Problems

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Total results29,453 problems

Alike Tables
Medium5
Hash map, Matrix
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Minimum Cost Sorting
Medium5
Dynamic programming, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mod-3 Permutation
Medium5
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Solving a Cubic Equation
Medium5
Math, Number theory
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Search Suggestion
Medium5
Binary search, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
2D Max Filter
Medium5
Sliding window, Queue+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Nonogram
Medium5
Backtracking, Brute force+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Cut the List
Medium5
Dynamic programming, Intervals
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Chorus
Medium5
String matching, Binary search+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Make the target from four numbers
Medium5
Brute force, Backtracking+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Number of Locks
Medium5
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Global Warming
Medium5
Union-find, Sorting+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Tutor Simulation
Medium5
Dynamic programming, Brute force
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Sailing
Medium5
Shortest path, Graph
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Invest
Medium5
Dynamic programming
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Hole
Medium5
Dynamic programming, Matrix
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Super Phyllis
Medium5
Graph, Shortest path+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Milk Scheduling
Medium5
Greedy, Heap+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cow Baseball
Medium5
Two pointers, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cross Country Skiing
Medium5
Minimum spanning tree, Union-find+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Recording the Moolympics
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Matrix
Medium5
Matrix, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Incomparable rectangle pairs
Medium5
Sorting, Geometry+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Carpet
Medium5
Stack, Matrix
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Electronic Road Pricing (ERP)
Medium5
Shortest path, Graph+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Kansas
Medium5
Geometry, Simulation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Shortest Sailing Time
Medium5
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
String Explosion
Medium5
Stack, String matching
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
One Move from Towers of Hanoi
Medium5
Recursion, Bit manipulation+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
All Squares
Medium5
Recursion, Geometry
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rubik's Cube Solver
Medium5
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Umbrella Problem
Medium5
Dynamic programming, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Blue Gene, Jr.
Medium5
Recursion, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Removing pieces so none attack
Medium5
Brute force, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stacking Blocks
Medium5
Sorting, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Gugu
Medium5
Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Lazy Cow
Medium5
Prefix sum, Matrix
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
CSS Selector Matching
Medium5
Tree, DFS+1
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Odometer
Medium5
Brute force, Combinatorics
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fair Photography
Medium5
Prefix sum, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Club Schedule
Medium5
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Baumkuchen
Medium5
Binary search, Two pointers+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Gondola sequence check
Medium5
Simulation, Hash map+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Gondola Replacement
Medium5
Sorting, Hash map
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Vacation
Medium5
Two pointers, Prefix sum+1
No attempts yet
Time limit
5s
Memory limit
64 MB
Judgeable
Sightseeing
Medium5
Heap, Minimum spanning tree+1
No attempts yet
Time limit
3.5s
Memory limit
512 MB
Judgeable
Fuleco and the Ant
Medium5
Tree, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Andres Iniesta
Medium5
Brute force, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Erased Digit Sequence
Medium5
Brute force, String+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Senior Postmen
Medium5
Simulation, Graph+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Where's That Fuel?
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Salad Bar
Medium5
Prefix sum, Stack+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Market Shopping
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Word Ladder
Medium5
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Crossing the River
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Shark Tour
Medium5
Dynamic programming, Matrix
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Heracles and the Stables of Augeas
Medium5
Dynamic programming, Geometry
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Hotter Colder
Medium5
Binary search, Math
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Distinct Subarray GCDs
Medium5
Number theory, Dynamic programming+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Reconnaissance
Medium5
Binary search, Math
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Catalan Square
Medium5
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Opening Ceremony
Medium5
Sorting, Greedy
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Clock Photos
Medium5
Sorting, String matching
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Equator
Medium5
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Train Station Tunnel
Medium5
Simulation, Implementation
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Word Search
Medium5
String matching, Matrix+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Shops
Medium5
Dynamic programming, Bit manipulation
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Hexagonal colony
Medium5
Greedy, Geometry+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Stavitel
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cargo Spaceship Loading
Medium5
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
More or Less Accurate
Medium5
Math, String+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Jury Jeopardy
Medium5
Simulation, DFS+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
The Kth Anagram in Alphabetical Order
Medium5
Combinatorics, String
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Wet Tiles
Medium5
BFS, Matrix+1
No attempts yet
Time limit
15s
Memory limit
256 MB
Judgeable
Frame
Medium5
Math, Brute force
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Chomsky Normal Form Grammar
Medium5
Dynamic programming, Intervals
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Zeroing a Binary Sequence
Medium5
Combinatorics, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Rat Tunnel
Medium5
Minimum spanning tree, Union-find+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Continued Fraction Arithmetic
Medium5
Number theory, Math
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Domiyahtzee!
