Problems

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Total results29,054 problems

Restoring the Erased Equation (Large)
Medium7
Dynamic programming, Greedy+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Bacteria Growth (Small)
Medium7
Number theory, Recursion
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Bacteria Growth (Large)
Medium7
Number theory, Recursion+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Number Sets (Large)
Medium7
Union-find, Number theory
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Permutations with Equal Runs
Medium7
Dynamic programming, Combinatorics
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Program within a Program (Large)
Medium7
Bit manipulation, Implementation
No attempts yet
Time limit
60s
Memory limit
512 MB
Judgeable
Perpetual Motion (Large)
Medium7
Graph, Union-find+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Expensive Dinner (Small)
Medium7
Number theory, Math+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Space Emergency (Large)
Medium7
Greedy, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Revenge of the Hot Dogs (Large)
Medium7
Binary search, Greedy+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
House of Kittens (Large)
Medium7
Graph, Geometry+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
The Killer Word (Large)
Medium7
Trie, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Pseudominion (Large)
Medium7
Greedy, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Champion Sort (Large)
Medium7
Probability, Combinatorics+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Extreme Escalator Pogo (Small)
Medium7
Graph, BFS+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Vanishing Numbers
Medium7
Math, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Battlefield
Medium7
Graph, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Letter Stamper (Small)
Medium7
Dynamic programming, Stack
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Letter Stamper (Large)
Medium7
Dynamic programming, Stack
No attempts yet
Time limit
15s
Memory limit
512 MB
Judgeable
City Tour (Small)
Medium7
Dynamic programming, Graph
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Candy Store (Small)
Medium7
Dynamic programming, Greedy
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Candy Store (Large)
Medium7
Greedy, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Travel Plan
Medium7
Dynamic programming, Brute force
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
De-RNG-ed (Large)
Medium7
Number theory, Brute force+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Fence
Medium7
Dynamic programming, Number theory+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Hot Dog Proliferation (Small)
Medium7
Dynamic programming, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Hot Dog Proliferation
Medium7
Math, Greedy+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
World Cup 2010 (Large)
Medium7
Dynamic programming, Tree
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Bacteria (Large)
Medium7
Dynamic programming, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Load Testing (Small)
Medium7
Dynamic programming, Binary search
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Load Testing (Large)
Medium7
Binary search, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Making Chess Boards (Large)
Medium7
Dynamic programming, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Your Rank is Pure (Small)
Medium7
Dynamic programming, Combinatorics
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Your Rank is Pure (Large)
Medium7
Dynamic programming, Combinatorics
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Make it Smooth (Large)
Medium7
Dynamic programming, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Number Game (Small)
Medium7
Game theory, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Number Game
Medium7
Game theory, Number theory+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Year of More Code Jam (Small)
Medium7
Math, Probability+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
A Year of More Contests
Medium7
Probability, Math+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Doubly Sorted Grid
Medium7
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
40s
Memory limit
512 MB
Judgeable
Wi-Fi Tower Upgrade
Medium7
Graph, Greedy+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Marbles
Medium7
Stack, Greedy
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Alphabetomials (Large)
Medium7
Dynamic programming, Combinatorics+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Interesting Ranges (Small)
Medium7
