Problems

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Total results29,408 problems

Destroying the spire
Medium6
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Puang and the Staircase Sequence
Medium6
Dynamic programming, Array+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Puang and Coins
Medium6
Prefix sum, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
86 (Eighty-Six) 2
Medium6
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Puang and the Treadmill
Medium6
Math, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Alive or Dead?
Medium6
Simulation, Implementation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Puang and Level Up
Medium6
Binary search, Dynamic programming+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Toy Mixing
Medium6
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Choosing a Room
Medium6
Shortest path, Graph
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
SNUPTI
Medium6
Hash map, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Prime Calling Game
Medium6
Game theory, Number theory+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Melborp Lacissalc
Medium6
Dynamic programming, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Find the Parts
Medium6
Matrix, String matching+1
No attempts yet
Time limit
4s
Memory limit
2048 MB
Judgeable
One Dimensional
Medium6
Divide and conquer, Recursion+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
1 subtraction
Medium6
String, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Jump Showdown
Medium6
Combinatorics, Dynamic programming+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Building Bombing
Medium6
Dynamic programming, Greedy
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Connecting Cables
Medium6
Sorting, Prefix sum
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Grid
Medium6
Implementation, Geometry+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Computation - Task 4
Medium6
Implementation, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Computation - Task 6
Medium6
Implementation, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Good Segment Subsequence
Medium6
Dynamic programming, Segment tree
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Which Number
Medium6
Binary search, Number theory+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Pretty chocolate and number game
Medium6
Dynamic programming, Recursion
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Chocolate and the King Game
Medium6
Dynamic programming, Graph
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Food Poisoning
Medium6
Math, Combinatorics
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
K-gap Subsequence
Medium6
Dynamic programming, Segment tree+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fast Random Message Relay
Medium6
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Bad Tree
Medium6
Combinatorics, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sum of a Function
Medium6
Number theory, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Median Inversion String
Medium6
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cooperative Escape
Medium6
Graph, Shortest path
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Mountain View
Medium6
Sliding window, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Alex is Right
Medium6
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Videogame Probability
Medium6
Dynamic programming, Probability
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Multiples
Medium6
Number theory, Combinatorics+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Bouncing Bunnies
Medium6
BFS, Hash map+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Acquainted Through Friends
Medium6
Number theory, Greedy+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Squaring the Triangle
Medium6
Math, Combinatorics+2
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Course Selection
Medium6
Graph, BFS
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Rain Gauge
Medium6
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Jar Game
Medium6
Game theory, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Build a Staircase (Large)
Medium6
Dynamic programming, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Hansel and Gretel
Medium6
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Hyundai Mobis Air Suspension
Medium6
String matching, Trie
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Sum of Powers 1
Medium6
Math, Number theory
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Bubble-bubble Sort
Medium6
Array, Math
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Adjusted Average
Medium6
Sorting, Two pointers+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Grinding Gravel
Medium6
Bit manipulation, Dynamic programming
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
House Numbering
Medium6
Graph, Implementation
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Lowest Latency
Medium6
Divide and conquer, Sorting+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Codepowers
Medium6
Prefix sum, Sorting+1
No attempts yet
Time limit
1.234s
Memory limit
1024 MB
Judgeable
Breeding Bugs
Medium6
Graph, Number theory
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Diabolic Doofenshmirtz
Medium6
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Guessing Game
Medium6
Graph, Implementation
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Enigmatic Enumeration
Medium6
Graph, BFS
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Kapr2kar's r0utine
Medium6
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Array
Medium6
Math, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Mower
Medium6
Game theory, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Shamans
Medium6
Matrix, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sequence Sum 2
Medium6
Math, Number theory
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Match of the Millennium
Medium6
Sorting, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Gomgomi's Diet Management 2
Medium6
Graph, BFS
No attempts yet
Time limit
3.5s
Memory limit
1024 MB
Judgeable
Gomgomi's Last-Minute Cramming
Medium6
Tree, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fibonacci, the last sequence, and queries
Medium6
Segment tree, Math
No attempts yet
Time limit
1.2s
Memory limit
1024 MB
Judgeable
Shuffle Game
Medium6
Dynamic programming, String
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Light Placement
Medium6
BFS, Greedy+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Nonogram
Medium6
Dynamic programming, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Interplanetary Study Meeting
Medium6
Graph, Tree+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Fair Division
Medium6
Number theory, Math
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Where Am I?