Medium5
Brute force, Simulation+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Time Warp
Medium5
Math
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Fence the vegetables
Medium5
Geometry, Math
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Intrepid climber
Medium5
Tree, DFS+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Restaurant Ratings
Medium5
Combinatorics, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Not enough electricity
Medium5
Minimum spanning tree, Union-find
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Debt
Medium5
Sorting, Prefix sum
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Floating-Point Format Conversion
Medium5
Bit manipulation, Math+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
The Binary Search Efficiency Doubter
Medium5
Math, Binary search+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Preorder Traversals
Medium5
Stack, Tree
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Travel Card
Medium5
Dynamic programming, Prefix sum
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Narrow Art Gallery
Medium5
Dynamic programming
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Ring Ring
Medium5
Geometry, Math+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Erratic Ants
Medium5
BFS, Graph+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Texas Summers
Medium5
Shortest path, Graph+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Sum of consecutive numbers
Medium5
Math, Number theory
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Wheels
Medium5
Graph, BFS+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
A Walk Together
Medium5
Dynamic programming, Simulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Check Amount Validation
Medium5
String, Simulation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cent Savings
Medium5
Dynamic programming, Prefix sum
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
GREAT + SWERC = PORTO
Medium5
Backtracking, Brute force
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Alike TablesDecide whether two tables with distinct entries match after any row and column reorderings.	Medium5	Hash mapMatrix	No attempts yet	1s	128 MB	Judgeable
Minimum Cost SortingFind the cheapest total of moved values needed to sort the array when moving one element to any position costs its value.	Medium5	Dynamic programmingSorting	No attempts yet	1s	128 MB	Judgeable
Mod-3 PermutationCount entries by index and value residues mod 3, fix directly swappable pairs first, then resolve each leftover triple with two swaps.	Medium5	GreedyMath+1	No attempts yet	1s	128 MB	Judgeable
Solving a Cubic EquationFind every distinct real root of each cubic with integer coefficients, printed in ascending order rounded to four decimals.	Medium5	MathNumber theory	No attempts yet	2s	128 MB	Judgeable
Search SuggestionFor each typed prefix, print the three highest-scoring matching cities, or the match count when more than 1000 names match.	Medium5	Binary searchString+1	No attempts yet	1s	128 MB	Judgeable
2D Max FilterFor every cell of an R by C grid, output the maximum value inside the rectangular window centered on that cell, clipped at the borders.	Medium5	Sliding windowQueue+1	No attempts yet	1s	128 MB	Judgeable
NonogramDecide whether exactly one black-and-white grid fits the given row and column run lengths and print it, else print not unique.	Medium5	BacktrackingBrute force+1	No attempts yet	3s	128 MB	Judgeable
Cut the ListSplit the list into K consecutive pieces to minimize the sum of each piece's max minus min.	Medium5	Dynamic programmingIntervals	No attempts yet	2s	128 MB	Judgeable
ChorusFor each lyric, find its longest repeated substring and list which songs contain each query as a substring of it.	Medium5	String matchingBinary search+1	No attempts yet	1s	128 MB	Judgeable
Make the target from four numbersDecide whether the first four integers can form the fifth using each exactly once with +, -, *, / and parentheses.	Medium5	Brute forceBacktracking+1	No attempts yet	1s	128 MB	Judgeable
Number of LocksCount length-n strings over heights 1 to 4 that use at least three distinct heights and have an adjacent pair differing by exactly 3.	Medium5	Dynamic programmingCombinatorics	No attempts yet	1s	128 MB	Judgeable
Global WarmingGiven column heights, find the greatest number of maximal above-water runs over all real sea levels.	Medium5	Union-findSorting+1	No attempts yet	2s	512 MB	Judgeable