Math, Combinatorics+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
A Digging Problem
Medium7
BFS, Graph+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
A Digging Problem (Large)
Medium7
Graph, Shortest path+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Stock Charts (Large)
Medium7
Graph, Union-find+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Seconds Before the War
Medium7
Greedy, Math+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Bribe the Prisoners (Small)
Medium7
Dynamic programming, Divide and conquer+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Bribe the Prisoners (Large)
Medium7
Dynamic programming, Divide and conquer+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
The Next Number
Medium7
Greedy, Backtracking+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Square Math (Large)
Medium7
BFS, Graph+2
No attempts yet
Time limit
15s
Memory limit
512 MB
Judgeable
Crossing the Road (Large)
Medium7
Shortest path, Graph+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Collecting Cards
Medium7
Dynamic programming, Probability+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Collecting Every Card
Medium7
Probability, Dynamic programming+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Juice Blend
Medium7
Geometry, Implementation+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Mine Layer (Large)
Medium7
Dynamic programming, Implementation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Rainbow Trees
Medium7
Tree, Greedy+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Mixing Bowls (Large)
Medium7
Tree, DFS+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Code Sequence
Medium7
Math, Number theory+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Test Passing Probability (Small)
Medium7
Dynamic programming, Probability+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
What Are Birds? (Large)
Medium7
Array, Intervals+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Apocalypse Soon (Small)
Medium7
Simulation, Greedy+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
How Big Are the Pockets? (Small)
Medium7
Geometry, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Endless Knight (Large)
Medium7
Dynamic programming, Combinatorics+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Star Wars (Large)
Medium7
Binary search, Geometry+1
No attempts yet
Time limit
30s
Memory limit
512 MB
Judgeable
Mousetrap (Large Input)
Medium7
Simulation, Implementation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Spinner (Large)
Medium7
Simulation, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Mixture (Large)
Medium7
Math, Greedy+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Busiest railway segment (large)
Medium7
Tree, DFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Coloring Practice (Small)
Medium7
Combinatorics, Brute force+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Park
Medium7
Geometry, Union-find+2
No attempts yet
Time limit
2.5s
Memory limit
256 MB
Judgeable
Cities
Medium7
Minimum spanning tree, Dynamic programming+2
No attempts yet
Time limit
4s
Memory limit
256 MB
Judgeable
Heavenly Dragon Flash
Medium7
Dynamic programming, Number theory
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Eternal Youth
Medium7
Math, Binary search+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Oil
Medium7
Geometry, Sorting+2
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Swap Space
Medium7
Greedy, Sorting+2
No attempts yet
Time limit
6s
Memory limit
512 MB
Judgeable
What Really Happened on Mars?
Medium7
Simulation, Greedy+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Block Game
Medium7
Implementation, Geometry+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
My matrix multiplication travelogue
Medium7
Dynamic programming, Matrix+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Alchemy
Medium7
Combinatorics, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Diamond Inheritance
Medium7
Graph, DFS+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Torrent
Medium7
Tree, BFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Gregory and the Bank
Medium7
Greedy, Sorting+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Choosing a T-shirt
Medium7
Game theory, Backtracking+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Train in a Tunnel
Medium7
Array, Two pointers+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Beautiful Partition
Medium7
Number theory, Math+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Problem Preparation
Medium7
Math, Prefix sum+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Cubic Art
Medium7
Segment tree, Simulation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Critical Subprojects
