Problems

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Total results29,417 problems

Memory
Medium6
Game theory, Math+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Taekwondo King
Medium6
Dynamic programming, Greedy+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Marbles on the tree
Medium6
Tree, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hourglass
Medium6
Graph, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
After-Party Drink Cap
Medium6
Greedy, Binary search+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Younghoon's Coloring Book
Medium6
Combinatorics, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
KUBC League (Small)
Medium6
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Tiling the Shower Floor (Large)
Medium6
Divide and conquer, Recursion+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Salt and Pepper (Large)
Medium6
Sliding window, Sorting+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Matching the Integral with a Riemann Sum
Medium6
Math, Binary search+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
A Good Contest
Medium6
Greedy, Brute force+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Defend the CTP!!!
Medium6
Graph, DFS+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Island Trip
Medium6
Graph, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Number Tiles
Medium6
Brute force, Greedy+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Transforming Robot
Medium6
Graph, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mission Improbable
Medium6
Greedy, Array+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Posterize
Medium6
Dynamic programming, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Scenery
Medium6
Greedy, Sorting+2
No attempts yet
Time limit
6s
Memory limit
512 MB
Judgeable
A rain of shooting stars
Medium6
Array, Sorting+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Crush Fever
Medium6
DFS, Brute force+2
No attempts yet
Time limit
1.5s
Memory limit
512 MB
Judgeable
Sickly Yunho
Medium6
Dynamic programming, Array+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Yeongwoo and God4
Medium6
Simulation, Math+2
No attempts yet
Time limit
1.5s
Memory limit
512 MB
Judgeable
The Longest Fence
Medium6
Array, Two pointers+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Tile Flipping (Easy)
Medium6
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Brave Warrior Jinsu
Medium6
Sorting, Binary search+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Ant Nest
Medium6
Trie, Tree+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cutting the puzzle
Medium6
Stack, Array
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Impossible Design
Medium6
Geometry, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Kimi No Ichi Wa.
Medium6
Graph, Math
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Closest Pair
Medium6
Sorting, Two pointers+1
No attempts yet
Time limit
1.5s
Memory limit
512 MB
Judgeable
Flow Graph Complexity
Medium6
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Dueling Philosophers
Medium6
Graph, Topological sort+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Bumper to bumper traffic
Medium6
Implementation, Simulation+2
No attempts yet
Time limit
4s
Memory limit
512 MB
Judgeable
Bot or not
Medium6
Implementation, Hash map+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Nothing But The Truth
Medium6
String, Intervals+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
The County Fair
Medium6
Dynamic programming, Graph+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
The Climbing Wall
Medium6
Graph, BFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Bedtime Reading II
Medium6
Number theory, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Cows on a Leash
Medium6
Greedy, Intervals+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Fashion Show
Medium6
Graph, Two pointers+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Alphabet Cake (Small)
Medium6
Greedy, Implementation+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Ratatouille (Large)
Medium6
Greedy, Two pointers+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Play the Dragon (Small)
Medium6
Brute force, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Horse Cruise Control
Medium6
Math, Greedy+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Ample Syrup (Large)
Medium6
Greedy, Sorting+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Fresh Chocolate (Small)
Medium6
Greedy, Math+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Roller Coaster Scheduling (Large)
Medium6
