Problems

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Total results29,417 problems

Bricks
Hard8
Dynamic programming, Number theory+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Wi-Fi Network
Hard8
Geometry, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Promotion
Hard8
Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hossa (Bull Market)
Hard8
Combinatorics, Recursion
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Autumn Trip
Hard8
Graph, DFS
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Text Algorithms
Hard8
Dynamic programming, String matching
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hey, Better Bettor
Hard8
Probability, Dynamic programming+1
No attempts yet
Time limit
4s
Memory limit
128 MB
Judgeable
Surely You Congest
Hard8
Graph, Shortest path
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Prime Factor Arrangements
Hard8
Combinatorics, Number theory+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Harvard
Hard8
Backtracking, Dynamic programming+1
No attempts yet
Time limit
10s
Memory limit
128 MB
Judgeable
Paper Map
Hard8
Geometry, Brute force
No attempts yet
Time limit
20s
Memory limit
128 MB
Judgeable
Matryoshka Dolls
Hard8
Dynamic programming, Intervals
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Pirate Chest
Hard8
Math, Matrix+1
No attempts yet
Time limit
15s
Memory limit
128 MB
Judgeable
Contour Map
Hard8
Geometry, Sorting+2
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Critical 3-Path
Hard8
Dynamic programming, Graph+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Pandora
Hard8
Geometry, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sports Channel GSK
Hard8
Graph, Sorting
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Block Compaction
Hard8
Simulation, Geometry+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
String Phone
Hard8
Graph, DFS
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Installations
Hard8
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Opening a Restaurant
Hard8
Geometry, Sorting+1
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
KTX Train Depot
Hard8
Greedy, Sorting+1
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Kingdom
Hard8
Union-find, Segment tree+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Jinhan
Hard8
Union-find, Greedy
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Homing
Hard8
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Metal
Hard8
Dynamic programming, Geometry+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Grid Panel
Hard8
Geometry, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Roommate
Hard8
Dynamic programming, Shortest path
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fire Tower
Hard8
Geometry, Binary search
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Depth Order
Hard8
Topological sort, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cycle Game
Hard8
Game theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Intelligent Robots
Hard8
Geometry, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Digital Onion
Hard8
Combinatorics, Recursion+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The K-League
Hard8
Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
A Lazy Worker
Hard8
Dynamic programming, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
PCB
Hard8
Geometry, Binary search
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Castles
Hard8
Geometry, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stains
Hard8
Dynamic programming, Geometry+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sewerage Planning
Hard8
Geometry, Binary search
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Detective Conan
Hard8
Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tree Labeling
Hard8
Tree, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Straightening a bent wire
Hard8
Geometry, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Booksort
Hard8
Backtracking, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Triangle War
Hard8
Game theory, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rotate and Rewrite
Hard8
Dynamic programming, String matching+1
No attempts yet
Time limit
15s
Memory limit
128 MB
Judgeable
Ringworld
Hard8
Greedy, Intervals+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
The King of the North