Medium7
Graph, Topological sort+1
No attempts yet
Time limit
0.6s
Memory limit
32 MB
Judgeable
Game
Medium7
Game theory, Math
No attempts yet
Time limit
0.1s
Memory limit
1024 MB
Judgeable
Mission
Medium7
Graph, Shortest path
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
An inexperienced slalomer
Medium7
Geometry, Binary search+1
No attempts yet
Time limit
0.3s
Memory limit
1024 MB
Judgeable
Range XOR
Medium7
Bit manipulation, Segment tree+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Hide and Seek 2
Medium7
BFS, Graph+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Aurora Borealis
Medium7
Geometry, Binary search+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bribing the Prisoners
Medium7
Dynamic programming, Intervals+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Finding a string with enough inversions
Medium7
Backtracking, Combinatorics+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Mutalisk 2
Medium7
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Distinct valid bracket subsequences
Medium7
Dynamic programming, String+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Restoring the Erased Equation (Large)Fill every ? with a digit so the addition or subtraction holds without leading zeros and the whole equation is lexicographically smallest.	Medium7	Dynamic programmingGreedy+1	No attempts yet	5s	512 MB	Judgeable
Bacteria Growth (Small)Apply the map x to x^x exactly B times starting from A and report the result modulo C.	Medium7	Number theoryRecursion	No attempts yet	5s	512 MB	Judgeable
Bacteria Growth (Large)Starting from A bacteria that grow from x to x^x each hour, compute the count after B hours modulo C.	Medium7	Number theoryRecursion+1	No attempts yet	5s	512 MB	Judgeable
Number Sets (Large)Count the remaining groups after merging interval numbers that share a prime factor of at least P.	Medium7	Union-findNumber theory	No attempts yet	5s	512 MB	Judgeable
Permutations with Equal RunsCount distinct rearrangements of each string that keep the original number of maximal blocks of equal letters, modulo 1000003.	Medium7	Dynamic programmingCombinatorics	No attempts yet	5s	512 MB	Judgeable
Program within a Program (Large)Write a robot program of at most 30 statements that moves the robot exactly N lampposts east and makes it release the cake there.	Medium7	Bit manipulationImplementation	No attempts yet	60s	512 MB	Judgeable
Perpetual Motion (Large)Count ways to direct each belt on a toroidal grid so no two lemmings ever share a square, modulo 1000003.	Medium7	GraphUnion-find+1	No attempts yet	5s	512 MB	Judgeable
Expensive Dinner (Small)Each friend is happy only when the running total is a multiple of their number, so find how the arrival order changes the number of waiter calls for N friends.	Medium7	Number theoryMath+1	No attempts yet	5s	512 MB	Judgeable
Space Emergency (Large)Choose up to L stars for speed boosters on a route with repeating leg lengths so the flagship reaches the last star as early as possible.	Medium7	GreedySorting+1	No attempts yet	5s	512 MB	Judgeable
Revenge of the Hot Dogs (Large)Vendors starting at given points all move at speed 1, and you must find the least time in which they can stand pairwise at least D apart.	Medium7	Binary searchGreedy+1	No attempts yet	5s	512 MB	Judgeable
House of Kittens (Large)Assign a flavor to each polygon vertex so that every room touches each flavor used, maximizing the flavor count.	Medium7	GraphGeometry+1	No attempts yet	5s	512 MB	Judgeable
The Killer Word (Large)Choose the dictionary word that forces the most wrong letter guesses from a guesser who tries letters in a fixed order while ruling out inconsistent words.	Medium7	TrieSimulation+1	No attempts yet	5s	512 MB	Judgeable
Pseudominion (Large)Play cards with draw, score and turn bonuses in the best order to maximize the final score before the turns run out.	Medium7	GreedySorting	No attempts yet	5s	512 MB	Judgeable
Champion Sort (Large)Find the minimum expected number of uniform shuffles of adaptively chosen positions needed to sort a permutation of 1 to N.	Medium7	ProbabilityCombinatorics+1	No attempts yet	5s	512 MB	Judgeable
Extreme Escalator Pogo (Small)Starting from the best blue step on a circular escalator, pick jump heights that change by at most one to maximize the height reached before landing on red.	Medium7	GraphBFS+1	No attempts yet	5s	512 MB	Judgeable
Vanishing NumbersSort the given decimals by the round in which repeated middle-third deletion removes them, listing numbers that survive every round last in increasing order.	Medium7	MathSimulation+1	No attempts yet	5s	512 MB	Judgeable