Greedy, Sorting+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Googlements (Small)
Medium6
Graph, Simulation+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Googlements (Large)
Medium6
Graph, DFS+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Good News and Bad News (Small)
Medium6
Graph, Greedy+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Dice Straight (Small)
Medium6
Greedy, Hash map+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Integer Game
Medium6
Math, Number theory+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Dumpling shop owner Seungwon Park
Medium6
Dynamic programming, Greedy+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Two Water Jugs
Medium6
BFS, Graph+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Cats
Medium6
Greedy, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
16 MB
Judgeable
Subarray XOR sums
Medium6
Prefix sum, Bit manipulation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Tae and Dotori split a chocolate bar
Medium6
Backtracking, DFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Inserting operators
Medium6
Brute force, Backtracking+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Start and Link
Medium6
Brute force, Backtracking+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Sum of four primes
Medium6
Number theory, Brute force+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Minimum subarray average
Medium6
Array, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Beads
Medium6
Sorting, Simulation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Mensa Safe
Medium6
Graph, Simulation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Elevator Prank
Medium6
Bit manipulation, Brute force+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Turning Off the Lights
Medium6
Brute force, Bit manipulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Good delivery clerk
Medium6
Math, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Playing with Fire
Medium6
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Game Map
Medium6
Graph, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Philosopher's Walk
Medium6
Divide and conquer, Recursion+2
No attempts yet
Time limit
0.5s
Memory limit
512 MB
Judgeable
Counting Tetris Figures
Medium6
Implementation, Graph+2
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
A Garden with Ponds
Medium6
Brute force, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Go around the Labyrinth
Medium6
Graph, DFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Pond Cascade
Medium6
Simulation, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Punching Power
Medium6
Graph, Greedy+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Abandoned Animal
Medium6
Greedy, Array+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Disastrous Doubling
Medium6
Simulation, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Lemonade Trade
Medium6
Dynamic programming, Hash map+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Galactic Collegiate Programming Contest
Medium6
Sorting, Binary search+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Import Spaghetti
Medium6
Graph, BFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Cued In
Medium6
Greedy, Implementation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Stationary bike programs
Medium6
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hipercampo
Medium6
Geometry, Sorting+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lost in Translation
Medium6
Graph, BFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Red Rover
Medium6
Dynamic programming, String
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Vin Diagrams
Medium6
Graph, BFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
A Question of Ingestion
Medium6
Dynamic programming, Greedy+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Honey Heist
Medium6
Graph, BFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Orderly Class
Medium6
String, Two pointers+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Faulty Robot
Medium6
Graph, DFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Straight Shot
Medium6
Math, Binary search+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Ducks in a Row
Medium6
Dynamic programming, Greedy+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Jumping Haybales
Medium6
BFS, Dynamic programming+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Move Away
Medium6
Geometry, Binary search
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Kotlin Island
Medium6
Greedy, Implementation+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Little Difference
Medium6
