Problems

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Total results29,335 problems

Making a Necklace
Medium6
Graph, Tree+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cookie-Loving Chunbae
Medium6
Dynamic programming, Segment tree+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Square Coloring
Medium6
Segment tree, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Groups of Strangers
Medium6
Graph, Backtracking+1
No attempts yet
Time limit
9s
Memory limit
1024 MB
Judgeable
Why Hobanwoo was late for school 2
Medium6
Graph, BFS+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
GPS on a Flat Earth
Medium6
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Meeting Point
Medium6
Shortest path, Graph+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Exam Study Planning
Medium6
Dynamic programming, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Locking Doors
Medium6
Graph, DFS+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Skewers
Medium6
Graph, Matrix
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cutting a Hypertriangle
Medium6
Combinatorics, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
B Road Band
Medium6
Dynamic programming, Sorting+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Double Up
Medium6
Dynamic programming, Array
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
A Complex Problem
Medium6
Graph, Union-find+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Add or Multiply
Medium6
Segment tree, Math
No attempts yet
Time limit
7s
Memory limit
1024 MB
Judgeable
Reapportionment
Medium6
Backtracking, Brute force+1
No attempts yet
Time limit
7s
Memory limit
1024 MB
Judgeable
Ribbon Road
Medium6
Geometry, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Scientific Grading
Medium6
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Assessment Disruption
Medium6
Implementation, Simulation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Fast Forward
Medium6
Prefix sum, Greedy+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Clubbing
Medium6
Two pointers, Bit manipulation+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Expressions
Medium6
Segment tree, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Fragmentation
Medium6
Number theory, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Golem Coordinated Derby
Medium6
Dynamic programming, Math
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Movers
Medium6
Graph, Array+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Proglute
Medium6
Dynamic programming, Graph+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Hate Coprime
Medium6
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Not Fun Problem
Medium6
Array, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Younger Sibling of a Right Triangle
Medium6
Geometry, Sorting+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Music Festival
Medium6
Dynamic programming, Segment tree+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Buying Gifts
Medium6
Sorting, Greedy
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Way Home
Medium6
Graph, Shortest path+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Wooden Bridge
Medium6
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Five Hundred Arhats
Medium6
Number theory, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Good arrays
Medium6
Number theory, Combinatorics+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Third Grader's Task
Medium6
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Melting Butter
Medium6
Sorting, Binary search
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Stacking Pizzas
Medium6
Combinatorics, Probability+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sauna
Medium6
Sorting, Segment tree+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Sad dances
Medium6
Array, Number theory+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
String and Permutation
Medium6
String, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Data Center Maintenance
Medium6
Graph, DFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Culture Contact
Medium6
String, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Houses in Berland
Medium6
Graph, BFS
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Team Building
Medium6
Math, Combinatorics
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cafeteria Queue
Medium6
Number theory, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Putnik
Medium6
Dynamic programming, Prefix sum
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Mikhail strikes back
Medium6
String, Dynamic programming+1
No attempts yet
Time limit
5s
Memory limit
4 MB
Judgeable
Multiplayer Snake
Medium6
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Absolem's Cloak
Medium6
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Honest Bureaucracy
Medium6
Binary search, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Escape Plan
Medium6
BFS, Graph+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Tree Inside a Tree
Medium6
Dynamic programming, Tree+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sakura Reflection
Medium6
Geometry, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Chocolate Cake
Medium6
Array, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sum of Intersection Sizes
Medium6
Combinatorics, Sorting+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
TSP
Medium6
Tree, Sorting+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Table Compression
Medium6
Sorting, Union-find+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
The Evil League of Evil
Medium6
Greedy, String+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Meeting Room Assignment
Medium6
Intervals, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Chef Geonggongi
Medium6
Bit manipulation, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Prerequisite Courses
Medium6
Graph, Union-find+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Beach Volleyball
Medium6
Queue, Simulation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Pixels Triumph
Medium6
Union-find, Matrix+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Tasty Cakes
Medium6
Dynamic programming, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tandem Copy
Medium6
String, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Fast Waiting
Medium6
Graph, Shortest path+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Making a Graph Acyclic
Medium6
BFS, Union-find
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
XNOR's Rebellion
Medium6
Bit manipulation, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Φ²
Medium6
Simulation, Linked list+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Exponentiation
Medium6
Math
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Lateral Damage
Medium6
Simulation, Greedy+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Hair Tying
Medium6
Array, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Nested Repetition Compression
Medium6
Dynamic programming, String matching+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Color Inversion on a Huge Chessboard
Medium6
Math, Implementation
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Kuglice (Christmas Ornaments)
Medium6
Dynamic programming, Game theory+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Cakes
Medium6
Graph, BFS
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Jumbled Stacks
Medium6
Simulation, Stack+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Doll Claw Machine
Medium6
Dynamic programming, Probability+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Touring Show
Medium6
Number theory, Array+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Shared Interests
Medium6
Bit manipulation, Dynamic programming+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Shoot! Take a Panorama
Medium6
Math, Geometry+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Padaengi's Great Escape from School!