BattlefieldCompute the fewest new roads needed so one closed tour can traverse every road exactly once.	Medium7	GraphMath	No attempts yet	5s	512 MB	Judgeable
Letter Stamper (Small)Print a given string of A, B and C with push, pop and print on a letter stack using the fewest operations.	Medium7	Dynamic programmingStack	No attempts yet	5s	512 MB	Judgeable
Letter Stamper (Large)Find the fewest stack pushes, pops, and prints needed to print each target string of A, B, and C grades in order.	Medium7	Dynamic programmingStack	No attempts yet	15s	512 MB	Judgeable
City Tour (Small)Find the most vertices a single closed tour can visit when each street and point is used at most once in a city grown one triangle at a time.	Medium7	Dynamic programmingGraph	No attempts yet	5s	512 MB	Judgeable
Candy Store (Small)Pick the fewest integer-weight boxes so up to k visitors, each asking 1 to C grams in unknown order, each receive an exact subset of the remaining boxes.	Medium7	Dynamic programmingGreedy	No attempts yet	5s	512 MB	Judgeable
Candy Store (Large)Choose the fewest box sizes so any sequence of up to k orders of 1 to C grams can be paid exactly with whole boxes.	Medium7	GreedyMath	No attempts yet	5s	512 MB	Judgeable
Travel PlanStarting from Earth, visit each of the N planets on a line exactly once, return to Earth, and burn the largest total distance within fuel F.	Medium7	Dynamic programmingBrute force	No attempts yet	5s	512 MB	Judgeable
De-RNG-ed (Large)Given K consecutive outputs of a linear congruential generator with unknown prime modulus up to 10^D, decide the uniquely forced next term or report ambiguity.	Medium7	Number theoryBrute force+1	No attempts yet	5s	512 MB	Judgeable
FencePick the fewest boards from the given lengths of at most 100 so they sum to exactly L up to 1e18, or report IMPOSSIBLE.	Medium7	Dynamic programmingNumber theory+1	No attempts yet	5s	512 MB	Judgeable
Hot Dog Proliferation (Small)Vendors sharing a corner split one step east and one step west per move, and the task asks for the fewest moves that leave every vendor on a distinct corner.	Medium7	Dynamic programmingSorting	No attempts yet	5s	512 MB	Judgeable
Hot Dog ProliferationSpread vendors sharing corners with pair splits that send one vendor east and one west, using the fewest moves so every corner holds at most one vendor.	Medium7	MathGreedy+2	No attempts yet	5s	512 MB	Judgeable
World Cup 2010 (Large)Pick the cheapest tickets in a knockout bracket so each team misses at most M[i] of the matches it plays, no matter who wins.	Medium7	Dynamic programmingTree	No attempts yet	5s	512 MB	Judgeable
Bacteria (Large)Given initially filled rectangles on a grid evolving by a north-west neighbor rule, compute the seconds until no bacterium remains.	Medium7	Dynamic programmingSimulation+1	No attempts yet	5s	512 MB	Judgeable
Load Testing (Small)For each case, compute the fewest adaptive load tests that guarantee bracketing the capacity within a factor of C in the worst case.	Medium7	Dynamic programmingBinary search	No attempts yet	5s	512 MB	Judgeable
Load Testing (Large)For each case with known good load L and known bad load P, compute the worst-case number of adaptive tests that pins capacity within factor C.	Medium7	Binary searchMath	No attempts yet	5s	512 MB	Judgeable
Making Chess Boards (Large)Repeatedly cut the largest alternating-color square, breaking ties by topmost then leftmost position, and report how many boards of each size result.	Medium7	Dynamic programmingSimulation+1	No attempts yet	5s	512 MB	Judgeable
Your Rank is Pure (Small)Count subsets of 2 to n containing n whose repeated rank mapping stays inside the set until it reaches 1, modulo 100003.	Medium7	Dynamic programmingCombinatorics	No attempts yet	5s	512 MB	Judgeable
Your Rank is Pure (Large)Count the subsets of 2 to n that contain n and whose repeated rank mapping from n reaches 1.	Medium7	Dynamic programmingCombinatorics	No attempts yet	5s	512 MB	Judgeable
Make it Smooth (Large)Edit pixel values, delete pixels, or insert new ones at given costs so neighboring values differ by at most M for the lowest total price.	Medium7	Dynamic programmingMath	No attempts yet	5s	512 MB	Judgeable
Number Game (Small)Count the pairs (A, B) in the given rectangle from which the first player wins the subtract-a-multiple game where hitting zero loses.	Medium7	Game theoryMath	No attempts yet	5s	512 MB	Judgeable
Number GameCount the pairs in the given rectangle from which the first player wins the subtraction game where moving to zero or below loses.	Medium7	Game theoryNumber theory+2	No attempts yet	5s	512 MB	Judgeable
Year of More Code Jam (Small)Given T tournaments with fixed round offsets and N equally likely start days, compute the exact expected value of the sum of squared daily round counts.	Medium7	MathProbability+1	No attempts yet	5s	512 MB	Judgeable
