Problems

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Total results29,455 problems

Subsets
Medium5
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Divided Fractals
Medium5
Recursion, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pattern Generator
Medium5
Backtracking, Recursion+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
All Roads Lead Where?
Medium5
Tree, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
King Thrór's Gold
Medium5
Dynamic programming, Backtracking+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Maximum Damage
Medium5
Prefix sum, Brute force+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Tree Cutting
Medium5
Tree, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Strip
Medium5
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Wonderful Fours
Medium5
Brute force, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Journey of a Knight
Medium5
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Gears
Medium5
Math, Number theory+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tax System
Medium5
Prefix sum, Binary search+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Making test data 5
Medium5
Graph, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Millionaire and the Orphans
Medium5
Probability, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Geocaching Coordinates
Medium5
Brute force, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Mõttemeister
Medium5
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Polygon Area
Medium5
Geometry, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tähekabe
Medium5
Backtracking, DFS+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Go-Kart
Medium5
Binary search, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sawtooth Sequence
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Animals
Medium5
Intervals, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Courier
Medium5
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Chocolate
Medium5
Matrix, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Railway Connection
Medium5
Minimum spanning tree, Union-find+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Metro
Medium5
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hey, Pay Day!
Medium5
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Balanced Chemical Equations
Medium5
Math, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Spacecraft Malfunction
Medium5
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Parentheses Encoding Conversion
Medium5
Stack, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dynamic Declaration Language (DDL)
Medium5
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Space Ant
Medium5
Geometry, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Wooden Sticks
Medium5
Sorting, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Flip and Shift
Medium5
Math, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Transportation
Medium5
Backtracking, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Joseph
Medium5
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Repeated Permutation Cipher
Medium5
Array, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Card Game Cheater
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Investment
Medium5
Dynamic programming, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Gunman
Medium5
Geometry, Binary search+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Alternative Scale of Notation
Medium5
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Divisibility
Medium5
Dynamic programming, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Highways
Medium5
Minimum spanning tree, Union-find
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
False Coin
Medium5
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Spell Checker
Medium5
String, Hash map+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bin Packing
Medium5
Greedy, Two pointers+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dancers
Medium5
Sorting, Geometry+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Playground Hideout
Medium5
Shortest path, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Olympic Games
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Diophantus of Alexandria
Medium5
Number theory, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Relocation
Medium5
Dynamic programming, Binary search+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Number Tricks
Medium5
Number theory, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dart Scoring
Medium5
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
A Bug's Life
Medium5
Union-find, Graph
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Heavy Transportation
Medium5
Graph, Minimum spanning tree+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Magic Trick
Medium5
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Formula Racing
Medium5
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cocktails
Medium5
Simulation, Hash map+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Ship Journey
Medium5
