Problems

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Total results29,425 problems

Backpack
Medium6
Dynamic programming, Tree+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Shuffling Cards
Medium6
Math, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rooks
Medium6
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Kangaroos
Medium6
Intervals, Sorting+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Road Network 2
Medium6
Tree, Combinatorics+1
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Exam
Medium6
Geometry, Intervals+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Prime Prime Power
Medium6
Number theory, Math+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Coins
Medium6
Prefix sum, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Acyclic Decomposition
Medium6
Graph, Greedy+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Drilling
Medium6
Dynamic programming, Binary search+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Chess
Medium6
Combinatorics, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Colouring
Medium6
Graph, Union-find+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Bug
Medium6
Graph, Shortest path+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Crossing Diagonals
Medium6
Sorting, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Chessboard
Medium6
Sorting, Hash map+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Safe
Medium6
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Reconstruction of Byteland
Medium6
Math, Number theory+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Conference
Medium6
Dynamic programming, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sheets
Medium6
Math, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Brackets
Medium6
Combinatorics, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Inversions
Medium6
Dynamic programming, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Speed Limits
Medium6
Array, Prefix sum+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Round-Table Handshakes
Medium6
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Contour Lines
Medium6
Geometry, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Truth Fraction of a Formula
Medium6
Bit manipulation, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Jan
Medium6
String, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Polynomial
Medium6
Math, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Binary Robots
Medium6
Greedy, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Matchings
Medium6
Dynamic programming, Tree+2
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Earthquake
Medium6
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Genomes
Medium6
Graph, Topological sort+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Map
Medium6
Prefix sum, Matrix+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
NumberEater
Medium6
Hash map, Array+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bit Shark
Medium6
String, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Signed Binary Expansion
Medium6
Dynamic programming, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bracket Expressions
Medium6
Stack, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Race
Medium6
Sliding window, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Cosmic Pursuit
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Magic Square
Medium6
Math, Matrix
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Balancing the Scale
Medium6
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Klasy
Medium6
Simulation, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Aquapark
Medium6
Prefix sum, Matrix
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Klocki
Medium6
Divide and conquer, Sorting+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Spaceships
Medium6
Sorting, Binary search
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Triangle Sticks
Medium6
Sorting, Brute force+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Diamond Cipher
Medium6
Math, String+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
One-Armed Bandit
Medium6
Hash map, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bajhattan Panorama
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Operations
Medium6
Segment tree
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Aquarium
Medium6
Simulation, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tower 2
Medium6
Segment tree, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Domino
Medium6
Greedy, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Clocks
Medium6
Sorting, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Number of Longest Increasing Subsequences
Medium6
Dynamic programming, Segment tree
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Longest Common Increasing Subsequence