Number theory, Math+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Dangerous Discus
Medium6
Dynamic programming, Sliding window+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Loading Cargo
Medium6
Graph, DFS+2
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Intuidiff II
Medium6
Dynamic programming, Intervals+2
No attempts yet
Time limit
4s
Memory limit
512 MB
Judgeable
Just Terraffic!
Medium6
Dynamic programming, Greedy
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Domino Killing
Medium6
Simulation, Hash map+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
MemoryGiven R times C face-down cards forming pairs, find the best-case and worst-case number of actions a perfect-memory player needs to clear the board.	Medium6	Game theoryMath+2	No attempts yet	1s	256 MB	Judgeable
Taekwondo KingWith S < T, using combo A doubles S but adds 3 to T, and combo B adds 1 to S. Find the fewest kicks that make S equal T.	Medium6	Dynamic programmingGreedy+2	No attempts yet	2s	128 MB	Judgeable
Marbles on the treeGiven a rooted ordered binary tree, find the leaf where the K-th marble stops, where each marble at a two-child node goes to the left if left subtree has at most the right subtree's resting marbles, else right.	Medium6	TreeDFS+2	No attempts yet	1s	128 MB	Judgeable
HourglassCount subgraphs formed by two triangles that share exactly one vertex, in an undirected graph with up to 200 vertices.	Medium6	GraphCombinatorics+2	No attempts yet	1s	128 MB	Judgeable
After-Party Drink CapFind the smallest cap S such that each person i gets an integer amount in [L_i, min(R_i, S)] and the amounts sum exactly to T.	Medium6	GreedyBinary search+2	No attempts yet	1s	128 MB	Judgeable
Younghoon's Coloring BookCount the ways to place one red and one blue cell in each row and column of an N x N grid, with no cell both colors, modulo 1e9+7.	Medium6	CombinatoricsMath+1	No attempts yet	1s	128 MB	Judgeable
KUBC League (Small)Given a tournament on N players, find the longest simple path starting at player 1 and output the lexicographically smallest such path.	Medium6	GraphDFS+2	No attempts yet	1s	256 MB	Judgeable
Tiling the Shower Floor (Large)Fill a 2^K by 2^K grid with L shaped trominoes leaving one drain cell empty, using the specified recursive placement and numbering scheme.	Medium6	Divide and conquerRecursion+2	No attempts yet	1s	512 MB	Judgeable
Salt and Pepper (Large)For each W by W window in the matrix, output the median of its W^2 pixel values.	Medium6	Sliding windowSorting+1	No attempts yet	1s	512 MB	Judgeable
Matching the Integral with a Riemann SumGiven a polynomial, an interval [a,b], and N subintervals, find epsilon in [0, dx] where the Riemann sum equals the exact integral, or print -1.	Medium6	MathBinary search+2	No attempts yet	1s	512 MB	Judgeable
A Good ContestGiven a partially hidden scoreboard with known solve counts and a staircase visibility pattern, decide whether the hidden entries can be filled so every contestant solves at least one problem, every problem is solved, and nobody solves all problems.	Medium6	GreedyBrute force+2	No attempts yet	1s	512 MB	Judgeable
Defend the CTP!!!Given a directed graph and many queries C, decide for each C whether 1 can reach C and C can reach N.	Medium6	GraphDFS+2	No attempts yet	2s	256 MB	Judgeable
Island TripGiven an undirected graph with node heights, for each query (A, K) find the minimum height reachable from A in exactly K edge steps, or -1 if impossible.	Medium6	GraphDynamic programming+2	No attempts yet	1s	256 MB	Judgeable
Number TilesFind the digit-distinct number (no repeated digit) closest to N, breaking ties toward the smaller value.	Medium6	Brute forceGreedy+2	No attempts yet	1s	256 MB	Judgeable
Transforming RobotGiven N digit strings of equal length, move between states with cost equal to the sum of squared digit differences per position, and find the minimum cost from a start state to a target state.	Medium6	GraphShortest path+2	No attempts yet	1s	128 MB	Judgeable
Mission ImprobableGiven a grid of pile heights, find the maximum number of crates that can be removed while keeping every row maximum, column maximum, and empty/non-empty pattern unchanged.	Medium6	GreedyArray+2	No attempts yet	1s	512 MB	Judgeable
PosterizeChoose k allowed red values so the weighted sum of squared distances from the d distinct intensities is minimized.	Medium6	Dynamic programmingMath+2	No attempts yet	2s	512 MB	Judgeable
SceneryGiven n time windows and a fixed photo duration t, decide whether all photos can be scheduled as non-overlapping intervals.	Medium6	GreedySorting+2	No attempts yet	6s	512 MB	Judgeable
