Problems

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Total results29,335 problems

How to Create a Good Game
Hard8
Graph, Dynamic programming+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Cruel Bingo
Hard8
Combinatorics, Dynamic programming+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Ika Number
Hard8
Combinatorics, Dynamic programming+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Carrot breeding
Hard8
Geometry, Combinatorics
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Bubble Puzzle
Hard8
BFS, Simulation+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Shelter
Hard8
Geometry, Divide and conquer+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Nezumi's Treasure
Hard8
Geometry, Simulation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Shore Erosion
Hard8
Geometry, Implementation
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Magic Slayer
Hard8
Dynamic programming, Greedy+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Voronoi Island
Hard8
Geometry, Divide and conquer+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Revenge of the Round Table
Hard8
Combinatorics, Math+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Luigi's Tavern
Hard8
Graph, Dynamic programming+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Colored Octahedra
Hard8
Combinatorics, Math+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Wind Passages
Hard8
Geometry, Graph+1
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Adhoc Translation
Hard8
Dynamic programming, String+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Cover Time
Hard8
Dynamic programming, Probability+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Craftsman
Hard8
Dynamic programming, Bit manipulation+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Divide the Water
Hard8
Tree, Greedy+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Mickle's Beam
Hard8
Geometry, Greedy+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Poor Computer
Hard8
Brute force, Dynamic programming+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Tangram
Hard8
Backtracking, Geometry+1
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Trading Ship
Hard8
Binary search, Graph+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Princess' Marriage
Hard8
Greedy, Sorting+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Princess, a Cryptanalyst
Hard8
Dynamic programming, Bit manipulation+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Princess, a Strategist
Hard8
Geometry, Simulation
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Time Trial
Hard8
BFS, Graph+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Memory Match
Hard8
Probability, Dynamic programming+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Girls' Party
Hard8
Simulation, Brute force+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Ninja Legend
Hard8
Shortest path, Bit manipulation+1
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Do It
Hard8
Math, Divide and conquer+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Robot Communication
Hard8
Minimum spanning tree, Geometry+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Compress Files
Hard8
Dynamic programming, Bit manipulation+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Save the Energy
Hard8
Geometry, Graph+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
!
Hard8
Number theory, Math+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Spirograph
Hard8
Math, Geometry+1
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Petoris
Hard8
Brute force, Implementation+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Nagashi Soumen
Hard8
Dynamic programming, Geometry+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Median Filter
Hard8
Brute force, Backtracking+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Connect Line Segments
Hard8
Dynamic programming, Bit manipulation+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Divisor Function
Hard8
Number theory, Math+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Two Rings
Hard8
Geometry, Math+1
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Billion Million Thousand
Hard8