Hard8
Graph, Matrix
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fragment Reassembly
Hard8
Backtracking, String matching+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fine Dining Restaurant
Hard8
String matching, Trie+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Dance
Hard8
Number theory, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Checkmate with Two Rooks
Hard8
Game theory, BFS+1
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Red John Game
Hard8
Math, Combinatorics
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Series-Parallel Parking Lot
Hard8
Dynamic programming, Tree+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
ZZ
Hard8
Combinatorics, Number theory+1
No attempts yet
Time limit
15s
Memory limit
64 MB
Judgeable
Bribing the Syndicate
Hard8
Dynamic programming, Probability
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Indisputable Right
Hard8
Geometry, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Avaricious ISP
Hard8
Geometry, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tracking Robots
Hard8
Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Correcting Curiosity
Hard8
String matching, String+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Garage
Hard8
Geometry, Math+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Intellectual Property
Hard8
Backtracking, Brute force+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
J
Hard8
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Golf Field
Hard8
Geometry, Two pointers
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Passwords
Hard8
String matching, String
No attempts yet
Time limit
7s
Memory limit
128 MB
Judgeable
String Path
Hard8
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pascal Matrix Power
Hard8
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Beautiful Landscape
Hard8
Dynamic programming, Prefix sum+1
No attempts yet
Time limit
20s
Memory limit
128 MB
Judgeable
Electric Car Rally
Hard8
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tandem Repeats
Hard8
String matching, Divide and conquer
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Leave Your Name
Hard8
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
12s
Memory limit
128 MB
Judgeable
Beautiful Rectangle
Hard8
Graph, Union-find+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Crusher's Code
Hard8
Probability, Dynamic programming+1
No attempts yet
Time limit
10s
Memory limit
128 MB
Judgeable
Janeway's Journey
Hard8
Geometry, Sorting+1
No attempts yet
Time limit
40s
Memory limit
128 MB
Judgeable
Mass Production
Hard8
Graph, Math
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Kkunglish
Hard8
Segment tree, String matching
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Disjoint water supply
Hard8
Graph, Topological sort+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Inverting Huffman
Hard8
Greedy, Tree+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rubik's Rectangle
Hard8
Math, Combinatorics
No attempts yet
Time limit
6s
Memory limit
128 MB
Judgeable
History class
Hard8
Intervals, Topological sort+2
No attempts yet
Time limit
10s
Memory limit
128 MB
Judgeable
Captain Obvious and the Rabbit-Man
Hard8
Math, Number theory+1
No attempts yet
Time limit
6s
Memory limit
128 MB
Judgeable
Connecting Two Islands
Hard8
Graph, Brute force+2
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
ASCII Puzzle
Hard8
Backtracking, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dictionary
Hard8
Trie, String matching+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mixing Colours
Hard8
Dynamic programming, Probability
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Moves on an Infinite Binary Tree
Hard8
Dynamic programming, Tree+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Cleaning the Hallway
Hard8
Geometry, Math+1
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Longest Chain
Hard8
Divide and conquer, Dynamic programming+2
No attempts yet
Time limit
10s
Memory limit
128 MB
Judgeable
Hidden Tree
Hard8
Dynamic programming, Tree+1
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
C(O|W|A*RD*|S)* CROSSWORD Puzzle
Hard8
Backtracking, String matching
No attempts yet
Time limit
10s
Memory limit
128 MB
Judgeable
Palindrome Trip
Hard8
Probability, Graph+2
No attempts yet
Time limit
10s
Memory limit