Medium6
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Metro
Medium6
Greedy, Simulation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Paper Folding
Medium6
Dynamic programming, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Eurozwrotnica
Medium6
Queue, Greedy
No attempts yet
Time limit
2.5s
Memory limit
128 MB
Judgeable
Why Do They Sing?
Medium6
Union-find, Geometry
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Paweł i Gaweł
Medium6
Game theory, Dynamic programming+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Bridges
Medium6
Intervals, Topological sort+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Queries
Medium6
Segment tree, Sorting
No attempts yet
Time limit
10s
Memory limit
128 MB
Judgeable
Domino
Medium6
Dynamic programming, Binary search+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cookies
Medium6
Sorting, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Program
Medium6
Binary search, Intervals+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Maneuvers
Medium6
Sorting, Greedy
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Triple Products
Medium6
Segment tree, Math+1
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Stained Glass
Medium6
Hash map, Combinatorics+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Reservoir
Medium6
Shortest path, Heap+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Formula Race
Medium6
Dynamic programming, Shortest path
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Similar Cities
Medium6
BFS, Graph+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Art class
Medium6
Simulation, Matrix+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Low Power
Medium6
Binary search, Greedy+1
No attempts yet
Time limit
4s
Memory limit
256 MB
Judgeable
Pattern Lock
Medium6
Backtracking, Graph+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Bar Arrangement
Medium6
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Leet
Medium6
Backtracking, String+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Binary Search Tree
Medium6
Combinatorics, Tree+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Jump
Medium6
Math, Simulation+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Cycle
Medium6
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hubble Space Telescope
Medium6
Binary search, Geometry+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Binary Search Tree 2
Medium6
Combinatorics, Tree+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Signals
Medium6
String matching, Recursion+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Turtle Graphics
Medium6
Simulation, Stack+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Period
Medium6
Dynamic programming, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cannon's Move
Medium6
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Utility Poles
Medium6
Math, Binary search+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
People like people
Medium6
Graph, Queue+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Moving Pegs
Medium6
BFS, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sum of Fibonacci Numbers
Medium6
Greedy, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Largest Square
Medium6
Geometry, Hash map+1
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Cube of a Graph
Medium6
Graph, DFS+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Practice Season
Medium6
Dynamic programming, String matching
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Cube
Medium6
Dynamic programming, Recursion
No attempts yet
Time limit
10s
Memory limit
128 MB
Judgeable
Shoe-print
Medium6
Geometry
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Delivery
Medium6
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Conference Table
Medium6
Graph, DFS
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Golf Courses
Medium6
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pile of Cubes
Medium6
Greedy, Matrix
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
KTX
Medium6
Stack, Backtracking+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mine Clearing
Medium6
Sliding window, Sorting+1
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
BackpackChoose a set of items whose total mass is at most p, where each chosen item requires its named lower-indexed prerequisite to be chosen too.	Medium6	Dynamic programmingTree+1	No attempts yet	1s	128 MB	Judgeable
Shuffling CardsDecide whether permutation b equals some power a^k of permutation a with k greater than 1.	Medium6	MathCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
RooksComplete a partially filled n by n board to a full non-attacking rook placement, choosing the lexicographically smallest completion.	Medium6	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