Dynamic programming, String+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
The Closest Circle
Hard8
Divide and conquer, Geometry+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Rakunarok
Hard8
Shortest path, Dynamic programming+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Flame of Nucleus
Hard8
Graph, Shortest path+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Poor Mail Forwarding
Hard8
Simulation, Shortest path+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Ellipse Intersection
Hard8
Math, Geometry+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Colors
Hard8
Graph, DFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
A Treasure Or A Bomb
Hard8
Dynamic programming, Math+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Up and Down
Hard8
Dynamic programming, Backtracking+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Help the Museum
Hard8
BFS, Graph+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Enclosing Circles
Hard8
Geometry, Graph+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Jigsaw Puzzles for Computers
Hard8
Backtracking, Brute force+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Patience
Hard8
Dynamic programming, Bit manipulation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
The Devil of Gravity
Hard8
Simulation, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Numoeba
Hard8
Simulation, Tree+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Trapezoids
Hard8
Implementation, Simulation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Guess the Formula Quiz Game
Hard8
Number theory, Math+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Broken Calculator Game
Hard8
Segment tree, String+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
The Second Rhythm Game of Goinmul
Hard8
Dynamic programming, Two pointers+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Tsubame Gaeshi
Hard8
Brute force, Sorting+2
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
A Simple Problem
Hard8
Sorting, Divide and conquer+2
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Beacon Fire Towers
Hard8
Dynamic programming, Divide and conquer+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Red and Blue
Hard8
Union-find, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
32 MB
Judgeable
Prime Time
Hard8
Dynamic programming, Math+2
No attempts yet
Time limit
45s
Memory limit
1024 MB
Judgeable
Setting Problems for the Orange Cup
Hard8
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Orange Farm Simulation
Hard8
Tree, Trie+2
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Orange Number
Hard8
Math, Number theory+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Orange Leaf's Special Training
Hard8
String matching, Segment tree+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Cutting Cake
Hard8
Geometry, Math+1
No attempts yet
Time limit
45s
Memory limit
1024 MB
Judgeable
Contest Construction
Hard8
Sorting, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Ketek Counting
Hard8
Dynamic programming, String matching
No attempts yet
Time limit
4s
Memory limit
64 MB
Judgeable
Special Cycle
Hard8
Graph, DFS+1
No attempts yet
Time limit
7s
Memory limit
2048 MB
Judgeable
The King's Guards
Hard8
Graph, Minimum spanning tree+1
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
TraveLog
Hard8
Graph, Shortest path+2
No attempts yet
Time limit
4s
Memory limit
2048 MB
Judgeable
Weekly Calendar
Hard8
Sliding window, Prefix sum+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Deadly Rain
Hard8
BFS, Bit manipulation+1
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Graph Tree Partition
Hard8
Graph, DFS+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Shower
Hard8
Union-find, Simulation+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
k Subarrays
Hard8
Array, Sorting+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Terror
Hard8
Backtracking, Recursion+2
No attempts yet
Time limit
2.5s
Memory limit
1024 MB
Judgeable
Calculator Optimization
Hard8
Segment tree, Matrix+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
The Snail Wants to Rest in the Shade
Hard8
Geometry, Sorting+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Dakku (Diary Decorating)
Hard8
