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Total results29,413 problems

The theater begins with the actors
Medium6
Greedy, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Khan's Army
Medium6
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Longest Common Substring
Medium6
String, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Flag with Stars
Medium6
Math, Binary search+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Check Markers
Medium6
Greedy, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Role-Playing Game
Medium6
Greedy, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Brackets
Medium6
String, Stack+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Bicycle Race
Medium6
Sorting, Binary search+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Maxim's Triangle
Medium6
Math, Binary search+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Part Production
Medium6
Graph, Topological sort+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Gift
Medium6
Math, Brute force+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Lawn
Medium6
Math, Geometry+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Three-dimensional Tetris
Medium6
Simulation, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Homothety
Medium6
Geometry, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Glass Fence
Medium6
Geometry, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Fence
Medium6
Dynamic programming, Greedy+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Kitchen Layout
Medium6
Dynamic programming, Combinatorics+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Operations
Medium6
Math, String+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Kangaroo Leo
Medium6
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Pekka's Student Years
Medium6
Greedy, Two pointers+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bank Cards
Medium6
Greedy, String+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Buses
Medium6
Graph, Greedy+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Stalker
Medium6
Graph, BFS+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Old Fortress
Medium6
Geometry, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Two Rectangles
Medium6
Implementation, Brute force+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Division
Medium6
Prefix sum, Hash map+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Gathering Honey
Medium6
Prefix sum, Greedy+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Two Teams
Medium6
Tree, Dynamic programming
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Hyper-Rectangle
Medium6
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Gahui and Process 1
Medium6
Heap, Simulation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Gahui and Resource Play
Medium6
Simulation, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Gahui and the Read-Write Game
Medium6
Simulation, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Reverse Gahui and Process 1
Medium6
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Pinball
Medium6
Simulation, Implementation+1
No attempts yet
Time limit
2s
Memory limit
64 MB
Judgeable
Do You Know Your ABCs?
Medium6
Brute force, Math+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Acowdemia
Medium6
Binary search, Greedy+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Acowdemia III
Medium6
Greedy, Graph+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Bread First Search
Medium6
Graph, BFS+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Contact Tracing
Medium6
Graph, BFS+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Promotion
Medium6
Dynamic programming, Bit manipulation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Hat Game
Medium6
Implementation, Bit manipulation+2
No attempts yet
Time limit
1.5s
Memory limit
128 MB
Judgeable
Innoforest
Medium6
Greedy, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Life in Innopolis
Medium6
String, String matching+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Aerobatic Flight
Medium6
Dynamic programming, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Even Palindrome
Medium6
Dynamic programming, Hash map+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Meeting in the Middle
Medium6
Graph, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Part Rental Log