128 MB
Judgeable
Safari Park
Hard8
Geometry, Tree
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
TV Transmitters
Hard8
Geometry, Intervals+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Increasing Shortest Path
Hard8
Dynamic programming, Shortest path+2
No attempts yet
Time limit
15s
Memory limit
256 MB
Judgeable
Absurdistan Roads
Hard8
Minimum spanning tree, Graph+1
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Exponential Towers
Hard8
Number theory, Combinatorics+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Highway of the Future
Hard8
Geometry, Sorting+2
No attempts yet
Time limit
10s
Memory limit
128 MB
Judgeable
2D Solar System
Hard8
Geometry, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mixed Flight Plans
Hard8
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Wedding Hall
Hard8
Geometry, Binary search+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Motorway
Hard8
Math, Geometry+1
No attempts yet
Time limit
6s
Memory limit
128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
BricksCount prime multisets of N obtainable by splitting N in two and then splitting both sides the same number of times.	Hard8	Dynamic programmingNumber theory+1	No attempts yet	3s	128 MB	Judgeable
Wi-Fi NetworkDecide whether a point in an open square sees all two or three computers through straight segments that cross none of up to 100 walls.	Hard8	GeometryBrute force	No attempts yet	1s	128 MB	Judgeable
PromotionFind the smallest assignment of employees to allowed positions that fills every required position and promotes every required employee.	Hard8	Graph	No attempts yet	1s	128 MB	Judgeable
Hossa (Bull Market)Given a hossa permutation, output the next hossa in the defined recursive order.	Hard8	CombinatoricsRecursion	No attempts yet	1s	128 MB	Judgeable
Autumn TripDecide whether an undirected graph contains a simple cycle that visits an even number of vertices.	Hard8	GraphDFS	No attempts yet	1s	128 MB	Judgeable
Text AlgorithmsMove a pawn from the bottom-right to the top-left of a grid where left and up steps cost 1 and diagonal steps are free when row and column colors match.	Hard8	Dynamic programmingString matching	No attempts yet	1s	128 MB	Judgeable
Hey, Better BettorGiven a refund rate on final losses and a win chance below half per dollar bet, compute the maximum expected profit over any stopping strategy.	Hard8	ProbabilityDynamic programming+1	No attempts yet	4s	128 MB	Judgeable
Surely You CongestRoute the most commuters to intersection 1 along shortest paths so no two enter the same road in the same direction at the same time.	Hard8	GraphShortest path	No attempts yet	10s	256 MB	Judgeable
Prime Factor ArrangementsGiven n, find the smallest integer k greater than 1 whose prime factors admit exactly n distinct orderings.	Hard8	CombinatoricsNumber theory+1	No attempts yet	3s	256 MB	Judgeable
HarvardAssign each variable of a program with nested repeats to a memory bank within capacity to minimize access and select costs.	Hard8	BacktrackingDynamic programming+1	No attempts yet	10s	128 MB	Judgeable
Paper MapYou shift a fixed-size sheet grid over a simple polygon to minimize the sheets sharing positive area with its interior.	Hard8	GeometryBrute force	No attempts yet	20s	128 MB	Judgeable
Matryoshka DollsReassemble a row of dolls into complete 1 to m sets using adjacent merges while minimizing the number of doll openings.	Hard8	Dynamic programmingIntervals	No attempts yet	5s	128 MB	Judgeable
Pirate ChestFind the largest chest with top sides bounded by a and b that rests on a pond footprint and stays just below the raised water level.	Hard8	MathMatrix+1	No attempts yet	15s	128 MB	Judgeable
Contour MapGiven up to 20000 non-crossing convex orthogonal polygons, compute the maximum nesting depth where the outermost level is 1.	Hard8	GeometrySorting+2	No attempts yet	3s	128 MB	Judgeable
Critical 3-PathFind three vertex-disjoint paths from each start to its target in a weighted DAG with maximum total weight.	Hard8	Dynamic programmingGraph+1	No attempts yet	3s	128 MB	Judgeable
PandoraGiven the left/right turn sequence of a rectilinear polygon, count the coordinate axes it is monotone with respect to.	Hard8	GeometryString	No attempts yet	1s	128 MB	Judgeable