Segment tree, Matrix+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Number of Increasing Subsequences K
Hard8
Combinatorics, Dynamic programming+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Truck Delivery
Hard8
Tree, DFS+2
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Primes and Queries
Hard8
Number theory, Segment tree+2
No attempts yet
Time limit
90s
Memory limit
1024 MB
Judgeable
Hiking Trails
Hard8
Dynamic programming, Bit manipulation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Homework
Hard8
Greedy, Sorting+1
No attempts yet
Time limit
1.5s
Memory limit
512 MB
Judgeable
Stop the Group Project!
Hard8
Minimum spanning tree, Graph+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Leaping Pieces
Hard8
Math, Number theory+2
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Sculpting a Tree
Hard8
Tree, Binary search+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Kyojun Stargazing
Hard8
Geometry, Combinatorics+2
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Nutella Tree
Hard8
Tree, Segment tree
No attempts yet
Time limit
7s
Memory limit
1024 MB
Judgeable
Newspapers
Hard8
Graph, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Stones
Hard8
Game theory, Greedy+2
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Uuu
Hard8
Union-find, Graph+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Graph Travel
Hard8
Graph, Dynamic programming+2
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Splitting into Two Classes
Hard8
Union-find, Graph+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Shortest Shortest Path
Hard8
Graph, Shortest path+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
How to Create a Good GameA DAG with weighted edges has each edge weight increased as much as possible without raising the longest path from node 0 to node N-1. Output the total added weight.	Hard8	GraphDynamic programming+2	No attempts yet	8s	512 MB	Judgeable
Cruel BingoGiven up to 8 pre-marked cells on an N by N bingo card, count the ways to reach exactly N unmarked cells while avoiding any full row, column, or diagonal, modulo 10007.	Hard8	CombinatoricsDynamic programming+2	No attempts yet	8s	512 MB	Judgeable
Ika NumberFind the K-th smallest positive integer that counts squid paths from one point to another (jumps of 1 or 2) while avoiding a forbidden integer coordinate.	Hard8	CombinatoricsDynamic programming+2	No attempts yet	8s	512 MB	Judgeable
Carrot breedingPlace the fewest lattice points in the square so that each point lies on exactly N lines through at least two points, or report -1 if impossible.	Hard8	GeometryCombinatorics	No attempts yet	8s	512 MB	Judgeable
Bubble PuzzleGiven a 4x4 grid of bubble states, find the minimum clicks to clear every bubble, with chain reactions from flying waterdrops, or -1 if more than 5.	Hard8	BFSSimulation+2	No attempts yet	8s	512 MB	Judgeable
ShelterGiven a convex polygon town and N interior shelters, compute the expected squared distance from a uniformly random point in the town to its nearest shelter.	Hard8	GeometryDivide and conquer+2	No attempts yet	8s	512 MB	Judgeable
Nezumi's TreasureCount the points where a mouse that turns left at each rectangle obstacle could hide his fish at the first turn after entering an infinite loop.	Hard8	GeometrySimulation+2	No attempts yet	2s	512 MB	Judgeable
Shore ErosionGiven a counterclockwise polygon and erosion distance R, find the total boundary length left after removing points within Manhattan distance R of the coast.	Hard8	GeometryImplementation	No attempts yet	8s	512 MB	Judgeable
Magic SlayerGiven N monsters with hit points and M spells that damage one or all monsters at some power cost, find the minimum total power to defeat every monster.	Hard8	Dynamic programmingGreedy+2	No attempts yet	8s	512 MB	Judgeable
Voronoi IslandFor each dataset, divide a convex island polygon among M castles by nearest-castle rule and print each lord's resulting area within 1e-4.	Hard8	GeometryDivide and conquer+2	No attempts yet	8s	512 MB	Judgeable
Revenge of the Round TableCount circular binary sequences of length n with no run of more than k equal symbols, modulo 1000003, up to rotation.	Hard8	CombinatoricsMath+2	No attempts yet	8s	512 MB	Judgeable