Medium6
Hash map, String+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Problem Recommendation System Version 2
Medium6
Implementation, Hash map+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Shell
Medium6
Graph, Topological sort+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Treasure
Medium6
Stack, String+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Mean
Medium6
Dynamic programming, Math+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Financial Report
Medium6
Dynamic programming, Segment tree
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Japanese Game
Medium6
Greedy, String+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
King's Task
Medium6
Graph, BFS+2
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
svemir
Medium6
Binary search, Geometry+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Robot
Medium6
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Bus Lines
Medium6
Graph, Greedy+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Alphabet Contest
Medium6
Greedy, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Mutating DNA
Medium6
Prefix sum, String+2
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Teleports
Medium6
Graph, BFS+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Banana Box Purchases
Medium6
Simulation, Sorting+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Ceremonial Parade
Medium6
Math, Number theory+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Knapsack Problem
Medium6
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
On a Distant Amazon
Medium6
Graph, Greedy+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Visiting with Gifts
Medium6
Simulation, Queue+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
King and Queen
Medium6
Geometry, Math+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Changyoung and the Commute Home
Medium6
Binary search, BFS+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Kepler
Medium6
Math, Greedy+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Molecule
Medium6
String, Greedy+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Traffic Jam
Medium6
Simulation, Math+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Space Expedition
Medium6
Sorting, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Trapezoid Map and Trapezoids
Medium6
Combinatorics, Math+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Siege
Medium6
Dynamic programming, Sorting+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Coins
Medium6
Dynamic programming, Math+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Clock
Medium6
Implementation, Math+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Kill the Pig
Medium6
Geometry, Math+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Multiply
Medium6
Math, Implementation+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Tiny - 2
Medium6
Dynamic programming, Simulation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Rectangles
Medium6
Geometry, Sorting
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Gahui and the Bank
Medium6
Queue, Simulation+1
No attempts yet
Time limit
1.5s
Memory limit
512 MB
Judgeable
Information Merchant Hoseok
Medium6
Heap, Hash map+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Hosuk Saurus
Medium6
Graph, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Dividing Candy
Medium6
Math, Greedy+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Excellent Views
Medium6
Stack, Array+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Job Allocator
Medium6
Hash map, Implementation+2
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Lola's Schedule
Medium6
Intervals, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Small Schedule
Medium6
Binary search, Greedy+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
shortestpathcube
Medium6
Geometry, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
base2i
Medium6
Math, Number theory+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Palindrome Numbers
Medium6
String, Greedy+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Chuck's Challenge
Medium6
BFS, Bit manipulation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Trail Maintenance
Medium6
Minimum spanning tree, Graph+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Comparing Parenthesis Values