Sports Channel GSKGiven match start times, durations, and travel times, find the largest set of matches in which no reporter can cover any two.	Hard8	GraphSorting	No attempts yet	2s	128 MB	Judgeable
Block CompactionRepeatedly drop axis-aligned rectangles down and then left until none moves, and report the width and height of the final bounding box.	Hard8	SimulationGeometry+2	No attempts yet	1s	128 MB	Judgeable
String PhoneDecide whether each building can post its officer on one of its four corners so that every string length equals the street distance between the pair it joins.	Hard8	GraphDFS	No attempts yet	1s	128 MB	Judgeable
InstallationsOrder jobs with given service times and deadlines to minimize the sum of the two largest lateness penalties.	Hard8	Dynamic programmingSorting+1	No attempts yet	1s	128 MB	Judgeable
Opening a RestaurantCount the grid intersections that beat every existing restaurant in distance to apartment A or to apartment B.	Hard8	GeometrySorting+1	No attempts yet	5s	128 MB	Judgeable
KTX Train DepotFind the smallest number of straight tracks on which trains entering from either end before midnight can all leave toward their fixed ends on time.	Hard8	GreedySorting+1	No attempts yet	5s	128 MB	Judgeable
KingdomRoads merge cities into connected states over time, and each query asks how many states a horizontal line meets and how many cities those states contain.	Hard8	Union-findSegment tree+2	No attempts yet	1s	128 MB	Judgeable
JinhanPut each city on a line with city 1 at zero so all given distances hold and points differ, then give the lexicographically smallest sequence or impossible.	Hard8	Union-findGreedy	No attempts yet	2s	128 MB	Judgeable
HomingGiven a weighted graph and a fixed shortest route, find the smallest fuel load that still brings the driver home when one road on the route is blocked.	Hard8	Shortest pathGraph	No attempts yet	1s	128 MB	Judgeable
MetalCount how many simple monotone polygons use the given n points as vertices.	Hard8	Dynamic programmingGeometry+1	No attempts yet	1s	128 MB	Judgeable
Grid PanelGiven a panel with holes, find the smallest rectilinear convex region that covers every cell next to a hole plus one full row or column.	Hard8	GeometryBrute force	No attempts yet	1s	128 MB	Judgeable
RoommateTwo roommates follow fixed appliance orders with person-specific durations while sharing each appliance, and the task is to find the earliest time both finish.	Hard8	Dynamic programmingShortest path	No attempts yet	1s	128 MB	Judgeable
Fire TowerPlace a vertical tower on a polygonal mountain chain and find the smallest height whose top sees every point above the terrain.	Hard8	GeometryBinary search	No attempts yet	1s	128 MB	Judgeable
Depth OrderGiven a pixel image of overlapping axis-aligned rectangles, decide whether it is realizable and report the possible depth range of one queried rectangle.	Hard8	Topological sortGraph+2	No attempts yet	1s	128 MB	Judgeable
Cycle GameGiven a cycle with numbered edges and a coin on one vertex, decide if the player to move wins when each move lowers an incident edge and crosses it.	Hard8	Game theory	No attempts yet	1s	128 MB	Judgeable
Intelligent RobotsDecide whether a square robot moving only horizontally and vertically can leave the bounding rectangle of a rectilinear polygon without touching it.	Hard8	GeometryGraph+1	No attempts yet	1s	128 MB	Judgeable
Digital OnionGiven a balanced parentheses string, output the string that comes next in the defined price order.	Hard8	CombinatoricsRecursion+1	No attempts yet	1s	128 MB	Judgeable
The K-LeagueFor each team, decide whether remaining games can end with no team holding more wins than it.	Hard8	Graph	No attempts yet	1s	128 MB	Judgeable
A Lazy WorkerJobs have processing times with arrival times and deadlines, and the worker picks among available jobs without idling to minimize total executed work.	Hard8	Dynamic programmingSorting	No attempts yet	1s	128 MB	Judgeable
PCBPlace two clocks and assign each of N points to one clock of capacity K to minimize the largest Manhattan distance from a point to its clock.	Hard8	GeometryBinary search	No attempts yet	1s	128 MB	Judgeable
CastlesFind the minimum Manhattan distance between any west-bank castle and any east-bank castle from two monotone chains.	Hard8	GeometrySorting+1	No attempts yet	1s	128 MB	Judgeable