Medium6
Simulation, Brute force+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
An Unbroken Heart 1
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
NATO Phonetic Alphabet and Queries
Medium6
Dynamic programming, Recursion+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Roha's Farming
Medium6
Dynamic programming, Graph+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Hanyang Gawang
Medium6
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Toward All Solve!
Medium6
Segment tree, Simulation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Arms of a Tree
Medium6
Tree, DFS+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Hexomino
Medium6
Brute force, Backtracking+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Going in Circles
Medium6
Implementation, Simulation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
High-quality Tree
Medium6
Tree, Dynamic programming
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Last Guess
Medium6
String, Matrix+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Constellations
Medium6
Greedy, Simulation+1
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Differences
Medium6
String, Brute force
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Insertions
Medium6
String matching, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sokoban
Medium6
Shortest path, BFS+1
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Displacing Particles
Medium6
Bit manipulation, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Numbers on Both Sides
Medium6
Sliding window, Heap+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Starflower Serenade (Hard)
Medium6
Dynamic programming, Probability+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Sled track in the winter forest
Medium6
Implementation, Matrix+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Restrooms
Medium6
Dynamic programming, Greedy+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Möbius
Medium6
Number theory, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Tree Plus 1
Medium6
Graph, Tree+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Mode and Queries
Medium6
Sorting, Array+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Point in Triangle
Medium6
Geometry, Sorting+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Hot and Cold
Medium6
Binary search, Geometry
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Interactive Factorial Guessing
Medium6
Math, Binary search
No attempts yet
Time limit
3.5s
Memory limit
1024 MB
Judgeable
King's Puzzle
Medium6
Greedy, Implementation+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Avant-garde Autocorrect
Medium6
Trie, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Exotic Elegance
Medium6
Sorting, Hash map+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
The Famous Pharaoh
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Destroying the spireGiven N, M, and a seed, compute the monster strength on floor N, a power tower of values g(k), modulo M.	Medium6	MathNumber theory+1	No attempts yet	1s	512 MB	Judgeable
Puang and the Staircase SequenceFind the fewest operations to empty a sequence of digits 1 to 9, where each step removes up to 3 end elements or a length-K staircase from an end.	Medium6	Dynamic programmingArray+1	No attempts yet	1s	1024 MB	Judgeable
Puang and CoinsFind the maximum coins from two non-overlapping squares in an N by N grid after subtracting each square's covered-cell count squared.	Medium6	Prefix sumBrute force+1	No attempts yet	1s	1024 MB	Judgeable
86 (Eighty-Six) 2Given an N by N grid of Legion units, decide whether Reginleif, starting from the marked cell, can defeat every Legion by moving diagonally and clearing up to two per move.	Medium6	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Puang and the TreadmillGiven X meters and T seconds, find the fewest presses of the speed buttons 0, 1, 4, and 8 that cover exactly X meters, or report -1.	Medium6	MathGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Alive or Dead?Simulate a player and two kinds of zombies on an N by N grid with walls, then report whether the player is alive after day D or the day they die.	Medium6	SimulationImplementation+1	No attempts yet	2s	1024 MB	Judgeable