Medium6
BFS, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Padaeng's Artwork
Medium6
Graph, Matrix+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
After the Wedding
Medium6
Math, Geometry+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Most Beautiful Christmas Tree
Medium6
Tree, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Someday, It Would Be Nice to Get Sorted
Medium6
Topological sort, Greedy+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Inverted Triangles
Medium6
Sorting, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Golomb Cages
Medium6
Backtracking, Matrix+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cookie Cutting
Medium6
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Placing Plates
Medium6
Backtracking, Matrix+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Breaking the Superconductor
Medium6
Math, Greedy
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Collection
Medium6
Segment tree, Prefix sum
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Raging River
Medium6
Graph, Shortest path
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Unterwave Distance
Medium6
Math, Sorting+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Minimum Longest Trip
Medium6
Dynamic programming, Topological sort+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Target Practice
Medium6
Simulation, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Prof. Pang Earning Aus
Medium6
Greedy, Simulation+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Electric power transmission
Medium6
Tree, Math
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Ranking
Medium6
Combinatorics, Dynamic programming+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Making a NecklaceGiven two graphs that each form a cycle with trees hanging off it, decide whether they are isomorphic and print the verdict.	Medium6	GraphTree+1	No attempts yet	1s	1024 MB	Judgeable
Cookie-Loving ChunbaeEach cookie has a position, a cost, and a free-range radius, and the task asks for the cheapest set of purchases whose ranges together cover all K cookies.	Medium6	Dynamic programmingSegment tree+1	No attempts yet	1s	1024 MB	Judgeable
Square ColoringGiven q horizontal, vertical, or diagonal coloring operations on an n by m board, count the cells painted black at least once.	Medium6	Segment treeSorting+1	No attempts yet	1s	1024 MB	Judgeable
Groups of StrangersSplit employees into at most three groups so that no two people who know each other share a group, or report Impossible if no split exists.	Medium6	GraphBacktracking+1	No attempts yet	9s	1024 MB	Judgeable
Why Hobanwoo was late for school 2Build an N-digit number starting with two-digit prime A and ending with two-digit prime B, where every adjacent two-digit pair is prime, or report -1.	Medium6	GraphBFS+2	No attempts yet	1s	1024 MB	Judgeable
GPS on a Flat EarthGiven towers with Manhattan distances to a user at integer coordinates, list every integer point that matches all distances exactly.	Medium6	MathImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Meeting PointGiven a weighted road graph, list every crossroad X where the shortest distance from P to X is twice the P-to-G distance and every shortest path to X passes through G.	Medium6	Shortest pathGraph+1	No attempts yet	0.5s	1024 MB	Judgeable
Exam Study PlanningGiven exams with start, early-exit, and full end times plus study needs, find the most exams you can pass by studying in free time before each exam starts.	Medium6	Dynamic programmingGreedy	No attempts yet	1s	1024 MB	Judgeable
Locking DoorsGiven rooms and one-way door constraints (each door locked only from one room), find the fewest exits to add so every door can be locked and you can leave.	Medium6	GraphDFS+1	No attempts yet	5s	1024 MB	Judgeable
SkewersGiven a grid of meat, scallion, and mushroom cells, find the most skewers that each take one adjacent meat and scallion in a line with a mushroom at one end.	Medium6	GraphMatrix	No attempts yet	1s	1024 MB	Judgeable