A rain of shooting starsPlace an axis-aligned square of side L to cover as many of K points as possible, counting points on any edge as covered.	Medium6	ArraySorting+2	No attempts yet	2s	256 MB	Judgeable
Crush FeverOn an N by M grid of 5 piece kinds, choose 3 taps; each tap clears the connected same-kind group of the tapped cell and scores size squared, with pieces falling down after each tap. Maximize total points.	Medium6	DFSBrute force+2	No attempts yet	1.5s	512 MB	Judgeable
Sickly YunhoGiven a string of B, L, D doses, remove from either end in the fixed order B, L, D, B, L, D... and find the most doses removable before the required dose is missing from both ends.	Medium6	Dynamic programmingArray+2	No attempts yet	1s	512 MB	Judgeable
Yeongwoo and God4Given a character and a sequence of monsters generated by recurrence, decide whether the character survives all N fights in order and print the final stats or -1.	Medium6	SimulationMath+2	No attempts yet	1.5s	512 MB	Judgeable
The Longest FenceGiven up to 10^6 board lengths (each at most 2000), pair them into boards of equal sum and report the largest possible number of boards plus how many sums reach it.	Medium6	ArrayTwo pointers+2	No attempts yet	2s	512 MB	Judgeable
Tile Flipping (Easy)Given the first row of an N by N black/white board, fill the remaining rows so that flipping every black tile once (which also flips its orthogonal neighbors) turns the whole board white.	Medium6	ImplementationSimulation+2	No attempts yet	1s	512 MB	Judgeable
Brave Warrior JinsuGiven N enemy stat triples and a target K, find the minimum total stat points so Jinsu's strength, agility, and intelligence let him dominate at least K enemies.	Medium6	SortingBinary search+2	No attempts yet	1s	256 MB	Judgeable
Ant NestGiven paths of food names from the top floor down, print the merged tree with each node indented by two dashes per depth and children in dictionary order.	Medium6	TrieTree+2	No attempts yet	1s	256 MB	Judgeable
Cutting the puzzleGiven the heights of a histogram, find the area of the largest axis-aligned rectangle contained in it.	Medium6	StackArray	No attempts yet	2s	256 MB	Judgeable
Impossible DesignGiven the circle order of a permutation of 0 to N-1, decide whether chords drawn between every pair at height x+y ever intersect.	Medium6	GeometryCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
Kimi No Ichi Wa.Given a special one-way line where every non-endpoint station balances in and out degree, find the meeting station closest to the start.	Medium6	GraphMath	No attempts yet	2s	256 MB	Judgeable
Closest PairBoth point sets lie on horizontal lines; find the Manhattan distance of the closest P-Q pair and count how many distinct pairs achieve it.	Medium6	SortingTwo pointers+1	No attempts yet	1.5s	512 MB	Judgeable
Flow Graph ComplexityParse a comma-separated flow-graph string of S, B(...), L(...) nodes, count forward and backward edges and nodes, and print \|EF\| + W*\|EB\| - \|V\| + 2 or -1 if malformed.	Medium6	StringImplementation+2	No attempts yet	1s	512 MB	Judgeable
Dueling PhilosophersGiven directed edges meaning essay d must precede essay u, decide whether the ordering is impossible, unique, or has multiple solutions.	Medium6	GraphTopological sort+2	No attempts yet	2s	512 MB	Judgeable
Bumper to bumper trafficTwo cars 4.4 m long start stopped on a line and alternate between stopping and driving at 1 m/s at given times; decide whether they ever touch, giving the first contact second rounded up.	Medium6	ImplementationSimulation+2	No attempts yet	4s	512 MB	Judgeable
Bot or notScore pairs of secondary accounts by shared posts they follow, then count accounts similar to a known human.	Medium6	ImplementationHash map+1	No attempts yet	2s	512 MB	Judgeable
Nothing But The TruthGiven facts about which person was at which place and when, count how many claims in a text (who met whom, who was where) are definitely false.	Medium6	StringIntervals+1	No attempts yet	2s	512 MB	Judgeable
The County FairFarmer John visits booths with fixed giveaway times and directed travel times, choosing a route that collects the most prizes.	Medium6	Dynamic programmingGraph+1	No attempts yet	2s	512 MB	Judgeable
The Climbing WallGiven holds on a wall, find the fewest holds Bessie must step on to climb from within 1000 mm of the ground to within 1000 mm of the top, moving only between holds at most 1000 mm apart.	Medium6	GraphBFS+2	No attempts yet	2s	512 MB	Judgeable
Bedtime Reading IIFind all aliquot (bess) cycles starting in [start,end] whose first element is the chain minimum, skipping any chain where a value exceeds 2,000,000.	Medium6	Number theoryImplementation+2	No attempts yet	2s	512 MB	Judgeable