A Year of More ContestsGiven T tournaments with fixed round offsets, each starting on a uniformly random day among N, compute the exact expected sum of squared daily round counts.	Medium7	ProbabilityMath+1	No attempts yet	5s	512 MB	Judgeable
Doubly Sorted GridCount ways to fill a partially filled grid so rows and columns are non-decreasing, modulo 10007, with R and C at most 10.	Medium7	Dynamic programmingCombinatorics+1	No attempts yet	40s	512 MB	Judgeable
Wi-Fi Tower UpgradeChoose a set of towers to upgrade, where each upgraded tower forces every tower in its range to be upgraded, to maximize the total score.	Medium7	GraphGreedy+1	No attempts yet	5s	512 MB	Judgeable
MarblesPairs of matching colors sit on a line; join each pair with a non-crossing path above y=0 and minimize the total height.	Medium7	StackGreedy	No attempts yet	5s	512 MB	Judgeable
Alphabetomials (Large)Given a polynomial over 26 letter counts and a dictionary, sum its value over all phrases of 1 to K dictionary words, modulo 10009.	Medium7	Dynamic programmingCombinatorics+2	No attempts yet	5s	512 MB	Judgeable
Interesting Ranges (Small)Count subranges of [L, R] containing an even number of decimal palindromes, modulo 1000000007, for R up to 10^13.	Medium7	MathCombinatorics+2	No attempts yet	5s	512 MB	Judgeable
A Digging ProblemFind the fewest rock cells to dig so a digger can move sideways through air holes, fall at most F cells, and reach the bottom row.	Medium7	BFSGraph+2	No attempts yet	5s	512 MB	Judgeable
A Digging Problem (Large)In an R x C cave grid, dig the fewest rock cells so you can walk and fall at most F rows to reach any bottom-row cell.	Medium7	GraphShortest path+2	No attempts yet	5s	512 MB	Judgeable
Stock Charts (Large)Each stock is a k-dimensional point; a chart holds points where one stock strictly dominates another at every time, and we need the minimum number of chains covering all points.	Medium7	GraphUnion-find+2	No attempts yet	5s	512 MB	Judgeable
Seconds Before the WarGiven a string of letters and digits treated as a numeral in an unknown base, find the smallest value it can represent.	Medium7	GreedyMath+2	No attempts yet	5s	512 MB	Judgeable
Bribe the Prisoners (Small)Choose the release order of Q prisoners out of P cells to minimize total bribes, where each release bribes every still-occupied prisoner reachable from it until a boundary or empty cell.	Medium7	Dynamic programmingDivide and conquer+2	No attempts yet	5s	512 MB	Judgeable
Bribe the Prisoners (Large)Given prison cells in a row and a set of cells to release one per day, choose the release order that minimizes total bribes paid to prisoners who hear the news.	Medium7	Dynamic programmingDivide and conquer+2	No attempts yet	5s	512 MB	Judgeable
The Next NumberGiven N, the count of each nonzero digit in N defines the whole list; find the next number that has exactly those digit counts.	Medium7	GreedyBacktracking+2	No attempts yet	5s	512 MB	Judgeable
Square Math (Large)On a W by W grid of digits and plus/minus signs, find the shortest lexicographically smallest walk expression producing each queried value.	Medium7	BFSGraph+2	No attempts yet	15s	512 MB	Judgeable
Crossing the Road (Large)Find the minimum time for a pedestrian to travel across a grid of intersections where crossing depends on periodically timed traffic lights.	Medium7	Shortest pathGraph+1	No attempts yet	5s	512 MB	Judgeable
Collecting CardsEach pack is a uniformly random N-subset of C card kinds; find the expected number of packs until all C kinds are collected.	Medium7	Dynamic programmingProbability+1	No attempts yet	5s	512 MB	Judgeable
Collecting Every CardFind the expected number of booster packs to buy, each pack giving N distinct kinds, until all C kinds are collected.	Medium7	ProbabilityDynamic programming+2	No attempts yet	5s	512 MB	Judgeable
Juice BlendFor each test case, choose integer shares of three juices summing to 10000 so that the most guests get at least their per-juice minimums.	Medium7	GeometryImplementation+2	No attempts yet	5s	512 MB	Judgeable
Mine Layer (Large)Given a Minesweeper-style grid of neighbor counts, find the maximum number of mines the middle row can hold in any layout that matches all counts.	Medium7	Dynamic programmingImplementation+1	No attempts yet	5s	512 MB	Judgeable
Rainbow TreesCount rainbow edge colorings of a tree where any two adjacent edges differ and any three consecutive edges all differ, modulo 1e9+9.	Medium7	TreeGreedy+2	No attempts yet	5s	512 MB	Judgeable
Mixing Bowls (Large)Given a recipe where each mixture's ingredients are other mixtures, find the minimum number of bowls needed to prepare it.	Medium7	TreeDFS+2	No attempts yet	5s	512 MB	Judgeable