Cutting a HypertriangleCounts the ways to pick cut pieces of an M-dimensional hypertriangle of edge N that form a solid hypertriangle block, modulo 1e9+7.	Medium6	CombinatoricsMath+1	No attempts yet	1s	1024 MB	Judgeable
B Road BandPlace k access points on a midline to minimize the sum of squared distances from customers on two parallel streets to their nearest access point.	Medium6	Dynamic programmingSorting+1	No attempts yet	4s	1024 MB	Judgeable
Double UpGiven n powers of two, remove elements or merge equal adjacent pairs into one doubled value; find the largest number that can be obtained.	Medium6	Dynamic programmingArray	No attempts yet	3s	1024 MB	Judgeable
A Complex ProblemGiven subset and proper-subset relations between complexity classes, find the minimum and maximum number of distinct classes that can appear.	Medium6	GraphUnion-find+1	No attempts yet	3s	1024 MB	Judgeable
Add or MultiplyGiven a digit expression with + and × operators, report its value modulo 1e9+7 after each swap of digits, single operator flip, or flip of all operators.	Medium6	Segment treeMath	No attempts yet	7s	1024 MB	Judgeable
ReapportionmentGiven block populations in a rectangular town, decide whether the blocks can be split into W contiguous wards with equal total population.	Medium6	BacktrackingBrute force+1	No attempts yet	7s	1024 MB	Judgeable
Ribbon RoadGiven a simple polygon, Christie's position on its boundary, and a point her ray passes through, decide whether she is inside, outside, or cannot tell.	Medium6	GeometryImplementation	No attempts yet	1s	1024 MB	Judgeable
Scientific GradingGiven x and y in scientific notation, check whether four student answers to x+y, x-y, x*y, and x/y are within 1e-9 error of the true results.	Medium6	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Assessment DisruptionGiven N and W, output N distinct (word count, quality) pairs so that the Pareto-layer peeling procedure makes at least N^3/20 comparisons.	Medium6	ImplementationSimulation+1	No attempts yet	2s	1024 MB	Judgeable
Fast ForwardFor each start song in a circular playlist, count the ads that play when an ad can only follow a song and at least c seconds must pass between ads.	Medium6	Prefix sumGreedy+2	No attempts yet	2s	1024 MB	Judgeable
ClubbingCount the contiguous substrings of the schedule string that contain every member of at least one club.	Medium6	Two pointersBit manipulation+2	No attempts yet	2s	1024 MB	Judgeable
ExpressionsGiven an expression of positive integers with +, -, and * and a series of single-value changes, report whether the value is odd or even before and after each change.	Medium6	Segment treeMath+1	No attempts yet	2s	1024 MB	Judgeable
FragmentationFor each query range of machine characteristics, decide whether the product of those values is divisible by the number of laboratories k.	Medium6	Number theoryPrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
Golem Coordinated DerbyGiven N robot heights from 1 to 20, find the largest sum of gcds between neighbors when all robots line up in one row with the captain at one end.	Medium6	Dynamic programmingMath	No attempts yet	5s	1024 MB	Judgeable
MoversGiven labs with desks and monitors and neighbor links, process additions and report whether desks or monitors are more in a lab's closed neighborhood.	Medium6	GraphArray+1	No attempts yet	2s	1024 MB	Judgeable
ProgluteCount the non-crossing string sets on N circular pegs where every peg has two strings except two endpoint pegs with one, modulo 10^9+7.	Medium6	Dynamic programmingGraph+1	No attempts yet	2s	1024 MB	Judgeable
Hate CoprimeGiven x and y, add or subtract a z that shares a factor with the current x, at most twice, so that x becomes equal to y.	Medium6	Number theoryMath+1	No attempts yet	1s	1024 MB	Judgeable
Not Fun ProblemGiven N and M, build a length-N integer array with values in [0, 10^9] whose contiguous subarray sums cover every value from 0 to M and no value above M.	Medium6	ArrayMath	No attempts yet	2s	1024 MB	Judgeable