Luigi's TavernGiven counts of heroes, warriors, clerics, and mages plus pairwise compatibility lists along a hero-warrior-cleric-mage chain, find the maximum number of valid parties under limits on how many may skip a role.	Hard8	GraphDynamic programming+2	No attempts yet	8s	512 MB	Judgeable
Colored OctahedraCount how many distinct octahedra can be formed from eight colored triangular panels, treating two octahedra as identical when a rotation maps one to the other.	Hard8	CombinatoricsMath+2	No attempts yet	8s	512 MB	Judgeable
Wind PassagesGiven a corridor of width W with non-overlapping polygonal pillars, find the maximum flow from south to north where each path's capacity is its narrowest gap.	Hard8	GeometryGraph+1	No attempts yet	8s	512 MB	Judgeable
Adhoc TranslationGiven text words and dictionary words, assign each distinct text word a unique dictionary word, minimizing the total edit distance summed over all occurrences.	Hard8	Dynamic programmingString+2	No attempts yet	8s	512 MB	Judgeable
Cover TimeCompute the expected number of steps for a random walk starting at vertex 1 to visit every vertex of a connected undirected graph with N at most 10.	Hard8	Dynamic programmingProbability+2	No attempts yet	8s	512 MB	Judgeable
CraftsmanChoose which orders to accept and which tools to buy, where discounted tool pairs bought together change the cost, to maximize income minus tool cost.	Hard8	Dynamic programmingBit manipulation+2	No attempts yet	8s	512 MB	Judgeable
Divide the WaterGiven the target integer proportions of N ordered columns, find the minimum number of faucets (each splitting into halves via binary tubes) whose flow, laid out without crossing, realizes those proportions.	Hard8	TreeGreedy+2	No attempts yet	8s	512 MB	Judgeable
Mickle's BeamGiven up to 2000 disjoint axis-aligned rectangles that avoid the origin, find the minimum number of rays from the origin needed to hit every rectangle.	Hard8	GeometryGreedy+2	No attempts yet	8s	512 MB	Judgeable
Poor ComputerGiven distinct multipliers between 2 and 42, find the shortest sequence of additions, subtractions, and left shifts that builds all values a_i*x from x without exceeding 42x.	Hard8	Brute forceDynamic programming+2	No attempts yet	8s	512 MB	Judgeable
TangramGiven a simple polygon whose edges run horizontally, vertically, or diagonally, decide whether all seven tangram pieces can tile it without overlap.	Hard8	BacktrackingGeometry+1	No attempts yet	8s	512 MB	Judgeable
Trading ShipFind a path from the bottom edge y=0 to the top edge y=H inside a rectangle that maximizes the minimum distance to any of N given points.	Hard8	Binary searchGraph+2	No attempts yet	8s	512 MB	Judgeable
Princess' MarriageWith budget M, choose how much of each road segment to guard (cost 1 per unit, reducing attacks proportionally) to minimize the total expected number of attacks along the route.	Hard8	GreedySorting+2	No attempts yet	8s	512 MB	Judgeable
Princess, a CryptanalystGiven up to 10 short words, find the shortest string that contains every word as a substring, breaking ties by lexicographic order.	Hard8	Dynamic programmingBit manipulation+2	No attempts yet	8s	512 MB	Judgeable
Princess, a StrategistGiven a moving polygon and bullet segments that travel with their own velocities, report every time a bullet first touches the polygon.	Hard8	GeometrySimulation	No attempts yet	8s	512 MB	Judgeable
Time TrialGiven a grid with a hero, three rocks, and three marked squares, find the minimum number of steps to push all rocks onto the marks, where the hero can only push one rock at a time.	Hard8	BFSGraph+2	No attempts yet	8s	512 MB	Judgeable
Memory MatchWith perfect memory of every card seen, compute the expected number of mismatches when playing memory match optimally on 2M cards.	Hard8	ProbabilityDynamic programming+2	No attempts yet	8s	512 MB	Judgeable
Girls' PartyIn a Josephus-style elimination game on a circular string of B and G girls, Bella may switch the count start from 1 to 0 at most once; find the maximum number of B girls that can survive at the end.	Hard8	SimulationBrute force+2	No attempts yet	8s	512 MB	Judgeable