Code SequenceGiven N consecutive terms of a sequence built from unknown coefficients over GF(10007), find the next term or print UNKNOWN.	Medium7	MathNumber theory+1	No attempts yet	5s	512 MB	Judgeable
Test Passing Probability (Small)With M submissions and Q questions of 4 choices each, find the maximum probability of answering every question correctly, learning only whether each submission passed.	Medium7	Dynamic programmingProbability+1	No attempts yet	5s	512 MB	Judgeable
What Are Birds? (Large)Given labeled points and the fact that birds are exactly the points in a height interval crossed with a weight interval, classify each query as always bird, never bird, or unknown.	Medium7	ArrayIntervals+2	No attempts yet	5s	512 MB	Judgeable
Apocalypse Soon (Small)On a grid of at most 5 by 5, simulate daily simultaneous attacks where each AI nation hits its strongest surviving neighbor, and choose one attack per day to survive as long as possible.	Medium7	SimulationGreedy+2	No attempts yet	5s	512 MB	Judgeable
How Big Are the Pockets? (Small)Walk a closed non-self-touching orthogonal path from run-length encoded moves and sum the area of pockets: cells outside the polygon with boundary both east and west or north and south.	Medium7	GeometrySimulation+1	No attempts yet	5s	512 MB	Judgeable
Endless Knight (Large)Count right-and-down knight paths from (1,1) to (H,W) on a board up to 1e8 wide, avoiding at most 10 rocks, modulo 10007.	Medium7	Dynamic programmingCombinatorics+2	No attempts yet	5s	512 MB	Judgeable
Star Wars (Large)Place a cruiser anywhere in 3D space so that the maximum Manhattan distance to each ship divided by that ship's receiver power is minimized, and report that value to six decimals.	Medium7	Binary searchGeometry+1	No attempts yet	30s	512 MB	Judgeable
Mousetrap (Large Input)In the perfect Mousetrap deck of K cards, report the card value at each queried position.	Medium7	SimulationImplementation+1	No attempts yet	5s	512 MB	Judgeable
Spinner (Large)Given a circular row of R, G, B cells and a three-cell local update rule, count each color after K synchronous rounds with K up to 1e9.	Medium7	SimulationMath	No attempts yet	1s	256 MB	Judgeable
Mixture (Large)Given limited supplies of N materials and two recipes, choose grams of A and B (real amounts) to maximize value, preferring least A.	Medium7	MathGreedy+1	No attempts yet	1s	256 MB	Judgeable
Busiest railway segment (large)Given a tree and Q paths, count how many paths use each edge and report the edge with the maximum count, breaking ties by lexicographic order of endpoints.	Medium7	TreeDFS+2	No attempts yet	2s	512 MB	Judgeable
Coloring Practice (Small)Count distinct colorings of an n-gon's vertices with up to k colors, identifying colorings under rotations, reflections, and color swaps.	Medium7	CombinatoricsBrute force+1	No attempts yet	2s	256 MB	Judgeable
ParkGiven non-overlapping tree circles in a rectangular park, decide for each visitor circle which corner entrances they can reach without overlapping any tree or the fence.	Medium7	GeometryUnion-find+2	No attempts yet	2.5s	256 MB	Judgeable
CitiesGiven a weighted undirected graph, pick a minimum-cost set of edges so that all k special cities (k at most 10) end up in one connected component.	Medium7	Minimum spanning treeDynamic programming+2	No attempts yet	4s	256 MB	Judgeable
Heavenly Dragon FlashCount sequences of nondecreasing cut heights where each cut divides the object's height, modulo 1000000007.	Medium7	Dynamic programmingNumber theory	No attempts yet	2s	128 MB	Judgeable
Eternal YouthFind the largest base b in which y has only decimal digits 0-9 and whose digit string, read as decimal, is at least l.	Medium7	MathBinary search+1	No attempts yet	1s	512 MB	Judgeable
OilGiven up to 2000 horizontal segments at distinct points, find the maximum total length of segments intersected by a single non-horizontal line from the origin.	Medium7	GeometrySorting+2	No attempts yet	10s	512 MB	Judgeable
Swap SpaceGiven n drives with old and new capacities, find the smallest extra drive size so all drives can be reformatted one at a time while losing no data.	Medium7	GreedySorting+2	No attempts yet	6s	512 MB	Judgeable
What Really Happened on Mars?Simulate a real-time task scheduler under the priority ceiling protocol and print the finish time of each task.	Medium7	SimulationGreedy+2	No attempts yet	2s	512 MB	Judgeable
Block GameA ball launched at 45 degrees bounces off three walls of a grid; count how many distinct polyomino blocks its 45-degree path passes through the interior of.	Medium7	ImplementationGeometry+2	No attempts yet	1s	128 MB	Judgeable