Simulation, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tomatoes
Medium5
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Catching Fish
Medium5
Brute force, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Factory
Medium5
Sorting, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Balanced Change
Medium5
Dynamic programming, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Reconstructing Binary Trees
Medium5
Tree, Recursion+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Traffic Engineering
Medium5
Graph, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Paying the Dinner Bill
Medium5
Greedy, Math+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Betting Sets
Medium5
Dynamic programming, Bit manipulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Apocalyptic Alignment
Medium5
Dynamic programming, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dual Priority Queue
Medium5
Heap, Implementation
No attempts yet
Time limit
6s
Memory limit
256 MB
Judgeable
Go
Medium5
Graph, BFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Game Dice
Medium5
Dynamic programming, Probability+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Saruman's Army
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Football
Medium5
Dynamic programming, Probability+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tic-Tac-Toe
Medium5
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Nim
Medium5
Game theory, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Polling Stations
Medium5
Graph, Greedy
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Railway
Medium5
Tree, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Three Bit Computer
Medium5
Dynamic programming, Greedy
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Deepest Station
Medium5
Geometry, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Outlets
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Digit Sum Over a Range
Medium5
Math, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Avoiding Financial Nightmare
Medium5
Binary search, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
No Pause Telegraph
Medium5
Dynamic programming, String+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Arm Wrestling Tournament
Medium5
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Romantic Date
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Random Gap
Medium5
Simulation, Hash map+2
No attempts yet
Time limit
4s
Memory limit
128 MB
Judgeable
Nearest number - 2
Medium5
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Network Saboteur
Medium5
Brute force, Backtracking+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Binary Witch
Medium5
String, String matching+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Decision
Medium5
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Skyscrapers
Medium5
Sorting, Array+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Pearls
Medium5
Dynamic programming, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tiling Verification
Medium5
Geometry, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Afternoon Tea
Medium5
Dynamic programming, Math+1
No attempts yet
Time limit
3s
Memory limit
32 MB
Judgeable
Sunny Island
Medium5
Greedy, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Grandparents
Medium5
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cookie Monster
Medium5
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Reversing a Snake on a Complete Graph
Medium5
Graph, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Very Dirty Chain
Medium5
String, Two pointers
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Chess Player's Day
Medium5
Graph, Greedy+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
The History of Cotton
Medium5
Combinatorics, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
SubsetsGiven inequalities where a set name contains either an element or another set name, find each named set's minimal required elements.	Medium5	GraphDFS+2	No attempts yet	1s	128 MB	Judgeable
Divided FractalsPrint a rectangle of an iterated square fractal, with rows numbered bottom to top and cells joined by spaces.	Medium5	RecursionImplementation+2	No attempts yet	1s	128 MB	Judgeable
Pattern GeneratorFor each (n, k) pair, print all n-bit strings with exactly k ones in decreasing numeric order, separated by blank lines.	Medium5	BacktrackingRecursion+2	No attempts yet	1s	128 MB	Judgeable
All Roads Lead Where?Given a tree of cities rooted at Rome and query pairs, print the unique shortest path between each pair as the first letters of the cities on the route.	Medium5	TreeDFS+2	No attempts yet	1s	128 MB	Judgeable
King Thrór's GoldCount the ways to choose exactly k distinct bar values summing to T, and list all solutions in lexicographic order when there are at most 20.	Medium5	Dynamic programmingBacktracking+2	No attempts yet	1s	128 MB	Judgeable
Maximum DamageOn a grid with obstacles, orcs, and blank cells, pick at most T blank cells as stations so the total number of orcs within Manhattan distance R is maximized.	Medium5	Prefix sumBrute force+1	No attempts yet	1s	512 MB	Judgeable