Puang and Level UpFind the smallest K so that some right-down path from (0,0) to (N-1,N-1) collects at least R, where each cell adds the max of its K×K block.	Medium6	Binary searchDynamic programming+1	No attempts yet	3s	1024 MB	Judgeable
Toy MixingGiven N sequences of length M that cannot be split, find the order to join them so the concatenated sequence has the largest maximum subarray sum.	Medium6	Dynamic programmingBit manipulation+1	No attempts yet	1s	256 MB	Judgeable
Choosing a RoomGiven a graph with random edge weights, find all rooms from which some walk to school (vertex 1) has expected total time at most T.	Medium6	Shortest pathGraph	No attempts yet	2s	1024 MB	Judgeable
SNUPTIGiven M strings of length N, find disjoint letter sets A_1 to A_N whose Cartesian product is exactly the given strings, or report NO.	Medium6	Hash mapImplementation	No attempts yet	2s	1024 MB	Judgeable
Prime Calling GameTwo players take turns calling unused primes from their own ranges, and the player who cannot call one loses. Find the winner under optimal play.	Medium6	Game theoryNumber theory+1	No attempts yet	1s	512 MB	Judgeable
Melborp LacissalcCount length-n arrays over 0 to k-1 for which exactly t consecutive subarrays have a sum divisible by k, modulo 998244353.	Medium6	Dynamic programmingPrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
Find the PartsClara must answer where each small query rectangle sits in a large random grid, but the grid does not fit in 400 KiB of memory.	Medium6	MatrixString matching+1	No attempts yet	4s	2048 MB	Judgeable
One DimensionalBuild a permutation of 1 to N where no element sits between two others at the average of their values.	Medium6	Divide and conquerRecursion+1	No attempts yet	1s	512 MB	Judgeable
1 subtractionGiven N up to 1e9, find the fewest steps to reach 0, where each step subtracts 1 or erases one digit 1 and joins the remaining digits.	Medium6	StringGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Jump ShowdownCount the orders in which N circular panels can disappear, leaving 3, so that no player is ever forced off the arena. Print the count modulo 1e9+7.	Medium6	CombinatoricsDynamic programming+1	No attempts yet	3s	1024 MB	Judgeable
Building BombingGiven N buildings, find the fewest buildings to blow up so that building L is the K-th tallest among those visible from the left.	Medium6	Dynamic programmingGreedy	No attempts yet	3s	1024 MB	Judgeable
Connecting CablesGiven N axis-aligned rectangles, find the sum over all pairs of the minimum Manhattan distance between them, modulo 998244353.	Medium6	SortingPrefix sum	No attempts yet	2s	1024 MB	Judgeable
GridGiven an n by m grid with some 1 cells, find the fewest 0 cells to turn into 1 so the remaining 0 cells split into two or more groups, or report -1.	Medium6	ImplementationGeometry+1	No attempts yet	2s	1024 MB	Judgeable
Computation - Task 4Ten small tasks written in a custom instruction set: negation, absolute value, sigmoid, sorting 16 reals, XOR, bit conversion, and modular multiplication.	Medium6	ImplementationBit manipulation+1	No attempts yet	1s	1024 MB	Judgeable
Computation - Task 6Write an instruction-set program for ten fixed tasks, including XOR, a*b mod m, and sorting 16 reals, using only the listed operators.	Medium6	ImplementationBit manipulation+1	No attempts yet	1s	1024 MB	Judgeable
Good Segment SubsequencePick one integer from each chosen segment so the picks are nondecreasing. Find the maximum total weight and how many subsequences reach it.	Medium6	Dynamic programmingSegment tree	No attempts yet	2s	1024 MB	Judgeable
Which NumberGiven n and k primes, find the n-th positive integer that is divisible by none of the given primes.	Medium6	Binary searchNumber theory+1	No attempts yet	1s	1024 MB	Judgeable
Pretty chocolate and number gameGiven N white and N dark chocolates, find the highest score of a valid pretty chocolate arrangement, reported modulo 10^5.	Medium6	Dynamic programmingRecursion	No attempts yet	1s	1024 MB	Judgeable