Medium6
String, Stack+2
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Antibody Recognition
Medium6
BFS, DFS+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Arrow Dice
Medium6
Simulation, Geometry+1
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Mountain View
Medium6
Geometry, Sorting+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Poisonous Swamp
Medium6
Shortest path, Graph+2
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Hyakunin Isshu
Medium6
Trie, String+1
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Mansion and Deliveries
Medium6
Dynamic programming, Greedy+2
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Let's Solve a Geometry Problem
Medium6
Number theory, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
The theater begins with the actorsGiven M acts, each listing actors who performed, find for every actor the earliest act after which the actor can be matched to a portrait.	Medium6	GreedyImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Khan's ArmyCounts the permutations of 1 to N in which the K bodyguard numbers form a longest increasing subsequence.	Medium6	Dynamic programmingBit manipulation+1	No attempts yet	1s	1024 MB	Judgeable
Longest Common SubstringGiven up to 1000 lowercase strings of length at most 100, find the length of the longest substring that appears in every string.	Medium6	StringDynamic programming+2	No attempts yet	1s	1024 MB	Judgeable
Flag with StarsFind rows and a maximum row size so that n stars form alternating rows differing by one, minimizing \|rows - max row size\|.	Medium6	MathBinary search+2	No attempts yet	1s	512 MB	Judgeable
Check MarkersCan markers be removed in different-color pairs, each containing a spent one, until only one color remains?	Medium6	GreedyMath+1	No attempts yet	2s	512 MB	Judgeable
Role-Playing GameEach of n characters has an unknown level from 1 to m; find the fewest white and red badges (white worth 1, red worth k) that cover every possible set of levels.	Medium6	GreedyMath+2	No attempts yet	2s	512 MB	Judgeable
BracketsGiven a regular bracket sequence, count the ordered position pairs where one opening and one closing bracket can be inserted so the result is again regular.	Medium6	StringStack+2	No attempts yet	1s	512 MB	Judgeable
Bicycle RaceEach cyclist starts at position x_i with constant speed v_i; find the time t when the spread between the frontmost and rearmost cyclist is smallest, and that spread.	Medium6	SortingBinary search+2	No attempts yet	2s	512 MB	Judgeable
Maxim's TriangleGiven a sequence of probe frequencies and whether each is closer to or farther from an unknown value, find the min and max possible value of that unknown.	Medium6	MathBinary search+2	No attempts yet	2s	512 MB	Judgeable
Part ProductionGiven part build times and a DAG of prerequisites, output the minimum time to build part 1, the number of parts built, and a valid production order.	Medium6	GraphTopological sort+2	No attempts yet	2s	512 MB	Judgeable
GiftGiven n unit cells of paper, find integer box dimensions whose total surface area fits within n and whose volume is as large as possible.	Medium6	MathBrute force+2	No attempts yet	2s	512 MB	Judgeable
LawnCount the integer lattice points inside an axis-aligned rectangle that also lie within distance r of a given point.	Medium6	MathGeometry+2	No attempts yet	2s	512 MB	Judgeable
Three-dimensional TetrisSimulate pieces of unit cubes on a W x D x H grid, applying translations and 90-degree rotations about axes, then report every occupied cube.	Medium6	SimulationImplementation+2	No attempts yet	2s	512 MB	Judgeable
HomothetyGiven two simple n-gons in counterclockwise order, decide whether some homothety maps the first onto the second, and if so output its center and coefficient.	Medium6	GeometryMath+2	No attempts yet	2s	512 MB	Judgeable
Glass FenceGiven a rectilinear polygon of 1 km blocks with a swamp inside, find the shortest block-aligned fence around the swamp, breaking ties by smallest enclosed area.	Medium6	GeometryImplementation	No attempts yet	2s	512 MB	Judgeable
FenceGiven up to 50 disjoint unpainted segments on a fence, a tanker at position 0, and a bucket holding k boards, find the shortest walk that repaints every unpainted board and returns to the tanker.	Medium6	Dynamic programmingGreedy+2	No attempts yet	1s	1024 MB	Judgeable