Tree CuttingOn a tree of N nodes, print every node whose removal leaves each connected piece with at most floor(N/2) nodes, or NONE.	Medium5	TreeDFS+2	No attempts yet	1s	128 MB	Judgeable
StripGiven a strip of length n, fold it along k given creases in order and report the final length, where n can have up to 18 digits.	Medium5	ImplementationSimulation+1	No attempts yet	1s	128 MB	Judgeable
Wonderful FoursGiven five digits, count unordered triples of distinct permutations (no leading zero) whose sum is a different valid permutation of the same digits.	Medium5	Brute forceCombinatorics+2	No attempts yet	1s	128 MB	Judgeable
Journey of a KnightGiven an n by m board, find the minimum number of knight moves from cell (1,1) to cell (i,j), or report that it is unreachable.	Medium5	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
GearsCount how many distinct fractions a/b exist with both a and b in the range M to N.	Medium5	MathNumber theory+2	No attempts yet	1s	1024 MB	Judgeable
Tax SystemEach client's income is taxed through N progressive brackets with given widths and rates; compute the total tax for M clients, printed to two decimals.	Medium5	Prefix sumBinary search+2	No attempts yet	1s	1024 MB	Judgeable
Making test data 5Print a fixed chain graph with self-loops and queries so that ModifiedDijkstra stays under the counter limit while OptimizedBellmanFord exceeds it.	Medium5	GraphShortest path+2	No attempts yet	1s	128 MB	Judgeable
The Millionaire and the OrphansGiven three orphanages with fixed basket areas and children counts, compute the expected total gift value each orphanage catches as gifts are thrown in order.	Medium5	ProbabilityMath+1	No attempts yet	1s	1024 MB	Judgeable
Geocaching CoordinatesGiven a coordinate formula with lowercase letter slots and rules for each variable's allowed values, print every distinct resulting coordinate in lexicographic order.	Medium5	Brute forceCombinatorics+2	No attempts yet	1s	1024 MB	Judgeable
MõttemeisterGiven several guesses and their correct-digit counts A and position counts B, list every 4-digit secret number consistent with all clues.	Medium5	Brute forceImplementation+2	No attempts yet	1s	1024 MB	Judgeable
Polygon AreaGiven a grid-aligned orthogonally convex polygon as a string of unit moves, compute its area.	Medium5	GeometryImplementation+1	No attempts yet	1s	1024 MB	Judgeable
TähekabeOn an N x N letter grid, decide for each of up to 10 query words whether a simple path from the start cell spells it, without reusing a cell.	Medium5	BacktrackingDFS+2	No attempts yet	1s	1024 MB	Judgeable
Go-KartFind the smallest fuel-tank capacity that lets a kart refuel at given stations and travel at least K kilometers.	Medium5	Binary searchGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Sawtooth SequenceGiven N distinct numbers, arrange all of them into a zigzag sequence and output the lexicographically smallest such arrangement.	Medium5	GreedySorting+2	No attempts yet	1s	1024 MB	Judgeable
AnimalsGiven N daily active intervals, some crossing midnight, find whether all overlap at some moment and output the longest common sub-interval.	Medium5	IntervalsImplementation+2	No attempts yet	1s	1024 MB	Judgeable
CourierSimulate orders arriving over time: assign each to the free courier who delivers fastest, or drop it if all couriers are busy, and total each courier's earnings.	Medium5	SimulationImplementation+2	No attempts yet	1s	1024 MB	Judgeable
ChocolateGiven an M by N grid of labels, decide whether every label occupies exactly one solid axis-aligned rectangle.	Medium5	MatrixImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Railway ConnectionGiven existing rail links and city flows, find the minimum cost to connect all cities, where an edge costs the product of its endpoint flows.	Medium5	Minimum spanning treeUnion-find+2	No attempts yet	1s	1024 MB	Judgeable
MetroGiven the intervals between adjacent trains, find the wait time for each train so every gap becomes M with the smallest total waiting.	Medium5	GreedyMath+1	No attempts yet	1s	1024 MB	Judgeable
Hey, Pay Day!Given machine records and order-only watchman logs for each day, compute each worker's minimum and maximum possible total presence time.	Medium5	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Balanced Chemical EquationsGiven an unbalanced chemical equation not exceeding 9 of each molecule, find positive single-digit coefficients that balance it and minimize the concatenated number, or report IMPOSSIBLE.	Medium5	MathBrute force+1	No attempts yet	1s	128 MB	Judgeable
Spacecraft MalfunctionGiven each unit's check reports on two others, exactly one faulty unit, and a faulty unit may lie, find the unique faulty unit or print impossible.	Medium5	Brute forceImplementation+2	No attempts yet	1s	128 MB	Judgeable
Parentheses Encoding ConversionGiven the P-sequence encoding of a well-formed parenthesis string, compute its W-sequence encoding.	Medium5	StackSimulation+1	No attempts yet	1s	128 MB	Judgeable