Chocolate and the King GameCount the paths that start at the top-left cell of a 3 by N grid, visit every cell once under king moves, and end at the bottom-right cell, modulo 1e9.	Medium6	Dynamic programmingGraph	No attempts yet	1s	1024 MB	Judgeable
Food PoisoningFind the fewest weeks of meals, each a subset of n restaurants, that pin down the single bad restaurant while poisoning Mikey at most p times.	Medium6	MathCombinatorics	No attempts yet	1s	1024 MB	Judgeable
K-gap SubsequenceFind the length of the longest subsequence in which every pair of consecutive elements differs by at least k.	Medium6	Dynamic programmingSegment tree+1	No attempts yet	1s	1024 MB	Judgeable
Fast Random Message RelayGiven 12 students paired into fixed groups and the pairwise passing times, find the minimum time for a teacher's message to reach all students.	Medium6	Dynamic programmingBit manipulation+1	No attempts yet	3s	512 MB	Judgeable
Bad TreeFind the kth lexicographically smallest permutation of 1 to n that, inserted into a BST in order, produces a tree of height n-1.	Medium6	CombinatoricsDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Sum of a FunctionGiven s, e, and k, find the sum of the k smallest values of f(n), the smallest prime factor of each n from s to e.	Medium6	Number theorySorting	No attempts yet	1s	1024 MB	Judgeable
Median Inversion StringGiven n and k, output the median string(s) in lexicographic order among all length-n A/B strings with exactly k inversions.	Medium6	Dynamic programmingCombinatorics+1	No attempts yet	1s	1024 MB	Judgeable
Cooperative EscapeGiven a grid with Bonnie, Clyde, and a car, find the minimum total moves for both to reach the car without reusing any cell.	Medium6	GraphShortest path	No attempts yet	1s	1024 MB	Judgeable
Mountain ViewGiven a piecewise linear mountain outline and a camera width W, find the maximum average elevation over any window of width W.	Medium6	Sliding windowPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Alex is RightGiven two cities on a sphere, find the closest distance from the shortest great-circle flight to the North Pole and check whether it beats both endpoints.	Medium6	GeometryMath	No attempts yet	1s	1024 MB	Judgeable
Videogame ProbabilityGiven each item type's required count and catch probability, find the chance of collecting every required item within a maximum number of attempts.	Medium6	Dynamic programmingProbability	No attempts yet	1s	1024 MB	Judgeable
MultiplesGiven a and b, count the integers from 1 to b that are divisible by at least one integer from 2 to a, for up to 100 queries.	Medium6	Number theoryCombinatorics+1	No attempts yet	5s	1024 MB	Judgeable
Bouncing BunniesFind the fewest jumps from hill 1 to hill n where each jump changes temperature and humidity by the same amount, or report -1 if impossible.	Medium6	BFSHash map+1	No attempts yet	5s	1024 MB	Judgeable
Acquainted Through FriendsConnect N people into one group where a pair costs their gcd if it is above 1, otherwise the larger number, and find the minimum total cost.	Medium6	Number theoryGreedy+1	No attempts yet	0.5s	1024 MB	Judgeable
Squaring the TriangleGiven N vertices and edge probability p/q, find the expected square of the triangle count in a random graph, modulo 1e9+7, for T queries.	Medium6	MathCombinatorics+2	No attempts yet	5s	256 MB	Judgeable
Course SelectionAssign each student to as many of their 5 chosen courses as possible without exceeding any course limit, maximizing total enrollments, and print the assignment.	Medium6	GraphBFS	No attempts yet	1s	256 MB	Judgeable
Rain GaugeGiven a square of side s and a circle of radius r sharing the same center, find the area of the square covered by the circle, rounded to two decimals.	Medium6	GeometryMath	No attempts yet	1s	1024 MB	Judgeable
Jar GameTwo players alternately take k pebbles on turn k from one of three jars; find whether F, S, or a draw results under optimal play.	Medium6	Game theoryDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Build a Staircase (Large)Given N column heights, find the fewest columns to change so that every pair of adjacent columns differs in height by at most 1.	Medium6	Dynamic programmingImplementation	No attempts yet	2s	512 MB	Judgeable