KangaroosFor each lens interval, find the longest contiguous block of sighting intervals that all overlap it.	Medium6	IntervalsSorting+2	No attempts yet	5s	128 MB	Judgeable
Road Network 2Count the labeled trees that realize a prescribed degree sequence, or report that none exist, with n up to two million.	Medium6	TreeCombinatorics+1	No attempts yet	5s	128 MB	Judgeable
ExamGiven n equal-size axis-aligned rectangles dropped in order, report the indices of sheets whose interior no later sheet covers.	Medium6	GeometryIntervals+2	No attempts yet	5s	128 MB	Judgeable
Prime Prime PowerGiven n and k, print the k-th smallest number of the form p^q with both p and q prime that is strictly greater than n.	Medium6	Number theoryMath+2	No attempts yet	5s	128 MB	Judgeable
CoinsGiven a string of O and R tosses, find the longest substring where the number of O equals k times the number of R.	Medium6	Prefix sumHash map+1	No attempts yet	1s	128 MB	Judgeable
Acyclic DecompositionGiven a directed graph, find the minimum number of acyclic subgraphs needed to partition all its edges.	Medium6	GraphGreedy+2	No attempts yet	2s	512 MB	Judgeable
DrillingGiven drilling costs at n positions along a segment, find the minimum worst-case total time to locate the reservoir boundary using adaptive queries.	Medium6	Dynamic programmingBinary search+2	No attempts yet	1s	128 MB	Judgeable
ChessAn n by n board with n rooks, at most one per row and column, and the placement unchanged after a 90 degree rotation is given. Count the number of such placements for n up to 50000.	Medium6	CombinatoricsMath+1	No attempts yet	2s	512 MB	Judgeable
ColouringCount the two-colourings of a 2 by n grid such that no column and no pair of equal numbers share a colour.	Medium6	GraphUnion-find+1	No attempts yet	2s	512 MB	Judgeable
BugFind the shortest route from city 1 to city n whose total length is odd, or report 0 if none exists.	Medium6	GraphShortest path+1	No attempts yet	1s	128 MB	Judgeable
Crossing DiagonalsCount crossing pairs among m chosen diagonals of a regular n-gon, ignoring diagonals that only share a vertex.	Medium6	SortingPrefix sum+1	No attempts yet	1s	128 MB	Judgeable
ChessboardGiven up to 200,000 pieces on an m by m board, count for each piece how many empty squares it can capture in one move.	Medium6	SortingHash map+2	No attempts yet	1s	128 MB	Judgeable
SafeGiven a word and one rotation offset per wheel, find the minimum total turns to make all wheels display the same word.	Medium6	StringImplementation+2	No attempts yet	1s	128 MB	Judgeable
Reconstruction of BytelandGiven n codes, check that they are pairwise distinct, every pair shares a common factor, and every majority subset has gcd 1.	Medium6	MathNumber theory+2	No attempts yet	1s	128 MB	Judgeable
ConferenceGiven per-presentation ticket prices, room capacity and room rent, and group reservations, choose how many tickets to cancel to maximize revenue minus rent.	Medium6	Dynamic programmingGreedy+1	No attempts yet	1s	128 MB	Judgeable
SheetsStarting from sheets 1..n, each step merges the first k into their sum appended at the end; report the sum written during the r-th step.	Medium6	MathSimulation+2	No attempts yet	1s	128 MB	Judgeable
BracketsGiven n and k, print the k-th correct bracket sequence of length 2n in lexicographic order.	Medium6	CombinatoricsDynamic programming+1	No attempts yet	1s	128 MB	Judgeable
InversionsCount permutations of size n that have exactly k inversions, modulo 30011, using the Mahonian number recurrence with a sliding window over prefix sums.	Medium6	Dynamic programmingCombinatorics+2	No attempts yet	1s	128 MB	Judgeable
Speed LimitsGiven speed limits on intervals of a highway plus a car's top speed, pick the single limit whose removal maximizes total satisfaction (distance times speed).	Medium6	ArrayPrefix sum+2	No attempts yet	1s	128 MB	Judgeable
Round-Table HandshakesCount matchings on an n-person cycle where each person shakes at most one neighbor's hand, and print the count modulo 10.	Medium6	Dynamic programmingCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
Contour LinesGiven sets of axis-parallel polygons, decide whether each set can be ordered so every polygon lies inside the next.	Medium6	GeometrySorting+1	No attempts yet	1s	128 MB	Judgeable
Truth Fraction of a FormulaGiven a DNF formula over n variables, count the valuations that satisfy at least one clause and print the fraction over 2^n as an exact decimal.	Medium6	Bit manipulationCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
JanSplit a given lowercase word into the fewest pieces, each of which is lexicographically smaller than all of its nontrivial rotations, and print one valid minimum split.	Medium6	StringGreedy+2	No attempts yet	1s	128 MB	Judgeable