Dynamic Declaration Language (DDL)Simulate a tiny language with dynamic variable declarations, jumps, and increments, printing a repeated-declaration or undeclared-reference error each time one occurs.	Medium5	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Space AntGiven N points with distinct x and y coordinates, output the order produced by repeatedly picking the most clockwise remaining point from the current one.	Medium5	GeometrySorting+2	No attempts yet	1s	128 MB	Judgeable
Wooden SticksGiven n sticks with length and weight, order them to minimize the number of setup steps, where a setup is needed unless both length and weight are nondecreasing from the previous stick.	Medium5	SortingGreedy+1	No attempts yet	1s	128 MB	Judgeable
Flip and ShiftGiven a circular binary string, decide whether repeated flips (swap the two outer of three consecutive disks) can gather all 1s and all 0s into two contiguous blocks.	Medium5	MathGreedy+1	No attempts yet	1s	128 MB	Judgeable
TransportationChoose a subset of passenger orders so that no route segment exceeds capacity n, maximizing total revenue.	Medium5	BacktrackingBrute force	No attempts yet	1s	128 MB	Judgeable
JosephFor each k, find the smallest step size m in the Josephus circle that kills all k bad people before any of the k good people.	Medium5	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Repeated Permutation CipherGiven a permutation key and a repeat count k, apply the permutation to each padded message k times and print the result.	Medium5	ArrayImplementation+2	No attempts yet	1s	128 MB	Judgeable
Card Game CheaterEve knows Adam's card order and must permute her own cards to maximize the number of positions where her card beats his.	Medium5	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
InvestmentStarting capital grows over at most 40 years by rebuying a portfolio of bonds each year; maximize the final amount.	Medium5	Dynamic programmingGreedy	No attempts yet	1s	128 MB	Judgeable
GunmanEach window is a rectangle at a distinct depth; decide whether one straight ray fired from the X axis can pass through all of them.	Medium5	GeometryBinary search+2	No attempts yet	2s	128 MB	Judgeable
Alternative Scale of NotationGiven a base B and a non-negative decimal integer x, find the unique string of digits from 1 to B whose value under the shifted base-B map equals x.	Medium5	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
DivisibilityGiven a sequence and a modulus K, decide whether some choice of + or - before each later element makes the total divisible by K.	Medium5	Dynamic programmingMath+2	No attempts yet	1s	128 MB	Judgeable
HighwaysConnect all towns with the cheapest new highways, where some links already exist, and report the summed squared lengths of the added edges.	Medium5	Minimum spanning treeUnion-find	No attempts yet	1s	128 MB	Judgeable
False CoinGiven recorded balance weighings of N coins with exactly one false coin, output the coin number if the results identify it uniquely, otherwise 0.	Medium5	Brute forceImplementation+2	No attempts yet	1s	128 MB	Judgeable
Spell CheckerGiven a dictionary and query words, mark each query correct, or list dictionary words reachable by one deletion, replacement, or insertion.	Medium5	StringHash map+2	No attempts yet	1s	128 MB	Judgeable
Bin PackingPack items into identical bins holding at most two items each so that the number of bins is minimized.	Medium5	GreedyTwo pointers+2	No attempts yet	1s	128 MB	Judgeable
DancersRepeatedly pair the two closest unpaired dancers, breaking ties by smaller indices, and output all pairs sorted.	Medium5	SortingGeometry+2	No attempts yet	1s	128 MB	Judgeable
Playground HideoutGiven a directed graph with weighted edges and direct ground costs per node, find the index of the node with the largest shortest-path distance from ground, breaking ties by smallest index.	Medium5	Shortest pathGraph+2	No attempts yet	1s	128 MB	Judgeable
Olympic GamesGiven each event's date and start and end times in hhmm, find the maximum number of events a person can attend without overlap, moving freely between venues.	Medium5	GreedySorting+2	No attempts yet	2s	256 MB	Judgeable
Diophantus of AlexandriaGiven n, count the pairs (x, y) with x <= y satisfying 1/x + 1/y = 1/n.	Medium5	Number theoryMath+2	No attempts yet	1s	128 MB	Judgeable
RelocationSplit up to 10 furniture items between two cars with capacity limits so that every item gets moved in the fewest number of paired trips.	Medium5	Dynamic programmingBinary search+2	No attempts yet	1s	128 MB	Judgeable
Number TricksFor each query, count the trailing zeros of n! in base b by factoring b and finding the minimum over primes of each exponent's count in n!.	Medium5	Number theoryMath+2	No attempts yet	1s	128 MB	Judgeable
Dart ScoringSimulate 301 dart games throw by throw, tracking doubles to start scoring, busts, and doubles to finish.	Medium5	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
A Bug's LifeGiven pairs of interacting bugs, decide whether a two-gender assignment exists so that no pair shares a gender.	Medium5	Union-findGraph	No attempts yet	3s	256 MB	Judgeable
