	Judgeable
String TransformationFind the fewest adjacent swaps turning one balanced a/b string into another with every intermediate string balanced, or output -1 if impossible.	Hard8	TreeStack+1	No attempts yet	1s	256 MB	Judgeable
How Does Your Garden Grow?Place up to 50 one-metre plants on a 10 cm grid so the squared gap between each plant water need and the sprinkler water its interval collects is minimal.	Hard8	Dynamic programmingMath+1	No attempts yet	30s	256 MB	Judgeable
Line SweepFind the tallest vertical broom that still reaches every empty cell by sliding sideways, then the fewest sideways sweeps that clean them all.	Hard8	GreedyIntervals+2	No attempts yet	10s	256 MB	Judgeable
ShotcubeSlide runs of cubes with edge shots until blocked and gather all nine into any 3x3 square in the fewest shots.	Hard8	BFSGraph+1	No attempts yet	10s	256 MB	Judgeable
Out of contextFor each text line, print the longest substring the given grammar generates, breaking ties by earliest position, or NONE.	Hard8	Dynamic programmingString matching	No attempts yet	10s	256 MB	Judgeable
ParadesPick the most parade routes between pairs of junctions in a tree so no street is shared by two parades.	Hard8	Dynamic programmingTree+1	No attempts yet	3s	256 MB	Judgeable
Mountainous landscapeFor each segment of a left-to-right polygonal chain, find the nearest later segment with a point strictly above the ray extending the segment.	Hard8	GeometryStack	No attempts yet	10s	256 MB	Judgeable
Virus synthesisBuild each DNA string over A, C, G, and T from empty using single-letter attachments or mirrored duplication in the fewest operations.	Hard8	Dynamic programmingString matching	No attempts yet	20s	256 MB	Judgeable
The ImpPick boxes in some order while an adversary voids up to k of them, and maximize the kept item value minus all purchase costs under optimal play.	Hard8	Game theoryDynamic programming+1	No attempts yet	15s	256 MB	Judgeable
Around the TrackFind the shortest closed route that stays between two nested polygons and winds once around the inner one.	Hard8	GeometryShortest path+1	No attempts yet	2s	256 MB	Judgeable
Money TransfersFind the largest per-edge surcharge F so the cheapest X to Y path using only SWERC banks stays strictly cheaper than any path that visits an outside bank.	Hard8	Shortest pathGraph+1	No attempts yet	1s	256 MB	Judgeable
Volunteer CampStarting from each house in a weighted tree, find the shortest truck route that visits K marked houses without driving back.	Hard8	TreeDynamic programming+1	No attempts yet	2s	128 MB	Judgeable
Enchanted ForestGiven initial heights and growth rates on an N by N grid, find the largest edge-connected group sharing one height at some present or future real time.	Hard8	Union-findSorting+1	No attempts yet	2s	128 MB	Judgeable
Norma's array price sumSum min times max times length over all contiguous subarrays and print the result modulo 1000000000.	Hard8	Divide and conquerStack	No attempts yet	3s	64 MB	Judgeable
Truck EncountersCount how many times each queried pair of trucks, moving at equal speed along zigzag city routes, occupy the same position.	Hard8	IntervalsSorting+1	No attempts yet	3s	64 MB	Judgeable
Transmutation CirclesFind the activation order of nested circles that maximizes total energy from element flips in already active circles.	Hard8	Dynamic programmingTree+1	No attempts yet	10s	256 MB	Judgeable
ContainmentYou pick a set of grid cells covering all failing cells so the number of boundary faces is as small as possible.	Hard8	GraphGeometry	No attempts yet	20s	256 MB	Judgeable
Integer GamePlayers alternately remove a number with no larger remaining neighbor from a row permutation, and whoever takes 1 wins, so decide the winner under optimal play.	Hard8	Game theoryDynamic programming	No attempts yet	5s	256 MB	Judgeable
Stamp StampFind the fewest inked cells in a stamp whose two unrotated presses produce the given paper.	Hard8	Dynamic programmingGraph+2	No attempts yet	10s	256 MB	Judgeable
Cactus GeneratorParse the SCGL definition, build the cactus it describes with merged vertices renumbered, and print the counts, path cover number, and sorted edges.	Hard8	GraphUnion-find+2	No attempts yet	1s	256 MB	Judgeable
Damage AssessmentCompute the remaining gasoline volume in a tilted cylindrical tank with spherical caps from the tilt and liquid level.	Hard8	GeometryMath	No attempts yet	1s	256 MB	Judgeable
ImprovementsReposition ships on a line from a station so no two ropes joining consecutive ships cross, keeping as many ships as possible in place.	Hard8	Dynamic programmingCombinatorics+1	No attempts yet	1s	256 MB	Judgeable
Line Fitting Under UncertaintyFind the line that minimizes the worst expected absolute deviation from uncertain sample values and print that error.	Hard8	Binary searchGeometry+1	No attempts yet	2s	256 MB	Judgeable
Polygon GuardsPlace the fewest guards on vertices of an orthogonal simple polygon with under 40 vertices so every vertex is visible from a guard.	Hard8	GeometryBrute force+2	No attempts yet	5s	128 MB	Judgeable
Integer in IntegerCount how many times C appears as a (possibly overlapping) substring in the decimal writings of all integers from A to B, modulo 1000000007.	Hard8	Dynamic programmingString matching+1	No attempts yet	10s	128 MB	Judgeable
Molecule Pair Distance HistogramFrom molecule counts on an N by N grid, find the mean pairwise Euclidean distance and the count of pairs at each squared distance.	Hard8	Divide and conquerMatrix+2	No attempts yet	10s	512 MB	Judgeable