PolynomialGiven a degree-n polynomial's values at 0 through n, compute its value at n+1.	Medium6	MathPrefix sum+1	No attempts yet	1s	128 MB	Judgeable
Binary RobotsAssign each chosen robot to one distinct job it can do, with at most two jobs per robot, to maximize total rental price.	Medium6	GreedyGraph+2	No attempts yet	1s	128 MB	Judgeable
MatchingsGiven a tree, compute the size of its maximum matching and count how many maximum matchings exist, modulo m.	Medium6	Dynamic programmingTree+2	No attempts yet	3s	128 MB	Judgeable
EarthquakeCount the integer points (x,y) with x≥0, y≥0 and Ax+By≤C for given positive A, B, C.	Medium6	MathNumber theory+1	No attempts yet	1s	128 MB	Judgeable
GenomesFind the length of the longest common subsequence of up to 20 permutations of size up to 500.	Medium6	GraphTopological sort+1	No attempts yet	1s	128 MB	Judgeable
MapGiven an n by m grid and q queries, each comparing two h by w subrectangles, decide if at most k corresponding cells differ.	Medium6	Prefix sumMatrix+1	No attempts yet	1s	128 MB	Judgeable
NumberEaterCount the number of distinct value sets obtainable as the set of a contiguous subarray of the given sequence.	Medium6	Hash mapArray+1	No attempts yet	1s	128 MB	Judgeable
Bit SharkFind the length of the string left after repeatedly deleting the second half of any even-length palindrome, choosing deletions to maximize bits eaten.	Medium6	StringGreedy+1	No attempts yet	1s	128 MB	Judgeable
Signed Binary ExpansionGiven a decimal integer with up to 500 digits, find the smallest possible count of nonzero digits in a signed binary expansion.	Medium6	Dynamic programmingGreedy+2	No attempts yet	1s	128 MB	Judgeable
Bracket ExpressionsThe task is to count substrings of a bracket string that are correct bracket sequences.	Medium6	StackDynamic programming	No attempts yet	1s	512 MB	Judgeable
RaceFind the length-m segment of the road that minimizes total riding time under piecewise constant speed limits.	Medium6	Sliding windowPrefix sum+1	No attempts yet	1s	512 MB	Judgeable
Cosmic PursuitYou order integer-time shots so each pursuer is destroyed before it reaches your ship.	Medium6	GreedySorting+1	No attempts yet	1s	512 MB	Judgeable
Magic SquareFill in the n missing cells, one per row and column, so all rows, columns, and both diagonals add to the same total.	Medium6	MathMatrix	No attempts yet	1s	512 MB	Judgeable
Balancing the ScaleRemove the fewest bricks from the tops of the towers so the total weight on the left pan equals the total on the right.	Medium6	Dynamic programming	No attempts yet	1s	512 MB	Judgeable
KlasyPrint the requested subrectangle of an n by n grid filled in spiral order from a corner by a walk that turns only right or only left.	Medium6	SimulationMath+1	No attempts yet	1s	512 MB	Judgeable
AquaparkSum the grid values inside the Manhattan diamond of radius l_i around each lifeguard.	Medium6	Prefix sumMatrix	No attempts yet	1s	512 MB	Judgeable
KlockiChoose at most k of the n blocks so their total mass is as large as possible without exceeding s.	Medium6	Divide and conquerSorting+1	No attempts yet	1s	512 MB	Judgeable
SpaceshipsThe program counts triples with one module from each factory whose fuel-weighted range tops half the best possible range.	Medium6	SortingBinary search	No attempts yet	1s	512 MB	Judgeable
Triangle SticksThe program keeps the largest subset of up to 30000 sticks with lengths 1 to 500 in which any three sticks form a non-degenerate triangle.	Medium6	SortingBrute force+1	No attempts yet	1s	512 MB	Judgeable
Diamond CipherThe program writes each password as signed powers of three and lists the Up and Down switches.	Medium6	MathString+1	No attempts yet	1s	512 MB	Judgeable
One-Armed BanditFind the rotation of three symbol reels that maximizes the number of rows showing the same symbol three times.	Medium6	Hash mapMath	No attempts yet	1s	128 MB	Judgeable
Bajhattan PanoramaGiven row maxima and column maxima, test whether any grid fits them and compute the largest possible total height.	Medium6	GreedySorting+1	No attempts yet	1s	128 MB	Judgeable
OperationsMaintain an array of values below k under interval cyclic increments and answer interval sums.	Medium6	Segment tree	No attempts yet	1s	128 MB	Judgeable
AquariumFor each query, decide if a fish survives x days when each day fish act largest first and each eats the smallest smaller fish to gain half its mass.	Medium6	SimulationSorting+2	No attempts yet	1s	128 MB	Judgeable
Tower 2Each visitor climbs while taller than each step and stops below the previous visitor, and you report the highest step each one reaches.	Medium6	Segment treeSimulation	No attempts yet	1s	128 MB	Judgeable
DominoChoose the smallest chain from the first to the last domino where each kept tile is taller than the distance to the next kept tile.	Medium6	GreedyPrefix sum+1	No attempts yet	1s	128 MB	Judgeable