Heavy TransportationFind the maximum weight that can travel from crossing 1 to crossing n, defined as the path whose smallest street limit is as large as possible.	Medium5	GraphMinimum spanning tree+2	No attempts yet	1s	128 MB	Judgeable
Magic TrickFor each of three paragraphs, follow the rule of jumping forward by the current word's length; list all distinct outcomes in the third paragraph, or -outside- if a jump overruns the text.	Medium5	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
Formula RacingSimulate cars on a grid track, applying per-turn commands and reporting final or crash states plus every start-line cell crossed, in order.	Medium5	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
CocktailsSimulate Angelo's cocktail mixing rules, track each cocktail's counts, and print the top ten by count then recipe-book order with computed prices.	Medium5	SimulationHash map+2	No attempts yet	1s	128 MB	Judgeable
Ship JourneyFind the latest whole-minute departure so the ship reaches 100 km strictly before the deadline, minimizing travel time.	Medium5	SimulationBrute force+1	No attempts yet	1s	128 MB	Judgeable
TomatoesGiven a 3D grid of ripe, unripe, and empty cells, find the minimum days for all tomatoes to ripen via 6-directional spread, or -1 if impossible.	Medium5	BFSGraph+1	No attempts yet	1s	256 MB	Judgeable
Catching FishGiven up to 100 fish on a large grid and a fixed net perimeter, find the placement of the net that covers the most fish.	Medium5	Brute forcePrefix sum+1	No attempts yet	1s	256 MB	Judgeable
FactoryGiven two orderings of the same N numbers, count pairs of connecting cables that cross when drawn as straight lines.	Medium5	SortingPrefix sum+1	No attempts yet	1s	256 MB	Judgeable
Balanced ChangeGiven counts of five coin types in a drawer and an amount, choose coins to give out so that the imbalance of the remaining coins is minimized.	Medium5	Dynamic programmingBrute force+1	No attempts yet	1s	128 MB	Judgeable
Reconstructing Binary TreesGiven the pre-order and in-order traversals of a binary tree with distinct labels, print its post-order traversal or report that no tree matches.	Medium5	TreeRecursion+2	No attempts yet	1s	128 MB	Judgeable
Traffic EngineeringGiven a directed network of named hosts where nodes cost 0 or 1 depending on ownership, report the cheapest route cost between each source-destination pair.	Medium5	GraphShortest path+2	No attempts yet	1s	256 MB	Judgeable
Paying the Dinner BillGiven each person's bill share and coin/bill counts across ten denominations, decide whether pooling all cash can pay the total exactly.	Medium5	GreedyMath+1	No attempts yet	2s	256 MB	Judgeable
Betting SetsPartition an N by M table of probabilities into groups of one cell per column to maximize the expected number of all-heads groups.	Medium5	Dynamic programmingBit manipulation+2	No attempts yet	1s	128 MB	Judgeable
Apocalyptic AlignmentGiven two A/B strings of equal length, find the minimum number of operations that repaint a contiguous segment with one fruit type to turn the first string into the second.	Medium5	Dynamic programmingGreedy+1	No attempts yet	1s	128 MB	Judgeable
Dual Priority QueueProcess a sequence of insert and min/max delete operations on a dual priority queue, then report the remaining max and min.	Medium5	HeapImplementation	No attempts yet	6s	256 MB	Judgeable
GoFlood-fill the empty regions of a Go board over multiple test cases, count each region for black or white by the colors of its neighboring stones, and report the winner by the score difference.	Medium5	GraphBFS+2	No attempts yet	1s	128 MB	Judgeable
Game DiceGiven up to 13 dice with various face counts and a target total, compute the probability of rolling exactly that sum, to five decimals.	Medium5	Dynamic programmingProbability+1	No attempts yet	1s	128 MB	Judgeable
Saruman's ArmyPlace the fewest palantirs on troop positions so every troop lies within range R of one.	Medium5	GreedySorting+1	No attempts yet	1s	128 MB	Judgeable
FootballGiven pairwise win probabilities, find the team most likely to win a fixed single-elimination bracket of 2^n teams.	Medium5	Dynamic programmingProbability+1	No attempts yet	1s	128 MB	Judgeable
Tic-Tac-ToeGiven a final tic-tac-toe board, decide whether it could result from a legal game played by the rules.	Medium5	ImplementationSimulation	No attempts yet	1s	128 MB	Judgeable
NimGiven a Nim position, count how many single-pile moves lead to a losing position (XOR of the remaining piles equals zero).	Medium5	Game theoryBit manipulation+1	No attempts yet	1s	128 MB	Judgeable
Polling StationsGiven an undirected graph, find the smallest set of vertices such that every edge touches at least one chosen vertex.	Medium5	GraphGreedy	No attempts yet	1s	64 MB	Judgeable
RailwayGiven a weighted tree, compute the total weight of the unique path between each queried pair of cities.	Medium5	TreePrefix sum+1	No attempts yet	1s	32 MB	Judgeable
Three Bit ComputerGiven a string over {a,b,c}, decide whether an all-uninitialized memory can be initialized to exactly that string with the two given operations.	Medium5	Dynamic programmingGreedy	No attempts yet	1s	32 MB	Judgeable