Hansel and GretelCounts the ordered sequences of K zone card pairs, where each person never reuses a number and the two cards in a zone differ, modulo 1000000007.	Medium6	CombinatoricsMath	No attempts yet	1s	512 MB	Judgeable
Hyundai Mobis Air SuspensionFor each binary data string, count overlapping occurrences of the HIGH and LOW patterns, then print LOW, HIGH, or GOOD based on the difference.	Medium6	String matchingTrie	No attempts yet	1s	512 MB	Judgeable
Sum of Powers 1Given n and p, compute the sum of k^p for k from 1 to n, modulo 10^9+7, where n is up to 1e9 and p is up to 1000.	Medium6	MathNumber theory	No attempts yet	1s	512 MB	Judgeable
Bubble-bubble SortGiven n bubbles and a window size k, find how many hours of repeated sliding-window sorting it takes until the whole row is in order.	Medium6	ArrayMath	No attempts yet	2s	2048 MB	Judgeable
Adjusted AverageGiven n samples, remove at most k of them so the remaining average is as close as possible to a target value, and output the minimal absolute difference.	Medium6	SortingTwo pointers+1	No attempts yet	8s	1024 MB	Judgeable
Grinding GravelGiven gravel pieces and k equal-capacity grid cells, find the fewest splits needed so every cell is filled exactly.	Medium6	Bit manipulationDynamic programming	No attempts yet	4s	1024 MB	Judgeable
House NumberingOrient each street in a connected graph with n vertices and n edges so no intersection has two adjacent houses with the same number.	Medium6	GraphImplementation	No attempts yet	4s	1024 MB	Judgeable
Lowest LatencyGiven 10^5 random 3D integer points, find the minimum Euclidean distance between any pair of them.	Medium6	Divide and conquerSorting+1	No attempts yet	8s	1024 MB	Judgeable
CodepowersGiven an initial rating X and per-round changes A, count how many ratings in each query range [l, r) fall below K.	Medium6	Prefix sumSorting+1	No attempts yet	1.234s	1024 MB	Judgeable
Breeding BugsGiven n cicada periodicities, find the largest subset where no two chosen values, including a value paired with itself, sum to a prime.	Medium6	GraphNumber theory	No attempts yet	1s	1024 MB	Judgeable
Diabolic DoofenshmirtzFind the length of a circular lap by querying Perry's distance into the current lap at chosen times, within a limited number of measurements.	Medium6	MathNumber theory+1	No attempts yet	1s	1024 MB	Judgeable
Guessing GameDecide whether Alan's two Saturday and Sunday predictions can outscore every friend, given outcomes that are still open for the examinations.	Medium6	GraphImplementation	No attempts yet	3s	1024 MB	Judgeable
Enigmatic EnumerationCount the shortest cycles in an undirected graph with up to 3000 vertices and 6000 edges, where cycles with the same edge set are counted once.	Medium6	GraphBFS	No attempts yet	5s	1024 MB	Judgeable
Kapr2kar's r0utineGiven N, find an N-digit number with no zero digits whose second largest minus second smallest digit rearrangement equals itself, or report -1.	Medium6	MathImplementation+1	No attempts yet	1s	512 MB	Judgeable
ArrayGiven a label N, find the smallest row of Pascal's triangle that contains N, for up to 100000 queries.	Medium6	MathCombinatorics+1	No attempts yet	1s	1024 MB	Judgeable
MowerGiven a W by H lawn and a start square, decide whether the first player wins the game of alternately moving to adjacent unmown squares.	Medium6	Game theoryMath	No attempts yet	1s	1024 MB	Judgeable
ShamansGiven a grid-shaped parchment, find the largest number of congruent pieces (rotation allowed, no flipping) it can be cut into by sequential single-edge cuts.	Medium6	MatrixBrute force+1	No attempts yet	1s	1024 MB	Judgeable
Sequence Sum 2Given S and T up to 1e14, compute the sum of a_i for i from S to T, where a_i counts even divisors of i minus odd divisors.	Medium6	MathNumber theory	No attempts yet	2s	1024 MB	Judgeable
Match of the MillenniumGiven piles s_i and ratios p_i, find the fewest add or remove moves so every pile becomes a positive integer multiple of its p_i.	Medium6	SortingMath	No attempts yet	2s	1024 MB	Judgeable