ClocksPick one time every clock can show so the total forward movement from the current readings is as small as possible.	Medium6	SortingPrefix sum+1	No attempts yet	1s	128 MB	Judgeable
Number of Longest Increasing SubsequencesCount how many strictly increasing subsequences of the given sequence attain the maximum possible length, modulo m.	Medium6	Dynamic programmingSegment tree	No attempts yet	1s	128 MB	Judgeable
Longest Common Increasing SubsequenceFind the length of the longest strictly increasing sequence that is a subsequence of both given sequences.	Medium6	Dynamic programmingArray	No attempts yet	1s	128 MB	Judgeable
MetroTwo trains depart opposite ends of a single-track line and may wait at stations so they cross only at a two-platform station; minimize the later arrival time.	Medium6	GreedySimulation	No attempts yet	2s	128 MB	Judgeable
Paper FoldingRepeatedly fold the left part of a binary strip over the right where symbols match and find the shortest reachable length.	Medium6	Dynamic programmingString+1	No attempts yet	1s	128 MB	Judgeable
EurozwrotnicaDecide whether the arriving train order can be split across two FIFO tracks so all trains leave in increasing order.	Medium6	QueueGreedy	No attempts yet	2.5s	128 MB	Judgeable
Why Do They Sing?Decide whether a path from the bottom edge to the top edge of a rectangle avoids every given singing circle.	Medium6	Union-findGeometry	No attempts yet	1s	128 MB	Judgeable
Paweł i GawełTwo players alternate moving a pawn across a grid, swapping floors whenever it enters a marked cell, each trying to hold the upper floor at the end.	Medium6	Game theoryDynamic programming+1	No attempts yet	3s	128 MB	Judgeable
BridgesAssign each pair a distinct height so the number of vertical-horizontal crossings is minimal and output the bridges from lowest to highest.	Medium6	IntervalsTopological sort+1	No attempts yet	2s	128 MB	Judgeable
QueriesMaintain a point set under deletions and report the leftmost point within S below the current highest y, breaking ties by higher y.	Medium6	Segment treeSorting	No attempts yet	10s	128 MB	Judgeable
DominoTopple one domino left or right and count how many fall in the longest chain reaction.	Medium6	Dynamic programmingBinary search+1	No attempts yet	1s	128 MB	Judgeable
CookiesBoth players take the best remaining cookie in turn with Zbyszek starting, and you add at most one cookie of any quality to minimize his total minus Hektor's.	Medium6	SortingPrefix sum+1	No attempts yet	2s	128 MB	Judgeable
ProgramCount the starting values from 1 to M that reach exactly A after running the given add, subtract, multiply, and floor-divide program.	Medium6	Binary searchIntervals+1	No attempts yet	1s	128 MB	Judgeable
ManeuversSoldiers cross a river and then wire one at a time, and you order them to minimize total completion time.	Medium6	SortingGreedy	No attempts yet	2s	128 MB	Judgeable
Triple ProductsSupport point updates on an array and report, for each queried interval, the sum of products over all triples of distinct positions.	Medium6	Segment treeMath+1	No attempts yet	5s	128 MB	Judgeable
Stained GlassGiven N lines with fixed directions that may be shifted freely, arrange them to maximize the number of regions and output that maximum.	Medium6	Hash mapCombinatorics+2	No attempts yet	2s	128 MB	Judgeable
ReservoirRaise water from the pump across edge-adjacent cells of bounded height to the highest level that floods no tree, and report the flooded count.	Medium6	Shortest pathHeap+1	No attempts yet	1s	128 MB	Judgeable
Formula RaceFinish exactly N laps with refueling pit stops and two tire types, both used at least once, in minimum total time.	Medium6	Dynamic programmingShortest path	No attempts yet	1s	128 MB	Judgeable
Similar CitiesFind the shortest digit string that reaches a house from the town hall in exactly one of two given directed labeled graphs.	Medium6	BFSGraph+1	No attempts yet	2s	128 MB	Judgeable
Art classGiven red, green, and blue values for each pixel of a painting, decide which of four described art styles it belongs to and print its number.	Medium6	SimulationMatrix+1	No attempts yet	5s	256 MB	Judgeable
Low PowerSort 2nk batteries into groups of k and pair the group minima into n machines to minimize the largest pair gap.	Medium6	Binary searchGreedy+1	No attempts yet	4s	256 MB	Judgeable
Pattern LockGiven the unit-segment graph left by an Android pattern, find a valid pattern of at least four dots that draws exactly it.	Medium6	BacktrackingGraph+1	No attempts yet	3s	128 MB	Judgeable
Bar ArrangementCount permutations of 1 to n with exactly l left-to-right maxima and r right-to-left maxima for each test case.	Medium6	Dynamic programmingCombinatorics	No attempts yet	1s	256 MB	Judgeable