Tutor SimulationChoose a sequence of teaching, training, and book-buying actions within the time limit that maximizes final cash.	Medium5	Dynamic programmingBrute force	No attempts yet	2s	512 MB	Judgeable
SailingFind the quickest sailing route on a grid with six moves, tacking costs, and blocked waypoints.	Medium5	Shortest pathGraph	No attempts yet	2s	512 MB	Judgeable
InvestChoose one of five products to buy each month, respecting minimum holding periods, to maximize the total resale value at the end.	Medium5	Dynamic programming	No attempts yet	2s	512 MB	Judgeable
HoleFind the side length of the largest all-zero square in an n by n binary grid given by the positions of its ones.	Medium5	Dynamic programmingMatrix	No attempts yet	2s	512 MB	Judgeable
Super PhyllisFind every direct reporting edge that has an alternate route through at least one other person and print those edges in sorted order.	Medium5	GraphShortest path+1	No attempts yet	2s	128 MB	Judgeable
Milk SchedulingSchedule at most one cow per time unit before its deadline to maximize total gallons of milk.	Medium5	GreedyHeap+1	No attempts yet	1s	128 MB	Judgeable
Cow BaseballCount triples of cows in increasing position whose second gap is at least the first gap and at most twice it.	Medium5	Two pointersSorting	No attempts yet	1s	128 MB	Judgeable
Cross Country SkiingFind the smallest elevation gap D that keeps every waypoint mutually reachable through adjacent cells.	Medium5	Minimum spanning treeUnion-find+1	No attempts yet	1s	512 MB	Judgeable
Recording the MoolympicsSelect the largest set of programs that two tuners can record when one tuner cannot record overlapping programs.	Medium5	GreedySorting+1	No attempts yet	1s	128 MB	Judgeable
MatrixFind row addition counts from 0 to 9 that turn matrix A into B with matching column subtraction counts and the smallest row digit string.	Medium5	MatrixMath+1	No attempts yet	2s	512 MB	Judgeable
Incomparable rectangle pairsCount the pairs of rectangles where neither fits inside the other after translation or a 90-degree rotation.	Medium5	SortingGeometry+1	No attempts yet	2s	512 MB	Judgeable
CarpetFind the largest area axis-aligned rectangle covering only clear cells in a grid with pillars.	Medium5	StackMatrix	No attempts yet	2s	1024 MB	Judgeable
Electronic Road Pricing (ERP)Find the cheapest route on a grid of roads where going straight is free, left turns cost 1, right turns cost 5, and dead-end U-turns cost 10.	Medium5	Shortest pathGraph+1	No attempts yet	2s	1024 MB	Judgeable
KansasTrack the clock-bearing driving segments and rest breaks to count breaks before the path first crosses the start, or report -1.	Medium5	GeometrySimulation+1	No attempts yet	2s	1024 MB	Judgeable
Shortest Sailing TimeFind the cheapest route from the top-left to the bottom-right of a cost grid where each turn adds 3.	Medium5	Shortest pathGraph+1	No attempts yet	1s	128 MB	Judgeable
String ExplosionRepeatedly delete every occurrence of the explosion string until none remains, printing FRULA when nothing is left.	Medium5	StackString matching	No attempts yet	2s	128 MB	Judgeable
One Move from Towers of HanoiGiven n disks and an index k, report the disk and the source and destination posts of the kth move in the classic recursive Hanoi solution.	Medium5	RecursionBit manipulation+1	No attempts yet	3s	128 MB	Judgeable
All SquaresGiven starting size k, count the nested corner squares whose border or interior holds the query point.	Medium5	RecursionGeometry	No attempts yet	1s	128 MB	Judgeable
Rubik's Cube SolverApply the listed face rotations to the unfolded cube layout and report whether each face ends up a single color.	Medium5	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
The Umbrella ProblemEach turn the lemming steps one row down while laser beams rotate, and the task asks whether any grass square in the last row is reachable alive.	Medium5	Dynamic programmingSimulation+1	No attempts yet	1s	128 MB	Judgeable
Blue Gene, Jr.Simulate the recursive mutation rules on each short alphanumeric code and print the stabilized code.	Medium5	RecursionSimulation+1	No attempts yet	1s	128 MB	Judgeable
Removing pieces so none attackRemove the fewest chess pieces from each board of up to 15 pieces so no two remaining pieces attack each other.	Medium5	Brute forceGraph+1	No attempts yet	1s	128 MB	Judgeable