StainsTaeyeon covers integer points off the x-axis with diamonds centered on the x-axis and minimizes the sum of their areas.	Hard8	Dynamic programmingGeometry+2	No attempts yet	1s	128 MB	Judgeable
Sewerage PlanningFind the line through the rectangle that maximizes the minimum distance to the given points.	Hard8	GeometryBinary search	No attempts yet	1s	128 MB	Judgeable
Detective ConanDecide whether directed sighting reports can match overlapping library visits where each overlap shows at least one sighting.	Hard8	Graph	No attempts yet	1s	128 MB	Judgeable
Tree LabelingThe program counts labelings of a tree with up to 1000 vertices that preserve each label's neighbor label set.	Hard8	TreeCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
Straightening a bent wireDecide whether an axis-aligned wire can be straightened joint by joint from one end without ever touching itself during each unfolding.	Hard8	GeometrySimulation	No attempts yet	1s	128 MB	Judgeable
BooksortGiven a permutation of 1 to n with n at most 15, find the fewest adjacent block swaps that sort it, reporting 5 or more when the minimum exceeds 4.	Hard8	BacktrackingBrute force+1	No attempts yet	1s	128 MB	Judgeable
Triangle WarFrom a partially filled triangular grid of 10 dots and 18 lines, decide which player wins Triangle War under perfect play.	Hard8	Game theoryBrute force+2	No attempts yet	1s	128 MB	Judgeable
Rotate and RewriteDecide whether two rotatable integer sequences can be reduced to a common sequence by substring rewrite rules and report the greatest such length.	Hard8	Dynamic programmingString matching+1	No attempts yet	15s	128 MB	Judgeable
RingworldGiven n circular arcs on a ring of m cities, decide whether each arc can take a distinct city inside it.	Hard8	GreedyIntervals+1	No attempts yet	2s	128 MB	Judgeable
The King of the NorthFind the cheapest set of grid cells, excluding the castle cell, that blocks every 4-directional path from the castle to the map border.	Hard8	GraphMatrix	No attempts yet	1s	128 MB	Judgeable
Fragment ReassemblyArrange the given text fragments so neighbors share an exact overlap and print the joined text in lines of at most 72 characters.	Hard8	BacktrackingString matching+1	No attempts yet	1s	128 MB	Judgeable
Fine Dining RestaurantFor each banned serial number, count the digit comparisons the described naive left-to-right substring search performs against the concatenated string A.	Hard8	String matchingTrie+1	No attempts yet	3s	128 MB	Judgeable
DanceYou count the arrow layouts that send each dancer from mark i to mark a_i after exactly K moves, modulo 1,000,000,007.	Hard8	Number theoryCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
Checkmate with Two RooksGiven a king and two rooks on a chessboard, find the fewest rook moves to force checkmate under optimal play, or 0 when mate is impossible.	Hard8	Game theoryBFS+1	No attempts yet	5s	128 MB	Judgeable
Red John GameDecide whether an n by n block of pegs on an infinite board can be reduced to one peg by orthogonal jumps that remove the jumped peg.	Hard8	MathCombinatorics	No attempts yet	2s	128 MB	Judgeable
Series-Parallel Parking LotPlace as many extra cars as possible on empty spaces of the encoded lot so every car still reaches the exit through empty spaces.	Hard8	Dynamic programmingTree+1	No attempts yet	2s	256 MB	Judgeable
ZZStarting from Fibonacci-like values a and b, repeat prefix sums c times and output the d-th value modulo 1000000009.	Hard8	CombinatoricsNumber theory+1	No attempts yet	15s	64 MB	Judgeable
Bribing the SyndicateChoose an adaptive bribery order within a fixed budget to maximize the chance of gaining at least c defectors.	Hard8	Dynamic programmingProbability	No attempts yet	5s	128 MB	Judgeable
Indisputable RightGiven antennas on a ridge of triangular mountains, find the fewest extra antennas on the ridge that connect all of them by line of sight.	Hard8	GeometryGraph+2	No attempts yet	1s	128 MB	Judgeable
The Avaricious ISPChoose two disjoint disks over weighted points to maximize the product of the covered weight sums.	Hard8	GeometrySorting+1	No attempts yet	1s	128 MB	Judgeable
Tracking RobotsCount the fewest and most robots whose walks from region 1 interleave to produce the recorded region-label stream.	Hard8	Graph	No attempts yet	1s	128 MB	Judgeable
Correcting CuriosityGiven two strings, find the length of the shortest substitution command that rewrites the first into the second.	Hard8	String matchingString+1	No attempts yet	2s	256 MB	Judgeable