Kitchen LayoutCount the ways to split distinct cabinet types into two groups and order each group along one of the two kitchen walls.	Medium6	Dynamic programmingCombinatorics+2	No attempts yet	2s	1024 MB	Judgeable
OperationsParse two decimal numbers in integer.nonrepeating(repeating) notation and print their sum as a reduced fraction p/q.	Medium6	MathString+2	No attempts yet	1s	1024 MB	Judgeable
Kangaroo LeoFind the fewest jumps Leo needs to leave a canyon with pillars, where each jump rises p, moves q sideways, and drops at most r.	Medium6	BFSGraph+1	No attempts yet	1s	1024 MB	Judgeable
Pekka's Student YearsTwo trains of N cars each hold matched cargo types; shifting either train one car forward costs one unit, so find the minimum total shifts to align and unload all cars.	Medium6	GreedyTwo pointers+1	No attempts yet	1s	1024 MB	Judgeable
Bank CardsGiven a number X as a digit string, find the smallest positive integer N that cannot be formed as a subsequence of X's digits.	Medium6	GreedyString+2	No attempts yet	2s	1024 MB	Judgeable
BusesGiven M daily bus trips with cities and clock times, find the minimum number of buses to run the schedule forever, or -1 if impossible.	Medium6	GraphGreedy+2	No attempts yet	2s	1024 MB	Judgeable
StalkerGiven K undirected graphs on N vertices, find the fewest graph switches needed to walk from vertex 1 to vertex N, starting with no graph loaded.	Medium6	GraphBFS+2	No attempts yet	2s	1024 MB	Judgeable
Old FortressGiven n disjoint arcs on a circle of radius r, find the minimum perimeter of a convex fence that encloses all the arcs.	Medium6	GeometrySorting+1	No attempts yet	2s	1024 MB	Judgeable
Two RectanglesGiven a grid of black and white cells, decide whether the black cells form exactly two non-overlapping axis-aligned rectangles, and if so, label them with 'a' and 'b'.	Medium6	ImplementationBrute force+2	No attempts yet	2s	512 MB	Judgeable
DivisionCount ways to cut a sequence into four nonempty contiguous parts with equal sums, allowing negative values.	Medium6	Prefix sumHash map+2	No attempts yet	1s	512 MB	Judgeable
Gathering HoneyPlace two bees and one hive on distinct positions in a row; each bee collects honey from every cell it passes (start cell excluded, shared cells counted twice), and you maximize the total.	Medium6	Prefix sumGreedy+2	No attempts yet	1s	512 MB	Judgeable
Two TeamsGiven a rooted tree of employees with signed skill values, pick two disjoint teams led by different employees to maximize the total skill of both.	Medium6	TreeDynamic programming	No attempts yet	2s	512 MB	Judgeable
Hyper-RectangleGiven N cards that each add a value to one of four variables, pick exactly K cards and an order that maximizes the product of the four variables.	Medium6	GreedySorting+2	No attempts yet	1s	512 MB	Judgeable
Gahui and Process 1Simulate a priority scheduler that each second picks the process with the largest priority (ties broken by smallest id), then bumps every other process's priority by 1 and decrements the chosen one's remaining time, printing the chosen id for T seconds.	Medium6	HeapSimulation+2	No attempts yet	1s	512 MB	Judgeable
Gahui and Resource PlaySimulate a card game where players draw operation cards from a deck or replay a held card, and report which card id is performed each turn.	Medium6	SimulationImplementation+2	No attempts yet	2s	512 MB	Judgeable
Gahui and the Read-Write GameGiven N players' card sequences and each card's operations, enumerate every distinct final string over all permutations of the cards, printing them in ASCII order.	Medium6	SimulationImplementation+2	No attempts yet	2s	512 MB	Judgeable
Reverse Gahui and Process 1Given the sequence of process ids the scheduler picked each second, recover each process's initial run time and priority that reproduce that sequence.	Medium6	ImplementationSimulation+1	No attempts yet	1s	512 MB	Judgeable
PinballGiven the existing plates and the launch point A and target B, find the empty cell and mirror type for one added plate that gives the shortest path from A to B.	Medium6	SimulationImplementation+1	No attempts yet	2s	64 MB	Judgeable
Do You Know Your ABCs?Given 4 to 7 distinct integers, count how many triples (A,B,C) with A<=B<=C have every given number among A, B, C and their pairwise and total sums.	Medium6	Brute forceMath+2	No attempts yet	1s	512 MB	Judgeable