Ninja LegendFind the maximum number of gold blocks a ninja can collect in a grid mansion with pitfalls, and the minimum moves needed to collect them.	Hard8	Shortest pathBit manipulation+1	No attempts yet	8s	512 MB	Judgeable
Do ItIntegrate a product of N sine functions over [0, R], with N up to 16, to absolute or relative error 1e-8.	Hard8	MathDivide and conquer+2	No attempts yet	8s	512 MB	Judgeable
Robot CommunicationRobots move linearly on a plane over time; choose a single moment and a connected communication graph to minimize the total distance of its edges.	Hard8	Minimum spanning treeGeometry+2	No attempts yet	8s	512 MB	Judgeable
Compress FilesGiven n files with uncompressed and compressed sizes and a disk with m free space, find the minimum number of archives reachable through repeated group-compress-delete steps.	Hard8	Dynamic programmingBit manipulation+2	No attempts yet	8s	512 MB	Judgeable
Save the EnergyGiven N infinite straight lines in 3D, find the minimum off-line distance needed to travel from a source point on some line to a destination point on some line, where travel along lines is free.	Hard8	GeometryGraph+2	No attempts yet	8s	512 MB	Judgeable
!For each pair of a base N (8 to 36) and a number M written in base N, output how many trailing zeros M! has when written in base N.	Hard8	Number theoryMath+2	No attempts yet	8s	512 MB	Judgeable
SpirographFor each test case, compute the total arc length of a hypotrochoid traced by a pinhole in a circle of radius Q rolling inside a fixed circle of radius P, with pinhole offset R.	Hard8	MathGeometry+1	No attempts yet	8s	512 MB	Judgeable
PetorisPlace a rotatable, non-flippable polyomino block on a board without overlap, maximizing fully filled horizontal lines, or discard it for -1.	Hard8	Brute forceImplementation+2	No attempts yet	8s	512 MB	Judgeable
Nagashi SoumenGiven N points in space and at most K strictly descending flumes (paths whose z-coordinate decreases), find the minimum total length of flumes that cover every point.	Hard8	Dynamic programmingGeometry+2	No attempts yet	8s	512 MB	Judgeable
Median FilterGiven a 3x3 median-filtered black-and-white image, find the maximum and minimum possible counts of black pixels in any original image and report their difference, or Impossible.	Hard8	Brute forceBacktracking+2	No attempts yet	8s	512 MB	Judgeable
Connect Line SegmentsGiven up to 14 line segments, add connecting segments between endpoints to join all of them into one polyline of minimum total length.	Hard8	Dynamic programmingBit manipulation+2	No attempts yet	8s	512 MB	Judgeable
Divisor FunctionFor each k up to 10^15, find the maximum value of sigma(n)/n over all n from 1 to k, printed to six decimals.	Hard8	Number theoryMath+2	No attempts yet	8s	512 MB	Judgeable
Two RingsGiven two circles on the unit sphere, each defined by two latitude/longitude endpoints, find and print their intersection points or report that none exist.	Hard8	GeometryMath+1	No attempts yet	8s	512 MB	Judgeable
Billion Million ThousandGiven dictionary words for powers of ten, parse an unseparated Usoperant numeral as the largest possible number and find the shortest separated expression with the same value.	Hard8	Dynamic programmingString+2	No attempts yet	8s	512 MB	Judgeable
The Closest CircleGiven up to 100000 non-overlapping circles whose radii differ by at most a factor of two, find the pair of circles with the smallest gap between them and print that distance.	Hard8	Divide and conquerGeometry+2	No attempts yet	8s	512 MB	Judgeable
RakunarokGiven a weighted undirected graph with experience and time on each road, find a path from s to t whose towns strictly decrease in shortest-time distance to t and whose total experience divided by total time is maximal.	Hard8	Shortest pathDynamic programming+2	No attempts yet	8s	512 MB	Judgeable
Flame of NucleusGiven a weighted undirected graph with citizens and shelter capacities at each node, find the maximum number who can reach a shelter in fewer than L days.	Hard8	GraphShortest path+2	No attempts yet	8s	512 MB	Judgeable
Poor Mail ForwardingSimulate mail moving through a post office network where each office has one courier; find each piece's arrival time at its destination.	Hard8	SimulationShortest path+2	No attempts yet	8s	512 MB	Judgeable