Younger Sibling of a Right TriangleFor each query (a, b), count the black points inside or on the boundary of the triangle with vertices (0, 0), (a, b), and (a, 0).	Medium6	GeometrySorting+1	No attempts yet	3s	1024 MB	Judgeable
Music FestivalGiven albums whose tracks play in fixed order, find the album order that maximizes how many tracks are louder than every track heard before them.	Medium6	Dynamic programmingSegment tree+1	No attempts yet	1s	1024 MB	Judgeable
Buying GiftsEach department gives one gift to either girlfriend; find the assignment that minimizes the gap between the two girlfriends' maximum gift prices.	Medium6	SortingGreedy	No attempts yet	2s	1024 MB	Judgeable
Way HomeFind the minimum number of performances needed to fly from city 1 to city n with starting money p, where each city pays a fixed amount per performance.	Medium6	GraphShortest path+1	No attempts yet	1s	1024 MB	Judgeable
Wooden BridgeCount the distinct bridges of W blocks whose total span is exactly L, where each block shifts by at most 1 unit from the one below, modulo 1e9+7.	Medium6	Dynamic programmingCombinatorics	No attempts yet	1s	1024 MB	Judgeable
Five Hundred ArhatsGiven n arhat strides, find non-negative step counts whose weighted sum is exactly K, or report -1 if no such walk exists.	Medium6	Number theoryDynamic programming+1	No attempts yet	2s	1024 MB	Judgeable
Good arraysCount arrays of length n with values up to c where each element is divisible by the next one, modulo 998244353.	Medium6	Number theoryCombinatorics+1	No attempts yet	2s	1024 MB	Judgeable
Third Grader's TaskCount the rearrangements of the symbols in s that are lexicographically less than t, modulo 998244353.	Medium6	CombinatoricsMath	No attempts yet	1s	1024 MB	Judgeable
Melting ButterEach butter spreads outward until its center height reaches 1. Find the largest whole number of seconds before any two spreading butters' intervals overlap.	Medium6	SortingBinary search	No attempts yet	2s	1024 MB	Judgeable
Stacking PizzasGiven a_i pizzas of each size i, sum over all stacking orders the number of pizzas visible from above, modulo 1000000007.	Medium6	CombinatoricsProbability+1	No attempts yet	1s	1024 MB	Judgeable
SaunaGiven n friend intervals and a limit t, choose Max's stay of length at most t to maximize friends he outranks minus friends who outrank him.	Medium6	SortingSegment tree+1	No attempts yet	2s	1024 MB	Judgeable
Sad dancesGiven permutations a and b, decide whether some positive power of a equals b, so that the dancers reach arrangement b after k minutes.	Medium6	ArrayNumber theory+1	No attempts yet	2s	1024 MB	Judgeable
String and PermutationGiven a string s and a hidden permutation p, find t where t[p_i] = s_i, using one batch of index-pair comparisons with as few pairs as possible.	Medium6	StringGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Data Center MaintenanceGiven data center maintenance hours and client pairs, find the fewest data centers to shift one hour later so every client keeps one copy reachable.	Medium6	GraphDFS+1	No attempts yet	1s	1024 MB	Judgeable
Culture ContactCut a string into the maximum number of substrings that all contain the same count of each letter.	Medium6	StringPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Houses in BerlandFind the shortest distance between two residential houses with different resident counts in a connected graph of crossroads and roads.	Medium6	GraphBFS	No attempts yet	2s	1024 MB	Judgeable
Team BuildingGiven n employees and team size k, find the fewest pairs that share a team on both days when each day is split into teams of k.	Medium6	MathCombinatorics	No attempts yet	1s	1024 MB	Judgeable
Cafeteria QueueGiven n, find the maximum number of expansion stages k and the per-stage push counts a_i that grow a two-student line to exactly n students.	Medium6	Number theoryMath	No attempts yet	2s	1024 MB	Judgeable
PutnikChoose the stations where the express Putnik stops so that the total number of passengers who switch to it is as large as possible.	Medium6	Dynamic programmingPrefix sum	No attempts yet	2s	1024 MB	Judgeable