AcowdemiaGiven N papers with citation counts, up to K surveys each citing at most L distinct papers, find the maximum achievable h-index.	Medium6	Binary searchGreedy+2	No attempts yet	1s	512 MB	Judgeable
Acowdemia IIIOn a grid of cows, grass, and empty cells, each grass cell can pair two cows adjacent to it; maximize the number of disjoint cow pairs.	Medium6	GreedyGraph+2	No attempts yet	1s	512 MB	Judgeable
Bread First SearchFind the minimum number of new roads needed so that visiting towns in order 1 to N is a valid breadth first search starting from town 1.	Medium6	GraphBFS+2	No attempts yet	1s	512 MB	Judgeable
Contact TracingGiven daily meetings, initial infections, and test results on day 101, label each person as certainly infected, certainly healthy, or unknown.	Medium6	GraphBFS+2	No attempts yet	1s	256 MB	Judgeable
PromotionGiven n daily packages, each covering a subset of m object types at a fixed price, find the cheapest set of packages whose union covers all m types.	Medium6	Dynamic programmingBit manipulation+2	No attempts yet	1s	512 MB	Judgeable
Hat GameDevise a strategy for a line of N people (N ≤ 10) who each see the hats in front of them and say a number 0 to 63, maximizing correct guesses across T games.	Medium6	ImplementationBit manipulation+2	No attempts yet	1.5s	128 MB	Judgeable
InnoforestDecide whether row and column waterings can turn grid a into grid b, and if so output the operations, each adding a positive amount to a whole row or column.	Medium6	GreedyImplementation+2	No attempts yet	2s	512 MB	Judgeable
Life in InnopolisGiven a DNA string, count positions i where the suffix at i is lexicographically smaller than the suffix at i+1.	Medium6	StringString matching+2	No attempts yet	1s	512 MB	Judgeable
Aerobatic FlightGiven an N by M grid of scores, find a climb from the bottom-left cell moving only up or right and a descent from the switch cell to the bottom-right cell moving only down or right that maximize the sum of visited cells.	Medium6	Dynamic programmingPrefix sum+1	No attempts yet	1s	512 MB	Judgeable
Even PalindromeSplit the sequence into the maximum number of contiguous parts, each of even length and equal to its own reverse, or report -1 if impossible.	Medium6	Dynamic programmingHash map+2	No attempts yet	1s	512 MB	Judgeable
Meeting in the MiddleGiven a directed weighted graph and a set of K home cities, pick every city X such that the maximum over all homes of the round-trip distance to X and back is minimized, printing the chosen city numbers in ascending order.	Medium6	GraphShortest path+2	No attempts yet	1s	512 MB	Judgeable
Part Rental LogParse a chronological log of borrow and return events, match them per person and part, and sum fines for rentals that exceed the allowed period, then print nicknames in lexicographic order.	Medium6	Hash mapString+2	No attempts yet	1s	512 MB	Judgeable
Problem Recommendation System Version 2Maintain a problem list supporting add and remove, plus queries for the hardest or easiest problem by category, overall, or above or below a difficulty threshold.	Medium6	ImplementationHash map+2	No attempts yet	1s	512 MB	Judgeable
ShellCount paths from vertex 1 to vertex n in a DAG that visit a given list of p vertices in order, modulo 1e9+7, with multiedges counted separately.	Medium6	GraphTopological sort+2	No attempts yet	1s	512 MB	Judgeable
TreasureRepeatedly delete the first run of exactly K equal consecutive letters until no such run remains, and print the final string.	Medium6	StackString+2	No attempts yet	1s	512 MB	Judgeable
MeanRepeatedly merge two adjacent numbers into the floor of their mean until one number remains; find the largest possible final value.	Medium6	Dynamic programmingMath+2	No attempts yet	1s	512 MB	Judgeable
Financial ReportChoose days that include the last day N, with consecutive picks at most D days apart, to maximize how many chosen days set a new record-high sales amount.	Medium6	Dynamic programmingSegment tree	No attempts yet	2s	512 MB	Judgeable
Japanese GameGiven a mask of n cells marking the cells filled in every solution, find any run-length profile that produces exactly that mask, or report -1.	Medium6	GreedyString+1	No attempts yet	1s	512 MB	Judgeable