Stacking BlocksReshape both towers into the V-shaped skyline with center height h at the lowest total cost of added and removed blocks.	Medium5	SortingPrefix sum+1	No attempts yet	1s	128 MB	Judgeable
GuguIdentify the English song behind lyrics written with repeated syllables and print its title in lowercase.	Medium5	Implementation	No attempts yet	1s	128 MB	Judgeable
The Lazy CowChoose the cell whose Manhattan diamond of radius K holds the most grass and output that sum.	Medium5	Prefix sumMatrix	No attempts yet	1s	128 MB	Judgeable
CSS Selector MatchingGiven a nested div document and up to five CSS selectors with descendant and child combinators, print the matching element ids in document order.	Medium5	TreeDFS+1	No attempts yet	10s	256 MB	Judgeable
OdometerCount the integers between X and Y whose decimal digits use one repeated digit except for a single different digit.	Medium5	Brute forceCombinatorics	No attempts yet	1s	128 MB	Judgeable
Fair PhotographyAfter sorting cows by position, find the widest interval with equal numbers of G and H cows, where single-breed intervals also count.	Medium5	Prefix sumHash map+1	No attempts yet	1s	128 MB	Judgeable
Club ScheduleCount attendance and key-passing schedules over N days where each day's leader attends and the key stays with attendees.	Medium5	Dynamic programmingCombinatorics	No attempts yet	1s	128 MB	Judgeable
BaumkuchenSplit the circular cake into three contiguous pieces so the smallest piece is as large as possible.	Medium5	Binary searchTwo pointers+1	No attempts yet	2s	256 MB	Judgeable
Gondola sequence checkDecide whether n observed gondola numbers could appear as consecutive passings on a circle where broken gondolas are replaced in order by numbered spares.	Medium5	SimulationHash map+1	No attempts yet	1s	256 MB	Judgeable
Gondola ReplacementGiven the n cars seen on a circular gondola line, find one possible order of breakdowns that explains the observed numbers.	Medium5	SortingHash map	No attempts yet	1s	256 MB	Judgeable
VacationFrom a start city on a line with a fixed day budget where each move or city visit costs one day, pick the contiguous block with the most attractions.	Medium5	Two pointersPrefix sum+1	No attempts yet	5s	64 MB	Judgeable
SightseeingFrom node 1, route each destination along roads to make the weakest road on the path as strong as possible.	Medium5	HeapMinimum spanning tree+1	No attempts yet	3.5s	512 MB	Judgeable
Fuleco and the AntGiven positions A and B and a U/D string encoding depth changes along a tree walk, output the tree distance between the two forks.	Medium5	TreePrefix sum+1	No attempts yet	1s	64 MB	Judgeable
Andres IniestaYou remove up to K obstacles and choose a standing cell to maximize visible cells in its row and column.	Medium5	Brute forcePrefix sum+1	No attempts yet	1s	128 MB	Judgeable
Erased Digit SequenceFind the smallest N so K consecutive integers starting at N each contain the corresponding given digit.	Medium5	Brute forceString+1	No attempts yet	1s	256 MB	Judgeable
Senior PostmenThe program replays the given stack walk on the street graph and prints each cycle it extracts in order.	Medium5	SimulationGraph+2	No attempts yet	1s	256 MB	Judgeable
Where's That Fuel?Starting with planet P's fuel, repeatedly visit affordable planets to maximize final fuel, then the number of visits.	Medium5	GreedySorting+1	No attempts yet	2s	256 MB	Judgeable
Salad BarFind the longest contiguous block of apples and oranges where oranges never fall behind apples when added from either end.	Medium5	Prefix sumStack+1	No attempts yet	3s	256 MB	Judgeable
Market ShoppingYou choose exactly k prices per query to maximize the odd total, printing -1 when no odd sum exists.	Medium5	GreedySorting+1	No attempts yet	10s	256 MB	Judgeable
Word LadderFind the shortest chain between each queried word pair where neighbors differ by one letter, printing the lexicographically first among the shortest.	Medium5	BFSGraph+1	No attempts yet	1s	256 MB	Judgeable
Crossing the RiverPick a booster range and rock hops that cross the river with the lowest range-squared plus per-jump cost.	Medium5	GreedySorting	No attempts yet	1s	256 MB	Judgeable
Shark TourSteer a car through a grid tunnel with blocked cells to collect the most sharks and print the tie-breaking action sequence.	Medium5	Dynamic programmingMatrix	No attempts yet	1s	256 MB	Judgeable