Gomgomi's Diet Management 2Given a grid with obstacles, find the fewest new obstacles that cut every path from the top-left cell to the bottom-right cell.	Medium6	GraphBFS	No attempts yet	3.5s	1024 MB	Judgeable
Gomgomi's Last-Minute CrammingCount the orders for watching N lectures under prerequisite relations that form a forest, modulo 10^9+7.	Medium6	TreeCombinatorics+1	No attempts yet	1s	1024 MB	Judgeable
Fibonacci, the last sequence, and queriesApply Q range assignments that write Fibonacci numbers F_1, F_2, ... over a zero-filled array, then print the final array modulo 10^9+7.	Medium6	Segment treeMath	No attempts yet	1.2s	1024 MB	Judgeable
Shuffle GameGiven deck X and two decks P1 and P2, find the maximum LCS length between X and any interleaving of P1 and P2.	Medium6	Dynamic programmingString	No attempts yet	1.5s	1024 MB	Judgeable
Light PlacementGiven a brightness grid with walls, decide whether some light placement reproduces it, and find the minimum number of lights or report -1.	Medium6	BFSGreedy+1	No attempts yet	3s	1024 MB	Judgeable
NonogramCount the ways to color one nonogram row so its runs match the hint, given cells already marked as must-color (O) or must-stay-empty (X).	Medium6	Dynamic programmingPrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
Interplanetary Study MeetingGiven one wormhole per planet and each member's start planet, find the reachable venue that minimizes total wormhole cost, or print -1.	Medium6	GraphTree+1	No attempts yet	2s	1024 MB	Judgeable
Fair DivisionGiven n pirates and loot m, find the fraction f strictly between 0 and 1 with the smallest denominator that makes each pirate's total share an integer, or report impossible.	Medium6	Number theoryMath	No attempts yet	3s	1024 MB	Judgeable
Where Am I?Given a grid of markers, compute the expected and worst-case steps for a spiral search to locate an unknown start cell, and list the worst starts.	Medium6	SimulationBrute force+1	No attempts yet	2s	1024 MB	Judgeable
An Unbroken Heart 1Given N dragons with start heights H[i] and daily growth D[i], find for each k the maximum total cut length when at most one arrow is shot per day from day 1 to k.	Medium6	GreedySorting+1	No attempts yet	1.5s	1024 MB	Judgeable
NATO Phonetic Alphabet and QueriesEach step replaces every letter of S with its NATO word, and each query either applies x such steps or prints the p-th character.	Medium6	Dynamic programmingRecursion+1	No attempts yet	2s	1024 MB	Judgeable
Roha's FarmingGiven a grid of water values and p pipe materials, find the most water Roha can draw through a connected pipe network from Roha's plot.	Medium6	Dynamic programmingGraph+1	No attempts yet	2s	512 MB	Judgeable
Hanyang GawangGiven N karaoke machines with 2N players, where the higher skill always wins, print who sits on each machine after M rounds of winners and losers moving.	Medium6	SimulationImplementation	No attempts yet	1s	256 MB	Judgeable
Toward All Solve!Given N problems with difficulties and a page size K, count the days needed to solve all problems under the greedy chain rule on the unsolved-only page.	Medium6	Segment treeSimulation	No attempts yet	2s	1024 MB	Judgeable
Arms of a TreeFor each query, count ordered pairs of leaves (a, b) in a rooted tree whose depths sum to a value between W and V, modulo 1e9+7.	Medium6	TreeDFS+2	No attempts yet	5s	512 MB	Judgeable
HexominoGiven an N×M grid of numbers, find the largest sum of cells covered by one hexomino, where rotations and reflections are allowed.	Medium6	Brute forceBacktracking+1	No attempts yet	2s	512 MB	Judgeable
Going in CirclesFind the number n of carriages in a cycle by moving between carriages and toggling light switches, within 3n+500 steps, where 3 is at most n, at most 5000.	Medium6	ImplementationSimulation	No attempts yet	2s	1024 MB	Judgeable
High-quality TreeGiven a rooted binary tree, find the fewest leaves to remove so that every subtree has left and right depths differing by at most one.	Medium6	TreeDynamic programming	No attempts yet	3s	1024 MB	Judgeable