King's TaskGiven a permutation of 1 to 2n, find the fewest swaps of adjacent pairs or of the two halves needed to sort it, or report that sorting is impossible.	Medium6	GraphBFS+2	No attempts yet	3s	512 MB	Judgeable
svemirFind an unknown cube in an N by N by N grid using at most 200 distance-comparison queries, each telling whether a move brought the ship closer to or farther from the target.	Medium6	Binary searchGeometry+2	No attempts yet	1s	512 MB	Judgeable
RobotFind a sequence of at most 700 moves that drives a robot on a walled grid to (0,0) from either of two unknown starting cells.	Medium6	BFSGraph+2	No attempts yet	1s	512 MB	Judgeable
Bus LinesBuild a connected graph on vertices 1..n with m edges whose endpoint sums are all distinct, or report that this is impossible.	Medium6	GraphGreedy+2	No attempts yet	1s	512 MB	Judgeable
Alphabet ContestSplit string s into the fewest alphabetical subsequences, one per participant, with at most k skipped letters in total, or report Impossible.	Medium6	GreedyDynamic programming+1	No attempts yet	1s	512 MB	Judgeable
Mutating DNAGiven two DNA strings over A, T, C, answer queries asking the minimum number of swaps to turn one substring into the other, or -1 if impossible.	Medium6	Prefix sumString+2	No attempts yet	1s	2048 MB	Judgeable
TeleportsGiven n points, each teleport reflects your position across it; decide whether you can reach the target point from the start.	Medium6	GraphBFS+2	No attempts yet	2s	256 MB	Judgeable
Banana Box PurchasesSimulate Gru's account: at each shipping time buy if affordable, otherwise try to pay the higher price at delivery, and count purchases.	Medium6	SimulationSorting+2	No attempts yet	2s	256 MB	Judgeable
Ceremonial ParadeBuild an n by n matrix of primes using exactly k distinct primes so every row product and every column product has the same number of divisors.	Medium6	MathNumber theory+2	No attempts yet	2s	256 MB	Judgeable
Knapsack ProblemGiven a modulus m up to 10^18, build a knapsack test with N up to 200 and W up to 500 where the subset count for weight W is divisible by m, or print -1.	Medium6	Dynamic programmingCombinatorics+1	No attempts yet	2s	256 MB	Judgeable
On a Distant AmazonGiven n women, construct a mother-daughter forest where exactly a women have at least one daughter and exactly b are someone's daughter, or report impossible.	Medium6	GraphGreedy+2	No attempts yet	2s	256 MB	Judgeable
Visiting with GiftsSimulate m gift visits where each visitor gives their earliest received gift, or buys a new one if they hold none, and report whether the host receives a gift they originally bought.	Medium6	SimulationQueue+2	No attempts yet	2s	256 MB	Judgeable
King and QueenGiven an n by m board with a queen on (x, y), count the connected regions of cells the king (no diagonal moves) can reach without stepping on a queen-attacked cell, and print each region's size sorted.	Medium6	GeometryMath+1	No attempts yet	2s	256 MB	Judgeable
Changyoung and the Commute HomeGiven an N by N grid of elevations, find the smallest possible value of the maximum absolute elevation difference along a path from the top-left cell to the bottom-right cell, moving up, down, left, or right.	Medium6	Binary searchBFS+2	No attempts yet	2s	512 MB	Judgeable
KeplerGiven an n by m panel, fold it down to 1 by 1 where each halving is free and each odd-side cut costs the other dimension; find the minimum total laser time.	Medium6	MathGreedy+2	No attempts yet	2s	256 MB	Judgeable
MoleculeEach molecule is a cyclic string of b and w atoms. Find the minimum number of cut-and-paste moves that make all b's and all w's form one contiguous block each.	Medium6	StringGreedy+2	No attempts yet	2s	256 MB	Judgeable
Traffic JamGiven the initial positions, lengths, and speeds of cars ahead on a straight road, find when the professor's car reaches coordinate S, given cars slow down to the car ahead when L meters apart.	Medium6	SimulationMath+2	No attempts yet	2s	256 MB	Judgeable
Space ExpeditionAssign each of n ships to fuel type 1 (burning a_i) or type 2 (burning b_i) so that both fuel totals stay within k(n+1), where a_i + b_i = 4k.	Medium6	SortingPrefix sum+1	No attempts yet	2s	256 MB	Judgeable
Trapezoid Map and TrapezoidsCount sets of four segments that can form a non-degenerate isosceles trapezoid, where the parallel bases and equal legs come from the chosen lengths.	Medium6	CombinatoricsMath+2	No attempts yet	2s	256 MB	Judgeable