Ellipse IntersectionGiven two concentric axis-aligned ellipses with perpendicular major axes, compute the area of their intersection to within 0.001.	Hard8	MathGeometry+2	No attempts yet	8s	512 MB	Judgeable
ColorsGiven a robot blueprint that builds a graph by adding nodes on tracks, linking active components, and merging modules, decide whether the resulting toy graph is 3-colorable.	Hard8	GraphDFS+2	No attempts yet	2s	512 MB	Judgeable
A Treasure Or A BombAssign each key to a distinct keyhole to maximize the product of (1 - p_ij), printing the chosen key per keyhole; N up to 100, multiple test cases.	Hard8	Dynamic programmingMath+2	No attempts yet	8s	512 MB	Judgeable
Up and DownCount permutations of 1..N whose up-sequence and down-sequence (nearest larger/smaller distance to the right) match the given arrays; N is at most 17.	Hard8	Dynamic programmingBacktracking+2	No attempts yet	8s	512 MB	Judgeable
Help the MuseumGiven a grid of artist letters, find the shortest left-to-right path using cells of one chosen artist, optionally swapping two cells first, and print the path coordinates.	Hard8	BFSGraph+2	No attempts yet	8s	512 MB	Judgeable
Enclosing CirclesGiven up to 100 circles that may overlap or nest, find the shortest rope that encloses them all, allowing straight segments and arcs along circle boundaries.	Hard8	GeometryGraph+2	No attempts yet	2s	512 MB	Judgeable
Jigsaw Puzzles for ComputersCount the ways to arrange nine given square pieces in a 3x3 grid, rotating each freely, so that every touching pair of edges matches as an uppercase and lowercase pair.	Hard8	BacktrackingBrute force+2	No attempts yet	2s	512 MB	Judgeable
PatienceGiven twenty cards in a 5 by 4 grid, repeatedly remove an adjacent equal pair and compact the survivors, choosing pairs to minimize the cards left.	Hard8	Dynamic programmingBit manipulation+2	No attempts yet	2s	512 MB	Judgeable
The Devil of GravitySimulate a 2D editor where text segments fall under gravity and merge when adjacent, then report the current segment or ERROR after a command sequence.	Hard8	SimulationImplementation+1	No attempts yet	2s	512 MB	Judgeable
NumoebaSimulate a tree of cells whose odd values evolve under a 3n+1 rule, with deaths, bonus spawns, and leader changes, then report lifetime and peak population.	Hard8	SimulationTree+2	No attempts yet	2s	512 MB	Judgeable
TrapezoidsGiven an ASCII picture made of asterisks, find all trapezoids whose sides are horizontal and vertical or 45-degree lines, and report counts of trapezoids grouped by area.	Hard8	ImplementationSimulation+2	No attempts yet	2s	512 MB	Judgeable
Guess the Formula Quiz GameGiven f(x) mod p for x = 1 to p-1, recover the coefficients a_1 to a_(p-1) in the range 0 to p-1 of f(x) = sum of a_i * i^x mod p.	Hard8	Number theoryMath+1	No attempts yet	3s	1024 MB	Judgeable
Broken Calculator GameGiven a formula of digits and operators, apply Q range additions mod 12 to its characters and report the evaluated value after each update.	Hard8	Segment treeString+1	No attempts yet	4s	1024 MB	Judgeable
The Second Rhythm Game of GoinmulFor each level with gauge cap X and fever length Y, find the maximum total score when fever time is activated each time the gauge fills.	Hard8	Dynamic programmingTwo pointers+2	No attempts yet	2s	1024 MB	Judgeable
Tsubame GaeshiGiven N weighted points, choose exactly three axis-parallel lines to maximize the total weight of points they cover, counting overlaps once.	Hard8	Brute forceSorting+2	No attempts yet	4s	1024 MB	Judgeable
A Simple ProblemGiven two length-N sequences p and q, compute the sum over all ordered pairs of the smaller of the p-distance and the q-distance. N can reach one million.	Hard8	SortingDivide and conquer+2	No attempts yet	4s	1024 MB	Judgeable
Beacon Fire TowersGiven a permutation of heights 1..N, count the ways to cut the line into consecutive segments so that the segment maxima strictly increase left to right, modulo 1e9+7.	Hard8	Dynamic programmingDivide and conquer+2	No attempts yet	1s	1024 MB	Judgeable
Red and BlueGiven merge, loss, and red-count range observations on bags of marbles, decide if a red/blue coloring fits all entries and print one.	Hard8	Union-findPrefix sum+1	No attempts yet	2s	32 MB	Judgeable