Last GuessGiven past Wordle guesses and their colors, the task is to output any lowercase word of length l that matches all the feedback.	Medium6	StringMatrix+1	No attempts yet	2s	1024 MB	Judgeable
ConstellationsRepeatedly merge the two closest constellations by average squared distance, breaking ties by age, and print the size of each new constellation.	Medium6	GreedySimulation+1	No attempts yet	10s	1024 MB	Judgeable
DifferencesGiven N strings of length M over A to D, find the index of the one whose Hamming distance to every other string is exactly K.	Medium6	StringBrute force	No attempts yet	2s	1024 MB	Judgeable
InsertionsInsert t into s at one position to maximize occurrences of p, then report the count, how many positions tie, and the smallest and largest such position.	Medium6	String matchingPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
SokobanGiven a Sokoban grid with up to 4 boxes, find the fewest box pushes that move every box onto a storage location.	Medium6	Shortest pathBFS+1	No attempts yet	10s	1024 MB	Judgeable
Displacing ParticlesFind the fewest attractor activations that move a particle from the center of a 2^N square to a given point (x, y).	Medium6	Bit manipulationMath+1	No attempts yet	1s	1024 MB	Judgeable
Numbers on Both SidesPick K cards from the two ends of a row, flip exactly L of them to their back numbers, and find the maximum possible total.	Medium6	Sliding windowHeap+1	No attempts yet	1s	1024 MB	Judgeable
Starflower Serenade (Hard)Find the expected number of seeds planted until each flower kind i blooms at least M_i times, printed as R modulo 998244353.	Medium6	Dynamic programmingProbability+1	No attempts yet	2s	512 MB	Judgeable
Sled track in the winter forestGiven an odd N, the task is to build the longest closed loop of path tiles in an N by N grid and output its length, a start tile, and the moves.	Medium6	ImplementationMatrix+1	No attempts yet	1s	512 MB	Judgeable
RestroomsGiven n restrooms and intervals that each need both a 0 and a 1 inside, decide whether such an arrangement exists and print one if it does.	Medium6	Dynamic programmingGreedy+1	No attempts yet	2s	1024 MB	Judgeable
MöbiusGiven arrays a and b, count the pairs (a_i, b_j) by the value of the Möbius function of their product, for -1, 0, and 1.	Medium6	Number theoryMath+1	No attempts yet	2s	1024 MB	Judgeable
Tree Plus 1Given a connected graph with N vertices and N edges, answer Q queries for the shortest path length between two vertices.	Medium6	GraphTree+1	No attempts yet	2s	1024 MB	Judgeable
Mode and QueriesFor each query range [l, r], find the shortest contiguous subarray inside it where some value appears at least K times, or -1 if none exists.	Medium6	SortingArray+1	No attempts yet	3s	256 MB	Judgeable
Point in TriangleCount the triangles formed by three of the N given points whose interior contains point P, with P on an edge not counted.	Medium6	GeometrySorting+2	No attempts yet	1s	512 MB	Judgeable
Hot and ColdFind a hidden integer point with coordinates up to 10^6 in at most 64 visits, using only closer, further, or same-distance answers.	Medium6	Binary searchGeometry	No attempts yet	3s	1024 MB	Judgeable
Interactive Factorial GuessingFind a hidden integer n using at most 10 queries, each asking for a chosen decimal digit of n!.	Medium6	MathBinary search	No attempts yet	3.5s	1024 MB	Judgeable
King's PuzzleBuild a connected simple graph on n vertices whose degrees take exactly k distinct values, or report NO if that is impossible.	Medium6	GreedyImplementation+1	No attempts yet	3s	1024 MB	Judgeable
Avant-garde AutocorrectGiven a frequency-ranked dictionary and a message, find the fewest key presses per word when autocomplete with tab, backspace, and single letters are allowed.	Medium6	TrieDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Exotic EleganceGiven an array, find the fewest cuts so that the resulting pieces can be rearranged into a non-decreasing sequence.	Medium6	SortingHash map+1	No attempts yet	3s	1024 MB	Judgeable
The Famous PharaohGiven the order of Paula-oh's cards, find the most rounds Vitic-oh can win when he may switch once to a rule where the smaller card wins.	Medium6	GreedySorting+1	No attempts yet	1s	1024 MB	Judgeable