LeetDecide whether the plain word can be split so each distinct letter maps to one fixed leet block of length at most k.	Medium6	BacktrackingString+1	No attempts yet	2s	128 MB	Judgeable
Binary Search TreeCount the insertion orders that build the same binary search tree as the given permutation.	Medium6	CombinatoricsTree+1	No attempts yet	2s	256 MB	Judgeable
JumpYou remove every k-th number around a circle and print the last three removed numbers for each test case.	Medium6	MathSimulation+1	No attempts yet	3s	128 MB	Judgeable
CycleSimulate the given ICPC program with pipelined fetch, decode, and execute stages and report total cycles, or error on 16-bit overflow.	Medium6	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Hubble Space TelescopeFind the earliest time t between 0 and 100000 that minimizes the largest distance from the star alpha to the other moving stars.	Medium6	Binary searchGeometry+1	No attempts yet	1s	128 MB	Judgeable
Binary Search Tree 2Count the permutations of 1 to N that build the same binary search tree as the given permutation.	Medium6	CombinatoricsTree+1	No attempts yet	1s	128 MB	Judgeable
SignalsCompare the signal sets generated by two series-parallel circuit expressions and print whether they are equal, nested, disjoint or overlapping.	Medium6	String matchingRecursion+1	No attempts yet	1s	128 MB	Judgeable
Turtle GraphicsSimulate the direction-digit moves, erasing each loop or overlap as it forms, then report the remaining segment count and total length.	Medium6	SimulationStack+2	No attempts yet	1s	128 MB	Judgeable
PeriodSplit string x into pieces to minimize the largest edit distance between y and any piece.	Medium6	Dynamic programmingString	No attempts yet	1s	128 MB	Judgeable
Cannon's MoveMove the cannon by jumping over exactly one piece per move to capture the king in the fewest moves.	Medium6	BFSGraph+1	No attempts yet	1s	128 MB	Judgeable
Utility PolesPick a positive integer gap d so poles starting at given positions move the least total distance to land on multiples of d with the first pole fixed at zero.	Medium6	MathBinary search+1	No attempts yet	1s	128 MB	Judgeable
People like peopleFrom each voter list of up to three liked students, find the largest group where everyone voted, likes only members, and is liked by a member.	Medium6	GraphQueue+1	No attempts yet	1s	128 MB	Judgeable
Moving PegsJump pegs over lines of pegs on a 15-hole triangle to leave one peg in the starting hole in the fewest moves.	Medium6	BFSBrute force+1	No attempts yet	1s	128 MB	Judgeable
Sum of Fibonacci NumbersFor each test case with n up to 1,000,000,000, print the fewest distinct Fibonacci numbers that sum to n in increasing order.	Medium6	GreedyMath	No attempts yet	1s	128 MB	Judgeable
Largest SquareGiven N points on a plane, find the area of the largest square with all four vertices among the points, or 0 when no square exists.	Medium6	GeometryHash map+1	No attempts yet	10s	256 MB	Judgeable
Cube of a GraphCount vertices, adjacent pairs, and triangles whose incident edges are all nontrivial bridges in a connected graph.	Medium6	GraphDFS+1	No attempts yet	1s	128 MB	Judgeable
Practice SeasonBoth teams insert rest days into their fixed city orders to minimize combined stadium and hotel costs.	Medium6	Dynamic programmingString matching	No attempts yet	2s	128 MB	Judgeable
CubeCut a W by L by H integer block into integer-sided cubes with the fewest cuts and output the number of cubes.	Medium6	Dynamic programmingRecursion	No attempts yet	10s	128 MB	Judgeable
Shoe-printDecide whether two clockwise point sequences describe the same shape up to rotation and translation, without reflection.	Medium6	Geometry	No attempts yet	1s	128 MB	Judgeable
DeliveryMerge two ordered delivery lists starting from the origin to minimize total Euclidean travel distance without returning.	Medium6	Dynamic programming	No attempts yet	1s	128 MB	Judgeable
Conference TableDecide whether pairs of majors from each university can sit in a ring so paired researchers sit together and neighbors share a major.	Medium6	GraphDFS	No attempts yet	1s	128 MB	Judgeable
Golf CoursesPick course sites and assign every client to a built course to minimize building plus connection costs within capacities.	Medium6	Dynamic programmingSorting+1	No attempts yet	1s	128 MB	Judgeable
Pile of CubesFind the largest number of cubes in a gravity-respecting pile that matches the given top, front, and right views, or report -1 when no pile fits.	Medium6	GreedyMatrix	No attempts yet	1s	128 MB	Judgeable
KTXDecide whether a departure permutation can be reordered into ascending grade order using a direct main line and two LIFO bypass tracks.	Medium6	StackBacktracking+1	No attempts yet	1s	128 MB	Judgeable
Mine ClearingFind the most mines covered by one axis-aligned 10 by 10 square placed anywhere on the site.	Medium6	Sliding windowSorting+1	No attempts yet	10s	512 MB	Judgeable