Deepest StationGiven a surface point (x, y) and depth d, decide whether a single 45-degree staircase reaches (0,0,d), it is impossible, or print the shallowest intermediate lobby.	Medium5	GeometryMath+1	No attempts yet	1s	128 MB	Judgeable
OutletsGiven power strips that swap between standard A and B outlets, find the maximum number of standard-A outlets that can end up powering computers.	Medium5	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
Digit Sum Over a RangeGiven l and u up to 2e9, find the total of the digit sums of every integer in that inclusive range.	Medium5	MathDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
Avoiding Financial NightmareGiven a loan principal, a term in months, and a monthly interest rate, find the fixed monthly payment so the balance hits zero at term end.	Medium5	Binary searchSimulation+2	No attempts yet	1s	128 MB	Judgeable
No Pause TelegraphGiven a string of dots and dashes and seven fixed letter codes, split it into codewords that minimize the resulting message alphabetically, or report that no split exists.	Medium5	Dynamic programmingString+2	No attempts yet	1s	128 MB	Judgeable
Arm Wrestling TournamentSimulate a single-elimination arm wrestling bracket of 2^N players where winners lose strength and recover K before each match; report the champion and the opponents beaten.	Medium5	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Romantic DateGiven Wibowo's 26 cards, find the maximum number of rounds he can win by pairing his cards against his opponent's 26 cards in the best order.	Medium5	GreedySorting+1	No attempts yet	1s	128 MB	Judgeable
Random GapGiven a linear congruential generator, find the largest gap between neighboring distinct values the sequence produces.	Medium5	SimulationHash map+2	No attempts yet	4s	128 MB	Judgeable
Nearest number - 2Replace each zero with the nearest nonzero value using Manhattan distance, but leave zeros that are tied between two or more nearest values unchanged.	Medium5	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
Network SaboteurSplit N nodes (N <= 20) into two sets A and B so the total weight of edges crossing between them is maximized.	Medium5	Brute forceBacktracking+1	No attempts yet	1s	128 MB	Judgeable
Binary WitchGiven a binary string, predict the next L digits by matching suffixes of length 13 down to 1 against earlier occurrences, using the rightmost match.	Medium5	StringString matching+2	No attempts yet	1s	128 MB	Judgeable
DecisionCount connected dark regions on a grid where each cell is a diagonal half or a full square, connecting only through shared cell edges.	Medium5	GraphDFS+2	No attempts yet	1s	512 MB	Judgeable
SkyscrapersFor each queried day, count maximal blocks of adjacent skyscrapers whose heights exceed the rising sea level.	Medium5	SortingArray+1	No attempts yet	2s	128 MB	Judgeable
PearlsGiven demand and price per pearl for classes in increasing quality order, find the cheapest way to buy all pearls when each class's order may be upgraded to a higher class, paying 10 extra pearls' worth per purchase.	Medium5	Dynamic programmingPrefix sum+1	No attempts yet	1s	128 MB	Judgeable
Tiling VerificationGiven a floor and up to 100 rectangles, decide whether they overlap, stick out of the floor, or fail to cover it, printing which condition fails first.	Medium5	GeometryImplementation+2	No attempts yet	1s	128 MB	Judgeable
Afternoon TeaTrack the tea and milk levels in a cup over a sequence of half drinks and refills, and report which ingredient was consumed more.	Medium5	Dynamic programmingMath+1	No attempts yet	3s	32 MB	Judgeable
Sunny IslandAssign product sets of given minimum sizes to stalls on a ring, non-crossing bridges, and rays so neighbours share nothing, minimizing the product count.	Medium5	GreedyGraph+1	No attempts yet	1s	128 MB	Judgeable
GrandparentsFind the grandmother's age from a puzzle relation and print an extra string on every X-th test line.	Medium5	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Cookie MonsterGiven N and the decimal digits of N! with two adjacent digits replaced by 'ab', find the two missing digits.	Medium5	Number theoryMath+1	No attempts yet	1s	128 MB	Judgeable
Reversing a Snake on a Complete GraphGiven a snake path on a complete graph, decide whether the head and tail can be swapped by a sequence of legal moves.	Medium5	GraphGreedy+1	No attempts yet	1s	128 MB	Judgeable
The Very Dirty ChainFor each circular string, output the lexicographically smallest rotation, without reversing the chain.	Medium5	StringTwo pointers	No attempts yet	1s	128 MB	Judgeable
Chess Player's DayGiven a tournament's transitive closure, find three players with no deduced comparison among any pair, choosing the lexicographically smallest triple.	Medium5	GraphGreedy+1	No attempts yet	2s	128 MB	Judgeable
The History of CottonGiven n, m, and g, print the g-th m-element subset of {1,...,n} in lexicographic order.	Medium5	CombinatoricsMath+1	No attempts yet	1s	128 MB	Judgeable