Mikhail strikes backInsert the fewest letters into a string of up to 15000 characters to make it a palindrome, then print the count and one resulting palindrome.	Medium6	StringDynamic programming+1	No attempts yet	5s	4 MB	Judgeable
Multiplayer SnakeOn a wrap-around grid, two snakes move alternately; find the first move on which one snake can step onto the other snake's cell.	Medium6	MathImplementation	No attempts yet	2s	1024 MB	Judgeable
Absolem's CloakGiven an N by M cloak and K colors, find the color covering the most lattice points and the color covering the fewest, with their counts.	Medium6	MathImplementation	No attempts yet	2s	1024 MB	Judgeable
Honest BureaucracySplit at most K coins so the favorite with the smallest weight gets as many as possible, with strictly larger weights receiving strictly more.	Medium6	Binary searchSorting+1	No attempts yet	1s	1024 MB	Judgeable
Escape PlanFor each room, find the nearest exit left open after the K nearest exits close, breaking distance ties by the smaller room number.	Medium6	BFSGraph+1	No attempts yet	2s	1024 MB	Judgeable
Tree Inside a TreeCount the ways to delete vertices and edges from perfect binary tree T_N so the remainder is isomorphic to perfect binary tree T_K, modulo 1000000007.	Medium6	Dynamic programmingTree+1	No attempts yet	1s	1024 MB	Judgeable
Sakura ReflectionGiven N axes at angles A_i, decide whether reflecting across each axis exactly once can return the image to its start, and output one valid order if so.	Medium6	GeometryDynamic programming	No attempts yet	1s	1024 MB	Judgeable
Chocolate CakeGiven a cake of 2N pieces, add toppings of size M to pieces so that the largest taste gap between the two halves over all N cuts is as small as possible.	Medium6	ArrayPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Sum of Intersection SizesGiven N integer intervals, find for each k the sum of intersection sizes over all k-subsets of intervals, modulo 998244353.	Medium6	CombinatoricsSorting+1	No attempts yet	4s	1024 MB	Judgeable
TSPGiven K vertices in an implicit binary heap-shaped tree with up to 10^18 nodes, find the shortest walk that visits all of them.	Medium6	TreeSorting+1	No attempts yet	4s	1024 MB	Judgeable
Table CompressionReplace each value of an n by m table with a positive integer, keeping row and column order and equality, so that the largest new value is as small as possible.	Medium6	SortingUnion-find+1	No attempts yet	4s	1024 MB	Judgeable
The Evil League of EvilReplace each ? with ( or ) so the longest correct bracket subsequence of the string is as long as possible, then print the resulting string.	Medium6	GreedyString+1	No attempts yet	1s	1024 MB	Judgeable
Meeting Room AssignmentPick the most meetings from N time intervals so that K rooms never overlap, where a room needs a gap of at least one time unit between meetings.	Medium6	IntervalsDynamic programming+1	No attempts yet	2s	1024 MB	Judgeable
Chef GeonggongiGiven N values up to 511, answer Q range queries: the maximum of (XOR of a chosen subset in the range) plus the subset size.	Medium6	Bit manipulationDynamic programming+1	No attempts yet	2s	1024 MB	Judgeable
Prerequisite CoursesGiven a curriculum map of follow-up and prerequisite links, output the course actually taken each semester after redirecting the pick through the rules.	Medium6	GraphUnion-find+1	No attempts yet	2s	1024 MB	Judgeable
Beach VolleyballGiven N teams in a queue where the winner of each match stays and the loser goes to the back, find the two teams playing match K for each of Q queries, with K up to 10^18.	Medium6	QueueSimulation+1	No attempts yet	2s	1024 MB	Judgeable
Pixels TriumphGiven fragments that may be stored inverted, find the painting with the most white (0) pixels that fits all fragments, or report -1 when the fragments contradict each other.	Medium6	Union-findMatrix+1	No attempts yet	2s	1024 MB	Judgeable
Tasty CakesCount the shadings of an N x M grid whose unshaded cells can be exactly tiled by 1 x 2 dominoes, modulo 1000000007.	Medium6	Dynamic programmingBit manipulation	No attempts yet	1s	1024 MB	Judgeable