Cows on a LeashGiven N intervals, find the fewest half-integer cut points so that every interval contains at least one chosen point.	Medium6	GreedyIntervals+1	No attempts yet	2s	512 MB	Judgeable
Fashion ShowGiven a legal partial placement of +, x, and o models on an N by N grid, add or upgrade models to maximize style points under the row/column and diagonal rules.	Medium6	GraphTwo pointers+2	No attempts yet	5s	512 MB	Judgeable
Alphabet Cake (Small)Assign every blank cell of a small grid to an existing letter so each letter occupies one rectangle, choosing the lexicographically smallest result.	Medium6	GreedyImplementation+2	No attempts yet	5s	512 MB	Judgeable
Ratatouille (Large)Given amounts of each ingredient, pair packages into kits so that each package in a kit is within 90 to 110 percent of the recipe amount for the kit's integer serving count, maximizing kits.	Medium6	GreedyTwo pointers+1	No attempts yet	5s	512 MB	Judgeable
Play the Dragon (Small)Given health and attack stats for a dragon and a knight, plus buff and debuff amounts, find the fewest turns to defeat the knight or report it impossible.	Medium6	Brute forceSimulation+1	No attempts yet	5s	512 MB	Judgeable
Horse Cruise ControlFind the largest constant speed Annie can ride without passing any horse that slows as it catches leaders, expressed as a reduced fraction.	Medium6	MathGreedy+2	No attempts yet	5s	512 MB	Judgeable
Ample Syrup (Large)Choose K of N cylindrical pancakes and stack them largest radius first to maximize exposed surface area, reported as a multiple of pi.	Medium6	GreedySorting+2	No attempts yet	5s	512 MB	Judgeable
Fresh Chocolate (Small)Choose the order of groups so that as many as possible receive only chocolate from freshly opened packs, given that leftovers must be finished first.	Medium6	GreedyMath+2	No attempts yet	5s	512 MB	Judgeable
Roller Coaster Scheduling (Large)Given tickets each binding a customer to a seat, find the minimum rides and the minimum promotions so every ticket is honored once per ride.	Medium6	GreedySorting+2	No attempts yet	5s	512 MB	Judgeable
Googlements (Small)Given a googlement G that may have already decayed, count all length-L digit strings that reach G after zero or more decay steps.	Medium6	GraphSimulation+2	No attempts yet	5s	512 MB	Judgeable
Googlements (Large)Count how many googlement strings could have decayed, through zero or more steps, into a given observed googlement.	Medium6	GraphDFS+2	No attempts yet	5s	512 MB	Judgeable
Good News and Bad News (Small)Assign a nonzero integer in [-F^2, F^2] to each directed edge so every vertex's outgoing sum equals its incoming sum, choosing the lexicographically smallest solution.	Medium6	GraphGreedy+2	No attempts yet	5s	512 MB	Judgeable
Dice Straight (Small)Given N dice with six distinct faces each, find the longest run of consecutive integers you can place on top using each die at most once.	Medium6	GreedyHash map+1	No attempts yet	5s	512 MB	Judgeable
Integer GameGiven N and up to 15 divisors, remove multiples of each in order and count how many numbers from 1 to N survive.	Medium6	MathNumber theory+2	No attempts yet	2s	512 MB	Judgeable
Dumpling shop owner Seungwon ParkMake at most limited numbers of m filler dumplings and unlimited filler-free ones from n grams of flour to maximize sales.	Medium6	Dynamic programmingGreedy+1	No attempts yet	2s	512 MB	Judgeable
Two Water JugsGiven two jug capacities and a target pair of water amounts, find the minimum fills, empties, and pours from (0,0) or report -1.	Medium6	BFSGraph+2	No attempts yet	2s	512 MB	Judgeable
CatsFind the minimum number of moves to reorder a line of cats, dogs, and lions so no cat is adjacent to a dog.	Medium6	GreedyDynamic programming+2	No attempts yet	1s	16 MB	Judgeable
Subarray XOR sumsFor a sequence, count how often each XOR value appears among all contiguous subarrays, then report the most frequent value, breaking ties by choosing the smallest.	Medium6	Prefix sumBit manipulation+2	No attempts yet	2s	512 MB	Judgeable
Tae and Dotori split a chocolate barCount assignments of U cells to T or D so each person's region is connected, the sizes differ by at most K, and neither region contains a 2x2 block.	Medium6	BacktrackingDFS+2	No attempts yet	2s	512 MB	Judgeable
Inserting operatorsGiven up to 11 numbers and counts of the four arithmetic operators, place the operators between adjacent numbers, evaluate left to right without precedence, and report the maximum and minimum results.	Medium6	Brute forceBacktracking+2	No attempts yet	2s	512 MB	Judgeable