Heracles and the Stables of AugeasPick rivers whose water totals at least W so the sum of straight-line digging distances from the stable is smallest.	Medium5	Dynamic programmingGeometry	No attempts yet	1s	256 MB	Judgeable
Hotter ColderJack must find Jill's hidden number between 1 and N using only hotter, colder, or same feedback on each guess.	Medium5	Binary searchMath	No attempts yet	5s	256 MB	Judgeable
Distinct Subarray GCDsCount the distinct GCD values taken over all contiguous subarrays for each test case.	Medium5	Number theoryDynamic programming+1	No attempts yet	5s	256 MB	Judgeable
ReconnaissanceFind the minimum distance between the leading and trailing vehicles over all future times given their positions and constant velocities.	Medium5	Binary searchMath	No attempts yet	3s	256 MB	Judgeable
Catalan SquareCompute the convolution sum S_n of Catalan numbers for a given n up to 5000 and print the exact integer.	Medium5	CombinatoricsMath	No attempts yet	1s	256 MB	Judgeable
Opening CeremonyGiven each block height, find the fewest charges that clear all blocks with whole-block shots and level-wide shots.	Medium5	SortingGreedy	No attempts yet	1s	256 MB	Judgeable
Clock PhotosDecide whether two sets of hand angles on a dial coincide after rotating one photo.	Medium5	SortingString matching	No attempts yet	1s	256 MB	Judgeable
EquatorEach test case gives city profits around a circle and asks for the most profitable contiguous block, or zero when all are losses.	Medium5	Dynamic programmingArray	No attempts yet	1s	256 MB	Judgeable
Train Station TunnelThe program simulates two-way pedestrian flow with blocking and sidestep rules and outputs the tick when the last person exits.	Medium5	SimulationImplementation	No attempts yet	5s	256 MB	Judgeable
Word SearchFind each listed word in the letter grid in any of eight directions and output leftover letters, or report missing or ambiguous placements.	Medium5	String matchingMatrix+1	No attempts yet	1s	256 MB	Judgeable
ShopsPick cells with no shared side in an N by 5 profit grid to maximize the summed profit.	Medium5	Dynamic programmingBit manipulation	No attempts yet	2s	256 MB	Judgeable
Hexagonal colonyChoose hexagonal cell blocks so the exposed wall windows house at least P people with the fewest blocks.	Medium5	GreedyGeometry+2	No attempts yet	1s	256 MB	Judgeable
StavitelA cube building on a square board must match given front and right skyline heights; find the minimum and maximum possible cube counts.	Medium5	GreedySorting+1	No attempts yet	1s	256 MB	Judgeable
Cargo Spaceship LoadingYou pack items weighing powers of three to maximize total value within each capacity and print the count per dimension.	Medium5	MathGreedy	No attempts yet	1s	256 MB	Judgeable
More or Less AccurateAdd one to each negabinary number in the input and print the result without leading zeros.	Medium5	MathString+1	No attempts yet	1s	256 MB	Judgeable
Jury JeopardyReconstruct the ASCII tree maze that yields each given right-hand-rule robot walk.	Medium5	SimulationDFS+1	No attempts yet	3s	256 MB	Judgeable
The Kth Anagram in Alphabetical OrderGiven a word and rank K, print the Kth distinct anagram of the word in alphabetical order.	Medium5	CombinatoricsString	No attempts yet	1s	256 MB	Judgeable
Wet TilesCount the grid tiles reached by water spreading each minute from leaks to edge neighbors without crossing wall tiles within T minutes.	Medium5	BFSMatrix+1	No attempts yet	15s	256 MB	Judgeable
FrameYou must answer YES or NO for each of N bar lengths based on whether bars of that length tile the one-cell-thick X by Y frame.	Medium5	MathBrute force	No attempts yet	5s	256 MB	Judgeable
Chomsky Normal Form GrammarDecide whether a given string of up to 1000 lowercase letters belongs to the language generated from start symbol S by a CNF grammar.	Medium5	Dynamic programmingIntervals	No attempts yet	5s	256 MB	Judgeable
Zeroing a Binary SequenceCount ordered flip sequences of exactly K moves that turn a given binary sequence into all zeroes.	Medium5	CombinatoricsDynamic programming	No attempts yet	1s	256 MB	Judgeable
Rat TunnelPick the cheapest lanes for cameras so every closed running route holds one, and report the total cost and the longest chosen lane.	Medium5	Minimum spanning treeUnion-find+1	No attempts yet	1s	256 MB	Judgeable
Continued Fraction ArithmeticGiven two rationals as continued fractions, output the continued fractions of their sum, difference, product and quotient.	Medium5	Number theoryMath	No attempts yet	3s	256 MB	Judgeable