My matrix multiplication travelogueGiven K, output dimension array a0..aN whose worst and best matrix-chain multiplication counts differ by exactly K, with the smallest lexicographic answer.	Medium7	Dynamic programmingMatrix+2	No attempts yet	1s	128 MB	Judgeable
AlchemyA product is a multiset of n ingredients chosen from m qualities; find the sum of the products of qualities over all such multisets, mod 1e9+7.	Medium7	CombinatoricsMath+1	No attempts yet	1s	128 MB	Judgeable
Diamond InheritanceProcess class declarations in order, accepting each only if the name is fresh, all parents exist, and no diamond forms.	Medium7	GraphDFS+1	No attempts yet	2s	512 MB	Judgeable
TorrentTwo computers start with a file in a tree; each minute, adjacent computers can copy in parallel subject to one copy per computer. Find the minimum minutes until all nodes have the file.	Medium7	TreeBFS+2	No attempts yet	2s	512 MB	Judgeable
Gregory and the BankGiven fixed incoming and outgoing amounts plus a schedule of receiving and sending days, assign each transfer to a day to maximize suppliers paid.	Medium7	GreedySorting+1	No attempts yet	2s	256 MB	Judgeable
Choosing a T-shirtThree players alternately cross out numbers from 1 to n, each trying to leave the survivor highest on his own ranking; find the survivor.	Medium7	Game theoryBacktracking+1	No attempts yet	2s	256 MB	Judgeable
Train in a TunnelGiven car lengths and light states, find the minimum number of extra lights to turn on so that at every moment some lit car overlaps the tunnel.	Medium7	ArrayTwo pointers+2	No attempts yet	2s	256 MB	Judgeable
Beautiful PartitionSplit an array into two non-empty parts and maximize the smaller of the two part gcds.	Medium7	Number theoryMath+2	No attempts yet	2s	256 MB	Judgeable
Problem PreparationMaintain an array under point increments and decrements, and after each update answer the sum of ceil(t_i / k) for a given k.	Medium7	MathPrefix sum+2	No attempts yet	2s	256 MB	Judgeable
Cubic ArtGiven a cube state and a move sequence, apply point updates that replace one move and print the resulting cube state after each update.	Medium7	Segment treeSimulation+2	No attempts yet	1s	1024 MB	Judgeable
Critical SubprojectsFind every vertex in a DAG that is comparable to all other vertices under reachability.	Medium7	GraphTopological sort+1	No attempts yet	0.6s	32 MB	Judgeable
GameFor each pair of positive integers A and B, decide who wins a subtraction game where a player may subtract any positive multiple of the smaller number from the larger, or take the remainder modulo the smaller.	Medium7	Game theoryMath	No attempts yet	0.1s	1024 MB	Judgeable
MissionIn an undirected weighted graph, find the shortest simple path from B to H that passes through E.	Medium7	GraphShortest path	No attempts yet	1s	1024 MB	Judgeable
An inexperienced slalomerHubert travels a straight line through n vertical gates; find the largest disk diameter allowing a line that passes within every gate and print d squared as a reduced fraction.	Medium7	GeometryBinary search+1	No attempts yet	0.3s	1024 MB	Judgeable
Range XORMaintain an array under range xor updates and range xor queries, both on subarrays given by index bounds.	Medium7	Bit manipulationSegment tree+2	No attempts yet	2s	512 MB	Judgeable
Hide and Seek 2Find the minimum time for Subin to reach position K using steps of minus or plus 1 and doubling, plus the number of distinct shortest action sequences.	Medium7	BFSGraph+1	No attempts yet	2s	512 MB	Judgeable
Aurora BorealisGiven sightings at distinct times and positions, find the minimum cloud length so a unit-speed interval can cover every sighting.	Medium7	GeometryBinary search+1	No attempts yet	1s	1024 MB	Judgeable
Bribing the PrisonersRelease Q prisoners from a row of P cells in the order that minimizes bribes paid to neighbors reached by the news. Find that minimum total cost.	Medium7	Dynamic programmingIntervals+1	No attempts yet	2s	512 MB	Judgeable
Finding a string with enough inversionsFind the lexicographically smallest permutation of the first N lowercase letters with at least V inversions that is not smaller than the given string S.	Medium7	BacktrackingCombinatorics+1	No attempts yet	2s	512 MB	Judgeable
Mutalisk 2Given up to 20 SCVs with health, each attack deals 9, 3, and 1 damage to three distinct SCVs; find the minimum number of attacks to destroy all of them.	Medium7	Dynamic programmingBit manipulation+1	No attempts yet	2s	512 MB	Judgeable
Distinct valid bracket subsequencesCount distinct non-empty balanced bracket strings that appear as subsequences of a given bracket string of length at most 100, modulo 1,000,000,007.	Medium7	Dynamic programmingString+2	No attempts yet	2s	512 MB	Judgeable