Tandem CopyGiven strings s and t, the task counts the valid substrings of s, where tandem copies of consecutive nucleotides build the sequences and stored forms have no two equal adjacent letters.	Medium6	StringDynamic programming+1	No attempts yet	1s	2048 MB	Judgeable
Fast WaitingFind the minimum time from stop 1 to stop N when Jaewon can make up to K routes depart immediately instead of waiting for their next scheduled bus.	Medium6	GraphShortest path+1	No attempts yet	2s	1024 MB	Judgeable
Making a Graph AcyclicVertices spread deletions by adjacency each time step, and the task asks for the first time the remaining graph has no cycle.	Medium6	BFSUnion-find	No attempts yet	1s	1024 MB	Judgeable
XNOR's RebellionGiven N numbers of B bits, pick a nonempty subsequence and fold it with B-bit XNOR from left to right to maximize the result.	Medium6	Bit manipulationDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Φ²Each day, microorganisms in a line absorb adjacent neighbors no bigger than themselves, front to back. Output the survivor's final size and starting index.	Medium6	SimulationLinked list+1	No attempts yet	1s	1024 MB	Judgeable
ExponentiationGiven n variables that start at 2023, apply m operations that set x_i to x_i raised to x_j, and answer comparisons between variables.	Medium6	Math	No attempts yet	3s	1024 MB	Judgeable
Lateral DamageLocate and sink all up to ten hidden aircraft carriers (length 5 each) on a grid of at most 100 by 100 using at most 2500 shots.	Medium6	SimulationGreedy+1	No attempts yet	2s	1024 MB	Judgeable
Hair TyingGiven values 0 to 3, pick subarrays and overwrite each with its XOR so no 3 remains, then print the minimum number of operations or -1.	Medium6	ArrayPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Nested Repetition CompressionGiven a lowercase string of up to 200 letters, output the shortest form using digit-prefixed parenthesized repeats, where nesting is allowed.	Medium6	Dynamic programmingString matching+1	No attempts yet	2s	1024 MB	Judgeable
Color Inversion on a Huge ChessboardAfter each row or column flip on an n by n checkerboard, report how many same-colored connected areas there are.	Medium6	MathImplementation	No attempts yet	4s	1024 MB	Judgeable
Kuglice (Christmas Ornaments)Two players alternately draw ornaments from either end of a box, scoring a point for each color drawn for the first time. Find both final scores under optimal play.	Medium6	Dynamic programmingGame theory+1	No attempts yet	0.5s	1024 MB	Judgeable
CakesChoose which cakes to bake so that total cake price minus the cost of all needed ingredients and tools is as large as possible.	Medium6	GraphBFS	No attempts yet	2s	1024 MB	Judgeable
Jumbled StacksMove top cards between capacity-limited stacks so cards 1 to n end up sorted bottom to top, packed into the lowest-indexed stacks.	Medium6	SimulationStack+1	No attempts yet	1s	1024 MB	Judgeable
Doll Claw MachineGiven p, c, and n, find the expected number of dolls after exactly k runs for each k up to n, modulo 1000000007.	Medium6	Dynamic programmingProbability+1	No attempts yet	2s	512 MB	Judgeable
Touring ShowFor each range [l, r], find the fewest triangles k such that 1 + kA_iA_j is a multiple of a for some pair i<j in the range, or -1.	Medium6	Number theoryArray+1	No attempts yet	1s	512 MB	Judgeable
Shared InterestsGiven N people's 24-bit interest masks, find for each person the other person sharing the most interests and sum those overlap counts.	Medium6	Bit manipulationDynamic programming+1	No attempts yet	3s	512 MB	Judgeable
Shoot! Take a PanoramaGiven weighted tree points and a rectangle, find the integer point outside the rectangle that minimizes the weighted sum of squared distances, and print that sum.	Medium6	MathGeometry+1	No attempts yet	1s	512 MB	Judgeable