Domiyahtzee!Score the 12 five-dice lines of a domino-filled 5x5 grid and print the best total after at most one domino swap.	Medium5	Brute forceSimulation+1	No attempts yet	3s	256 MB	Judgeable
Time WarpGiven phrases like 'a after b', find the nearest clock time after or before the hour when the directed hand angle equals a.	Medium5	Math	No attempts yet	3s	256 MB	Judgeable
Fence the vegetablesGiven up to 100000 plant points, compute the perimeter and area of the smallest axis-aligned integer-corner fence that keeps each side 1 mm from every plant.	Medium5	GeometryMath	No attempts yet	3s	256 MB	Judgeable
Intrepid climberStarting from the root of a weighted tree, visit all marked nodes with free descents and costly climbs at minimum total energy.	Medium5	TreeDFS+1	No attempts yet	3s	256 MB	Judgeable
Restaurant RatingsCount how many nonnegative score sheets rank no better than the given sheet under total sum first and critic order second.	Medium5	CombinatoricsDynamic programming	No attempts yet	1s	256 MB	Judgeable
Not enough electricityConnect every city to exactly one of the given power plants with minimum total cable cost.	Medium5	Minimum spanning treeUnion-find	No attempts yet	1s	256 MB	Judgeable
DebtFor every group size M, choose M loans to minimize M times the largest chosen loan minus their sum, and output the total of these minima.	Medium5	SortingPrefix sum	No attempts yet	1s	256 MB	Judgeable
Floating-Point Format ConversionConvert each 8-digit hex Gould floating-point value to its IEEE 754 single-precision hex form with truncation and overflow rules.	Medium5	Bit manipulationMath+1	No attempts yet	1s	256 MB	Judgeable
The Binary Search Efficiency DoubterGiven a list length n, compute the total number of binary search loop iterations spent finding every element.	Medium5	MathBinary search+1	No attempts yet	1s	256 MB	Judgeable
Preorder TraversalsDecide whether each given number list is the preorder traversal of some binary search tree.	Medium5	StackTree	No attempts yet	1s	256 MB	Judgeable
Travel CardGiven daily bus and train ride counts, compute the cheapest mix of single fares and 1, 7, and 30 day bus and travel passes.	Medium5	Dynamic programmingPrefix sum	No attempts yet	1s	256 MB	Judgeable
Narrow Art GalleryClose exactly k rooms with no row fully closed and no diagonal closures to keep the maximum total value of open rooms.	Medium5	Dynamic programming	No attempts yet	2s	256 MB	Judgeable
Ring RingDecide if a dog crossing a road on a timed start collides with any of ten moving bicycle segments and report the gap used or the first hit.	Medium5	GeometryMath+1	No attempts yet	2s	256 MB	Judgeable
Erratic AntsGiven a recorded walk on a grid, find the fewest steps from start to end using only walked edges or their reverses.	Medium5	BFSGraph+1	No attempts yet	2s	256 MB	Judgeable
Texas SummersFind the route from the dormitory to class through shady spots that minimizes the sum of squared leg lengths, with ties broken by lexicographic index order.	Medium5	Shortest pathGraph+1	No attempts yet	2s	256 MB	Judgeable
Sum of consecutive numbersWrite each N up to 1e9 as the shortest sum of two or more consecutive positive integers, or print IMPOSSIBLE.	Medium5	MathNumber theory	No attempts yet	5s	256 MB	Judgeable
WheelsWheel 1 turns once per minute clockwise, and each wheel linked by touches turns at inverse radius ratio with alternating direction.	Medium5	GraphBFS+1	No attempts yet	1s	256 MB	Judgeable
A Walk TogetherTwo walkers follow turn-by-turn routes on a grid, and you compute the most blocks they can walk together by waiting and matching identical directed blocks.	Medium5	Dynamic programmingSimulation	No attempts yet	1s	256 MB	Judgeable
Check Amount ValidationCheck whether each English check amount follows the grammar and matches the given digit amount.	Medium5	StringSimulation+1	No attempts yet	1s	256 MB	Judgeable
Cent SavingsSplit up to 2000 item prices in order into at most d+1 consecutive groups so the sum of each group rounded to the nearest 10 cents is smallest.	Medium5	Dynamic programmingPrefix sum	No attempts yet	5s	512 MB	Judgeable
GREAT + SWERC = PORTOCount the assignments of distinct digits to letters that make the word sum correct with nonzero leading letters.	Medium5	BacktrackingBrute force	No attempts yet	2s	256 MB	Judgeable