Start and LinkSplit N people into two equal teams to minimize the difference between the teams' total pairwise ability sums.	Medium6	Brute forceBacktracking+1	No attempts yet	2s	512 MB	Judgeable
Sum of four primesFor each n, print the lexicographically smallest non-decreasing quadruple of primes summing to n, or Impossible.	Medium6	Number theoryBrute force+1	No attempts yet	2s	512 MB	Judgeable
Minimum subarray averageFind the starting index of a length-two-or-more subarray whose average is smallest, breaking ties by smallest start.	Medium6	ArrayMath+1	No attempts yet	1s	512 MB	Judgeable
BeadsBeads of equal mass collide elastically on a line; find the position of the one marked red after t seconds.	Medium6	SortingSimulation+1	No attempts yet	2s	512 MB	Judgeable
Mensa SafeEach grid cell points to another cell; find the start that visits all N*N cells exactly once before repeating, or report none or many.	Medium6	GraphSimulation+2	No attempts yet	2s	512 MB	Judgeable
Elevator PrankEach move toggles a fixed set of buttons and costs N, N/2, N/2, or N/3 seconds; count the distinct button states reachable with total time at most m, including pressing nothing.	Medium6	Bit manipulationBrute force+2	No attempts yet	1s	512 MB	Judgeable
Turning Off the LightsGiven a 10x10 grid of lit and unlit bulbs, find the minimum presses so that every bulb ends up off.	Medium6	Brute forceBit manipulation+2	No attempts yet	1s	128 MB	Judgeable
Good delivery clerkFor each offered extra road between two houses, compute the shortest walk from house 0 that visits every house and traverses the new road fully, then print the minimum over all offers.	Medium6	MathGreedy+2	No attempts yet	1s	128 MB	Judgeable
Playing with FireTwo distinct people start just above the burning top tile and each step down or diagonally, never landing on the same tile; count escape sequences.	Medium6	Dynamic programmingCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
Game MapGiven an undirected connected graph, find the longest simple path where the degree of each successive vertex strictly increases.	Medium6	GraphDynamic programming+2	No attempts yet	1s	512 MB	Judgeable
Philosopher's WalkGiven the step index m along a Hilbert curve of side n = 2^k, find the cell coordinates (x, y) of that step.	Medium6	Divide and conquerRecursion+2	No attempts yet	0.5s	512 MB	Judgeable
Counting Tetris FiguresCount occurrences of each of five tetromino shapes (rotations allowed, no flips) in a grid colored so adjacent figures differ.	Medium6	ImplementationGraph+2	No attempts yet	1s	64 MB	Judgeable
A Garden with PondsGiven a small elevation grid, find the rectangular pond whose border cells all exceed its interior cells, maximizing the total water it can hold.	Medium6	Brute forceImplementation+2	No attempts yet	2s	512 MB	Judgeable
Go around the LabyrinthDecide whether a walk from the top-left corner can visit the other three corners and come back, where each non-entrance room collapses after one visit.	Medium6	GraphDFS+2	No attempts yet	2s	512 MB	Judgeable
Pond CascadeGiven pond capacities and a common fill rate, compute the exact times when the lowest pond begins to overflow and when every pond is full.	Medium6	SimulationMath+1	No attempts yet	2s	512 MB	Judgeable
Punching PowerChoose the largest subset of given grid points so every pair is more than 1.3 meters apart.	Medium6	GraphGreedy+2	No attempts yet	2s	512 MB	Judgeable
Abandoned AnimalGiven each store's stock and the ordered list of purchases, count how many store assignments make store numbers nondecreasing: zero, one, or many.	Medium6	GreedyArray+1	No attempts yet	2s	512 MB	Judgeable
Disastrous DoublingEach hour the bacteria double, then an experiment consumes b_i; report the remainder modulo 1e9+7 or error if supply runs short.	Medium6	SimulationMath+2	No attempts yet	2s	512 MB	Judgeable
Lemonade TradeGiven a sequence of one-way lemonade exchanges walked in order, find the maximum litres of blue obtainable starting from one litre of pink, capped at 10.	Medium6	Dynamic programmingHash map+1	No attempts yet	2s	512 MB	Judgeable
Galactic Collegiate Programming ContestAfter each of m solve events, report the rank of team 1 among n teams ranked by solve count and then penalty.	Medium6	SortingBinary search+2	No attempts yet	5s	512 MB	Judgeable
Import SpaghettiFind a shortest cycle in a directed dependency graph and print it in lexicographically smallest rotation order, or report that none exists.	Medium6	GraphBFS+2	No attempts yet	2s	512 MB	Judgeable