Padaengi's Great Escape from School!Find whether Padaengi can reach (N, M), eat for K time units, and return to (1, 1) by time T without ever standing in a teacher's 8-cell watch range.	Medium6	BFSSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Padaeng's ArtworkGiven the 16-cell tetrahedra and the faces without holes, find the minimum number of bulbs so every tetrahedron is lit, where a bulb lights one tetrahedron or two adjacent ones through a hole.	Medium6	GraphMatrix+1	No attempts yet	1s	1024 MB	Judgeable
After the WeddingFind the limit of the average cut force when a piecewise linear solid of revolution is split into many equal-volume pieces, output modulo 998244353.	Medium6	MathGeometry+1	No attempts yet	1s	1024 MB	Judgeable
The Most Beautiful Christmas TreeCount the ways to place n distinct ornaments so each child is more beautiful than its parent, for each queried root, modulo 998244353.	Medium6	TreeDynamic programming+1	No attempts yet	2s	1024 MB	Judgeable
Someday, It Would Be Nice to Get SortedAdjacent coprime elements may be swapped any number of times; output the lexicographically smallest sequence that can be reached.	Medium6	Topological sortGreedy+1	No attempts yet	2s	1024 MB	Judgeable
Inverted TrianglesGiven N points, find the sum of doubled areas of all inverted triangles, where the middle-x point has the lowest y, modulo 1000000007.	Medium6	SortingPrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
Golomb CagesFill each row and column with the given numbers once, so every two-cell cage matches its result under +, -, *, or /.	Medium6	BacktrackingMatrix+1	No attempts yet	1s	1024 MB	Judgeable
Cookie CuttingGiven a rectangular dough sheet with circular bites removed, find how many copies of a polygonal cookie shape the remaining dough area can yield if the dough can be rearranged.	Medium6	GeometryMath	No attempts yet	1s	1024 MB	Judgeable
Placing PlatesGiven an a by b grid and p plates of size 1 by s, decide whether every plate can be placed horizontally or vertically without overlapping.	Medium6	BacktrackingMatrix+1	No attempts yet	1s	1024 MB	Judgeable
Breaking the SuperconductorFind the minimum total cost to cut an N gram block into K pieces of at least 1 gram each, where each cut costs the weight of the piece being cut.	Medium6	MathGreedy	No attempts yet	2s	1024 MB	Judgeable
CollectionGiven up to 10 test cases, add x coins to each type in a range, clear all coins in a range, and print the total value of the collection on each query.	Medium6	Segment treePrefix sum	No attempts yet	5s	1024 MB	Judgeable
Raging RiverFind the minimum total time to get all P people across when each plank can be crossed only once, or the fewest people who must stay behind.	Medium6	GraphShortest path	No attempts yet	2s	1024 MB	Judgeable
Unterwave DistanceFind the minimum gap between the cubed gravities of an alien and a human system, where one optional device shifts gravity in a neighborhood.	Medium6	MathSorting+1	No attempts yet	5s	1024 MB	Judgeable
Minimum Longest TripFor each town, find the longest trip on one-way roads with no cycles, breaking ties by the smallest label sequence, and report its length and label sum.	Medium6	Dynamic programmingTopological sort+2	No attempts yet	2s	1024 MB	Judgeable
Target PracticeGiven targets on a number line and a string of L, R, and F commands, find the most targets Bessie can hit after changing at most one command.	Medium6	SimulationPrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
Prof. Pang Earning AusGiven two stores with balloon and candy stocks and six exchange rates, find the most Au Prof. Pang can earn starting from 1 Au.	Medium6	GreedySimulation+1	No attempts yet	3s	1024 MB	Judgeable
Electric power transmissionOn a tree of wires where each wire has a threshold and divisor loss, answer queries for how much electricity reaches tower b when e units are sent from tower a.	Medium6	TreeMath	No attempts yet	3s	1024 MB	Judgeable
RankingGiven N contestants and K, count the distinct rank lists in which Geumseong finishes exactly K-th, with tied scores sharing a rank, modulo 1e9+7.	Medium6	CombinatoricsDynamic programming+1	No attempts yet	3s	1024 MB	Judgeable