GaragePlace the fewest axis-aligned w by h garages inside a W by H lot so no additional garage fits without moving them.	Hard8	GeometryMath+1	No attempts yet	2s	256 MB	Judgeable
Intellectual PropertyDecide for each pair of 9x9 Sudoku grids whether digit relabeling, row and column band swaps, and transposition turn one into the other.	Hard8	BacktrackingBrute force+1	No attempts yet	2s	256 MB	Judgeable
JEvaluate a J-style vector expression over up to 100000 entries using low-degree polynomials per component and output the scalar result modulo 10^9.	Hard8	MathImplementation	No attempts yet	2s	256 MB	Judgeable
Golf FieldChoose four of up to 30000 points in the plane so their convex hull has the largest possible area.	Hard8	GeometryTwo pointers	No attempts yet	2s	128 MB	Judgeable
PasswordsFind the longest prefix length and suffix length from two distinct set strings whose repetitions coincide.	Hard8	String matchingString	No attempts yet	7s	128 MB	Judgeable
String PathCount the N by M letter grids where two given strings each appear on a down-right path from the top-left to the bottom-right corner.	Hard8	Dynamic programmingCombinatorics	No attempts yet	1s	128 MB	Judgeable
Pascal Matrix PowerCompute the entry at row R and column C of the P-th power of the Pascal matrix for each test case.	Hard8	CombinatoricsMath	No attempts yet	1s	128 MB	Judgeable
Beautiful LandscapeMove blocks between neighboring stacks at unit cost so occupied positions sit at pairwise prime distances using the fewest moves.	Hard8	Dynamic programmingPrefix sum+1	No attempts yet	20s	128 MB	Judgeable
Electric Car RallyPlan driving and charging stops across time-dependent roads to reach the last station as early as possible.	Hard8	Shortest pathGraph+1	No attempts yet	1s	128 MB	Judgeable
Tandem RepeatsCount substrings of even length whose first half equals the second half in each DNA string.	Hard8	String matchingDivide and conquer	No attempts yet	1s	128 MB	Judgeable
Leave Your NameEnter the given uppercase name with the fewest presses of letter-change, cursor-move, and insert buttons.	Hard8	Dynamic programmingBit manipulation+1	No attempts yet	12s	128 MB	Judgeable
Beautiful RectangleComplete each erased cell with / or \ so the grid graph with all diagonals is properly 3-colorable and the pattern is lexicographically smallest.	Hard8	GraphUnion-find+1	No attempts yet	1s	128 MB	Judgeable
Crusher's CodeCompute the expected number of loop iterations for two randomized swap sorts on arrays of up to 8 values.	Hard8	ProbabilityDynamic programming+1	No attempts yet	10s	128 MB	Judgeable
Janeway's JourneyFind the single straight line that hits the greatest number of disjoint circular asteroids in the plane.	Hard8	GeometrySorting+1	No attempts yet	40s	128 MB	Judgeable
Mass ProductionDesign one identical kit of base parts for every ship so the cheapest conversion into the required Class A and Class B components costs the least in total.	Hard8	GraphMath	No attempts yet	2s	128 MB	Judgeable
KkunglishFor each query range, the program reports the case-insensitive occurrence of T with the most case differences, or -1 if none, then flips the case of the range.	Hard8	Segment treeString matching	No attempts yet	2s	128 MB	Judgeable
Disjoint water supplyCount the pairs of cities with paths from city 1 that meet only at city 1 in a pipe network ordered by decreasing altitude.	Hard8	GraphTopological sort+2	No attempts yet	1s	128 MB	Judgeable
Inverting HuffmanGiven code lengths that some Huffman run can produce, find the smallest total character count that allows those lengths.	Hard8	GreedyTree+1	No attempts yet	1s	128 MB	Judgeable
Rubik's RectangleDecide whether repeatedly reversing whole rows or columns can sort a given H by W tile board.	Hard8	MathCombinatorics	No attempts yet	6s	128 MB	Judgeable
History classFind the event order that respects disjoint time order and minimizes the largest position gap between overlapping intervals.	Hard8	IntervalsTopological sort+2	No attempts yet	10s	128 MB	Judgeable
Captain Obvious and the Rabbit-ManGiven the first k power sums of a hidden exponential combination modulo a prime, compute the next term through its implied linear recurrence.	Hard8	MathNumber theory+1	No attempts yet	6s	128 MB	Judgeable