Cued InGiven the balls left on a snooker table, compute the maximum points a player can score in one run following the red-colour alternation rules.	Medium6	GreedyImplementation+2	No attempts yet	1s	512 MB	Judgeable
Stationary bike programsCount sequences of T levels where each step changes by exactly 1 and all values stay between M and N, modulo 1e9+7.	Medium6	Dynamic programming	No attempts yet	1s	1024 MB	Judgeable
HipercampoGiven two anchors on the x-axis and N points above, choose the largest subset whose segments to both anchors meet only at the anchors.	Medium6	GeometrySorting+2	No attempts yet	1s	1024 MB	Judgeable
Lost in TranslationGiven translators as weighted undirected edges, choose a set minimizing each target language's hop distance from English first, then total fee.	Medium6	GraphBFS+2	No attempts yet	2s	512 MB	Judgeable
Red RoverGiven a route string over N, S, E, W of length at most 100, find the minimum total length of a message using one optional macro M and its definition that expands to the route.	Medium6	Dynamic programmingString	No attempts yet	2s	512 MB	Judgeable
Vin DiagramsGiven a grid with two non-crossing loop outlines for sets A and B, count the periods strictly inside A only, B only, and their overlap.	Medium6	GraphBFS+2	No attempts yet	2s	512 MB	Judgeable
A Question of IngestionGiven n hourly courses with calorie counts, maximize total calories eaten when the per-hour limit starts at m, shrinks to two thirds while eating, and resets after two skipped hours.	Medium6	Dynamic programmingGreedy+2	No attempts yet	2s	512 MB	Judgeable
Honey HeistBuild the adjacency of a hexagonal honeycomb of side R, remove wax cells, and find the shortest number of chewed cells from A to B, checking it against N.	Medium6	GraphBFS+2	No attempts yet	2s	512 MB	Judgeable
Orderly ClassGiven two equal-length strings A and B, count the intervals in A such that reversing that interval turns A into B.	Medium6	StringTwo pointers+2	No attempts yet	2s	512 MB	Judgeable
Faulty RobotGiven a directed graph where at most one designated forced edge leaves each node, count the nodes where the robot can end up stopping if it breaks the forced rule at most once along the way.	Medium6	GraphDFS+2	No attempts yet	2s	512 MB	Judgeable
Straight ShotChoose a fixed heading so a robot crossing north-south moving sidewalks lands at (X,0); report the travel time or "Too hard" if it exceeds 2X/v.	Medium6	MathBinary search+1	No attempts yet	1s	512 MB	Judgeable
Ducks in a RowFind the fewest flips needed so the string contains at least k maximal runs of D of length at least n.	Medium6	Dynamic programmingGreedy+2	No attempts yet	2s	512 MB	Judgeable
Jumping HaybalesOn an n by n grid with haybale obstacles, find the fewest jumps of length 1 to k moving only east or south from the top-left corner to the bottom-right corner, or -1 if unreachable.	Medium6	BFSDynamic programming+2	No attempts yet	2s	512 MB	Judgeable
Move AwayFind the farthest point from the origin inside the intersection of n disks and print that distance rounded to three decimals.	Medium6	GeometryBinary search	No attempts yet	2s	512 MB	Judgeable
Kotlin IslandDig whole rows and columns of an h by w grid so the dry cells form exactly n connected components, printing the lexicographically smallest plan.	Medium6	GreedyImplementation+1	No attempts yet	3s	512 MB	Judgeable
Little DifferenceList all factorizations of n into factors that differ by at most 1, or report infinitely many.	Medium6	Number theoryMath+1	No attempts yet	3s	512 MB	Judgeable
Dangerous DiscusGiven falling acid drops in columns, decide whether the single-pixel disc can stay at some height and cross without ever touching a drop.	Medium6	Dynamic programmingSliding window+2	No attempts yet	2s	512 MB	Judgeable
Loading CargoDecide whether N capsules can be split between two compartments of capacities L and R so that no conflicting pair shares a compartment.	Medium6	GraphDFS+2	No attempts yet	3s	512 MB	Judgeable
Intuidiff IIGiven intervals in the order they appear in a modified document, choose a subsequence of intervals whose original ranges strictly increase; maximize total characters left plain.	Medium6	Dynamic programmingIntervals+2	No attempts yet	4s	512 MB	Judgeable
Just Terraffic!Given sorted trigger times, count cars with two axles and cars with three axles where gaps under 1000 ms join the same vehicle and gaps over 2000 ms split them.	Medium6	Dynamic programmingGreedy	No attempts yet	3s	512 MB	Judgeable
Domino KillingGiven up to 100000 dominoes on a grid with orientations, count how many topple after a push using the 90-degree blocking rule.	Medium6	SimulationHash map+2	No attempts yet	2s	512 MB	Judgeable