Prime TimeSplit a multiset of prime cards into two nonempty groups so the first group's sum equals the second group's product, maximizing that common value.	Hard8	Dynamic programmingMath+2	No attempts yet	45s	1024 MB	Judgeable
Setting Problems for the Orange CupFor each cap L from 1 to N, choose exactly K problems so that no setter appears more than L times, minimizing total preparation time, or report -1.	Hard8	GreedySorting+2	No attempts yet	1s	1024 MB	Judgeable
Orange Farm SimulationFor each road in a tree of fields, find the largest XOR of competitiveness values between a field on one side and a field on the other side after cutting that road.	Hard8	TreeTrie+2	No attempts yet	10s	1024 MB	Judgeable
Orange NumberGiven K between 1000 and 10000, output three distinct natural numbers N under 100000 digits, not divisible by 10, such that the digit sum of N and of N squared both equal K, or -1 if impossible.	Hard8	MathNumber theory+2	No attempts yet	1s	1024 MB	Judgeable
Orange Leaf's Special TrainingGiven an array and Q queries [l, r], sum the longest common prefix length of [l, r] with every subsegment [i, j] of the array, modulo 1e9+7.	Hard8	String matchingSegment tree+1	No attempts yet	8s	1024 MB	Judgeable
Cutting CakeGiven triangular icing patches on a cake, find the vertical cut that minimizes the absolute gap between the two pieces' enjoyment, reported as an exact fraction.	Hard8	GeometryMath+1	No attempts yet	45s	1024 MB	Judgeable
Contest ConstructionCount k-element subsets of n given difficulties such that, sorted ascending, each element from the third onward is at most the sum of the two before it.	Hard8	SortingDynamic programming+2	No attempts yet	1s	2048 MB	Judgeable
Ketek CountingCount the distinct word-palindrome sentences formed by replacing each '?' with a letter and inserting spaces, modulo 998244353.	Hard8	Dynamic programmingString matching	No attempts yet	4s	64 MB	Judgeable
Special CycleFind any simple cycle where each Special edge either lies on the cycle or has no endpoint on it, or report -1 if no such cycle exists.	Hard8	GraphDFS+1	No attempts yet	7s	2048 MB	Judgeable
The King's GuardsFind the cheapest set of roads to improve so that every village is in a connected group holding exactly one guard, with each guard placed in one of its allowed villages.	Hard8	GraphMinimum spanning tree+1	No attempts yet	1s	2048 MB	Judgeable
TraveLogGiven a weighted digraph and a shuffled set of arrival times from a shortest 1-to-n path, decide whether the path is unique and print it if so.	Hard8	GraphShortest path+2	No attempts yet	4s	2048 MB	Judgeable
Weekly CalendarPlace N consecutive 7-day weeks over a timeline, maximize total covered schedule area, and among ties minimize start date and report the number of tape cuts.	Hard8	Sliding windowPrefix sum+2	No attempts yet	1s	512 MB	Judgeable
Deadly RainFind the fewest moves from S to E on an N by N grid while managing umbrellas with durability and health, where rain hits every cell except S and E.	Hard8	BFSBit manipulation+1	No attempts yet	1.5s	1024 MB	Judgeable
Graph Tree PartitionSplit a graph into two vertex-disjoint trees of different sizes by deleting edges, or report that no such split exists.	Hard8	GraphDFS+2	No attempts yet	2s	1024 MB	Judgeable
ShowerRain lowers cell heights over Q days; after each shower, report the lowest cell in the water-connected region containing the shower cell, breaking ties by the earliest rain time.	Hard8	Union-findSimulation+2	No attempts yet	2s	1024 MB	Judgeable
k SubarraysGiven a permutation of distinct integers, find the smallest k such that repeatedly cutting the array into k contiguous pieces and reordering them can sort it.	Hard8	ArraySorting+2	No attempts yet	1s	1024 MB	Judgeable
TerrorGiven the sorted list of all pairwise distances among N houses on a line, reconstruct the actual positions with the first house fixed at 0.	Hard8	BacktrackingRecursion+2	No attempts yet	2.5s	1024 MB	Judgeable
Calculator OptimizationGiven a sequence of add and multiply operations modulo 1e9+7, process up to 5e5 point updates and after each one output the result of evaluating the whole sequence.	Hard8	Segment treeMatrix+2	No attempts yet	2s	512 MB	Judgeable