Connecting Two IslandsFill destroyed tracks and ferry routes with 0 or 1 so every triple meets the triangle inequality, and print the lexicographically smallest valid plan.	Hard8	GraphBrute force+2	No attempts yet	3s	128 MB	Judgeable
ASCII PuzzleYou reassemble k shuffled pieces with jagged borders into the original rectangle and print the lexicographically smallest layout.	Hard8	BacktrackingBrute force+1	No attempts yet	1s	128 MB	Judgeable
DictionaryGiven up to 50 short words, find the fewest vertices of an edge-labeled tree whose downward paths contain every word.	Hard8	TrieString matching+2	No attempts yet	1s	128 MB	Judgeable
Mixing ColoursThe player picks one colour per token and merges adjacent tokens under the rules to maximize the product of picked certainties, breaking ties in ASCII order.	Hard8	Dynamic programmingProbability	No attempts yet	5s	128 MB	Judgeable
Moves on an Infinite Binary TreeStarting from the node reached by S, count the distinct nodes reachable by following any subsequence of T on an infinite binary tree.	Hard8	Dynamic programmingTree+1	No attempts yet	2s	128 MB	Judgeable
Cleaning the HallwayGiven up to 500 outlets, each cleaning the ring swept by a small disk around a circle, compute the area of their union rounded to two decimals.	Hard8	GeometryMath+1	No attempts yet	5s	128 MB	Judgeable
Longest ChainFind the longest chain of triples with all three coordinates strictly increasing among up to 300,000 points per dataset.	Hard8	Divide and conquerDynamic programming+2	No attempts yet	10s	128 MB	Judgeable
Hidden TreeFind the longest subsequence that forms the leaves of a binary tree where each internal node has equal left and right sums.	Hard8	Dynamic programmingTree+1	No attempts yet	5s	128 MB	Judgeable
C(O\|W\|ARD\|S)* CROSSWORD PuzzleFill a 2 to 4 by 2 to 4 grid with capital letters so each row and column matches its regex clue, and report the unique solution, none, or ambiguous.	Hard8	BacktrackingString matching	No attempts yet	10s	128 MB	Judgeable
Palindrome TripCompute the chance that a uniform random walk from s to t spells a palindrome, stopping early when t becomes unreachable.	Hard8	ProbabilityGraph+2	No attempts yet	10s	128 MB	Judgeable
Safari ParkTriangles are inserted one at a time and each query asks which earlier triangle strictly contains a point, reporting -1 on a boundary and 0 outside.	Hard8	GeometryTree	No attempts yet	5s	128 MB	Judgeable
TV TransmittersSome rooftops hold transmitters, buildings block their straight rays, and the total length of ground that sees one transmitter is printed as a reduced fraction.	Hard8	GeometryIntervals+1	No attempts yet	1s	128 MB	Judgeable
Increasing Shortest PathFind the cheapest A to B path using at most C edges whose weights strictly increase.	Hard8	Dynamic programmingShortest path+2	No attempts yet	15s	256 MB	Judgeable
Absurdistan RoadsGiven all-pairs shortest distances, find the minimum total length of a connected N-edge road network that reproduces the table.	Hard8	Minimum spanning treeGraph+1	No attempts yet	5s	128 MB	Judgeable
Exponential TowersGiven a power tower a^(b^c), count the towers of height at least 3 with bases above 1 that evaluate to the same value.	Hard8	Number theoryCombinatorics+1	No attempts yet	2s	128 MB	Judgeable
Highway of the FutureGiven each car entry time and speed, compute the largest number of cars at the same spot at the same time on a 100-unit highway.	Hard8	GeometrySorting+2	No attempts yet	10s	128 MB	Judgeable
2D Solar SystemCircles tangent to one straight line glide with constant velocity, and the program reports when the first two touch.	Hard8	GeometrySorting+2	No attempts yet	1s	128 MB	Judgeable
Mixed Flight PlansCompute the cheapest cost to send two bags with direct and fixed-price indirect flights, either separately or by swapping bags at a shared airport.	Hard8	Shortest pathGraph+1	No attempts yet	1s	128 MB	Judgeable
Wedding HallFind the largest L-shaped hall of three equal squares that fits inside a walled garden without enclosing any tree.	Hard8	GeometryBinary search+2	No attempts yet	1s	128 MB	Judgeable
The MotorwayGiven sorted entry positions, find the smallest and largest even toll spacing that puts one entry between consecutive tolls, printed as reduced fractions.	Hard8	MathGeometry+1	No attempts yet	6s	128 MB	Judgeable