The Snail Wants to Rest in the ShadeGiven a rectilinear polygon lit by 45-degree sunlight from the upper right, find the total length of shaded surface where a snail can avoid the sun.	Hard8	GeometrySorting+1	No attempts yet	1s	512 MB	Judgeable
Dakku (Diary Decorating)Given a grid with point updates, each query asks for the largest sum of one contiguous piece of a rectangle's one-cell-thick border.	Hard8	Segment treeMatrix+1	No attempts yet	3s	1024 MB	Judgeable
Number of Increasing Subsequences KGiven K, construct a sequence of at most 34 positive integers that has exactly K increasing subsequences.	Hard8	CombinatoricsDynamic programming+2	No attempts yet	2s	1024 MB	Judgeable
Truck DeliveryFor each query (city C, weight W) on a tree, find the gcd of toll charges on edges from C to the root whose load-limit is at most W, or 0 if none apply.	Hard8	TreeDFS+2	No attempts yet	Not set	1024 MB	Judgeable
Primes and QueriesGiven a prime P, an array A, and point updates, answer range queries summing V(A_i^S - (A_i mod P)^S), where V counts the exponent of P.	Hard8	Number theorySegment tree+2	No attempts yet	90s	1024 MB	Judgeable
Hiking TrailsCount ordered alternating sequences of distinct east and west trails, bridged by x, whose total length falls in [C, D].	Hard8	Dynamic programmingBit manipulation+2	No attempts yet	1s	512 MB	Judgeable
HomeworkSchedule all n assignments, each revealed at time t[i] and incurring penalty (submit time - t[i]) * v[i], with at least 1 unit rest between submissions starting from time S, to minimize total penalty.	Hard8	GreedySorting+1	No attempts yet	1.5s	512 MB	Judgeable
Stop the Group Project!Split N students into two nonempty groups with leaders X and Y, and for each of Q queries find the minimum total contact cost so everyone hears the announcement.	Hard8	Minimum spanning treeGraph+2	No attempts yet	2s	512 MB	Judgeable
Leaping PiecesGiven N and M, find the minimum number of lattice points that must hold presents so that a leaping (N,M)-piece starting anywhere can always reach one of them.	Hard8	MathNumber theory+2	No attempts yet	0.5s	1024 MB	Judgeable
Sculpting a TreeGiven a tree and a set of vertices to remove, place bombs on some vertices so that exactly the marked vertices lie within distance p of a bomb, maximizing p.	Hard8	TreeBinary search+2	No attempts yet	2s	1024 MB	Judgeable
Kyojun StargazingCount the ordered splits of N points into two nonempty labeled groups that a single line, avoiding all points, can separate, modulo 1e9+7.	Hard8	GeometryCombinatorics+2	No attempts yet	1.5s	1024 MB	Judgeable
Nutella TreeCount the simple paths in a tree whose first vertex is black and whose other vertices are all red, and recount after each single color flip.	Hard8	TreeSegment tree	No attempts yet	7s	1024 MB	Judgeable
NewspapersGiven a connected undirected graph, decide whether Ankica can always catch Branko as he moves along edges, and output a shortest guessing sequence if she can.	Hard8	GraphImplementation	No attempts yet	2s	1024 MB	Judgeable
StonesIn this take-away game, each player points to a non-empty pile on their turn and the opponent chooses how many stones to remove; decide whether the first pointer (Ankica) wins.	Hard8	Game theoryGreedy+2	No attempts yet	3s	512 MB	Judgeable
UuuGiven N vertices and M edges, output an undirected simple graph that makes a buggy union-find implementation's inner loop run as many times as possible.	Hard8	Union-findGraph+2	No attempts yet	2s	1024 MB	Judgeable
Graph TravelGiven rooms with point rewards and shields that open only while the running total lies in [L, R], count the distinct orders of first-time room entries that end with exactly K points.	Hard8	GraphDynamic programming+2	No attempts yet	Not set	1024 MB	Judgeable
Splitting into Two ClassesRemove the fewest prefix of a given edge-removal list so the remaining graph becomes bipartite, and report the two sides. The order matters and connectivity of the initial graph is guaranteed.	Hard8	Union-findGraph+2	No attempts yet	1s	1024 MB	Judgeable
Shortest Shortest PathFind a shortest path from x to y that uses the fewest edges, then count how many such paths exist modulo 1e9+9. Multiple parallel edges count as distinct paths.	Hard8	GraphShortest path+2	No attempts yet	2s	1024 MB	Judgeable