SiegePick artifacts whose activation costs total at most A so that the enemy, spending B merlins on the cheapest destructions first, leaves the most standing.	Medium6	Dynamic programmingSorting+1	No attempts yet	2s	256 MB	Judgeable
CoinsCount ordered pairs of coin denominations (x, y) such that some combination of coins, where each coin of value y he counted as value x, sums to T while his count sums to S.	Medium6	Dynamic programmingMath+2	No attempts yet	2s	256 MB	Judgeable
ClockGiven a visible arc of the clock face and optional known hand positions, count how many valid hand configurations match the constraints.	Medium6	ImplementationMath+2	No attempts yet	2s	256 MB	Judgeable
Kill the PigA bird flies along a parabola until the player taps, then continues along the tangent line; find the tap time so the path passes through the pig, or report Ok or Impossible.	Medium6	GeometryMath+2	No attempts yet	2s	256 MB	Judgeable
MultiplyMultiply two non-negative integers given as decimal strings of up to 50,000 digits each and print the product without leading zeros.	Medium6	MathImplementation+2	No attempts yet	2s	128 MB	Judgeable
Tiny - 2Given a sequence of unrotatable Tiny pieces, choose a column for each so that all N pieces fit inside a 9 by 9 container without exceeding its top.	Medium6	Dynamic programmingSimulation+1	No attempts yet	1s	512 MB	Judgeable
RectanglesFind the integer point B on the top or right edge so that segment AB from the origin crosses the most of N axis-parallel rectangles.	Medium6	GeometrySorting	No attempts yet	1s	512 MB	Judgeable
Gahui and the BankSimulate a round-robin queue where each customer gets at most T seconds per turn and later arrivals join the back, then report who is served at each second from 0 to W-1.	Medium6	QueueSimulation+1	No attempts yet	1.5s	512 MB	Judgeable
Information Merchant HoseokProcess queries where gorillas gain information values and Hoseok buys the b most valuable pieces from a named gorilla, and report the total value bought.	Medium6	HeapHash map+2	No attempts yet	2s	512 MB	Judgeable
Hosuk SaurusA cow moves on a grid where allowed directions cycle with the move number (any, vertical only, horizontal only); find the minimum total cell shock from start to exit.	Medium6	GraphShortest path+2	No attempts yet	1s	512 MB	Judgeable
Dividing CandyGiven N boxes whose candy counts are powers of 2, decide whether the boxes can be split into two nonempty groups whose sums are both powers of 2.	Medium6	MathGreedy+2	No attempts yet	1s	1024 MB	Judgeable
Excellent ViewsFor each building i, count buildings j such that no building within distance \|i-j\| of i is taller than Hj.	Medium6	StackArray+2	No attempts yet	1s	1024 MB	Judgeable
Job AllocatorProcess machine connect, disconnect, and job query events, counting connected machines that hold at least the requested counts of each resource type.	Medium6	Hash mapImplementation+2	No attempts yet	1.5s	1024 MB	Judgeable
Lola's ScheduleChoose the earliest first-dose time T within 480 minutes that minimizes how many of the recurring doses at T, T+X, T+2X, ... fall inside Lola's non-overlapping activities.	Medium6	IntervalsMath+2	No attempts yet	1s	1024 MB	Judgeable
Small ScheduleGiven M identical machines, S jobs of length 1 and L jobs of length Q, find the minimum makespan to schedule all jobs.	Medium6	Binary searchGreedy+2	No attempts yet	1s	512 MB	Judgeable
shortestpathcubeFind the shortest path along the surface of a 100 by 100 by 100 cube from a given surface point to the opposite corner.	Medium6	GeometryShortest path+2	No attempts yet	1s	512 MB	Judgeable
base2iRepresent the Gaussian integer x + iy in base 2i, using digits 0 to 3 and exactly one fractional digit, and return it as a string.	Medium6	MathNumber theory+2	No attempts yet	1s	512 MB	Judgeable
Palindrome NumbersGiven up to 50 positive integers of at most 80 digits, output for each the smallest decimal palindrome that is greater than or equal to it.	Medium6	StringGreedy+2	No attempts yet	1s	512 MB	Judgeable
Chuck's ChallengeFind the fewest doors that must be opened to walk from the entrance to the exit of a grid maze, where keys unlock doors and unstable floors collapse after the player leaves them.	Medium6	BFSBit manipulation+2	No attempts yet	1s	512 MB	Judgeable
Trail MaintenanceAfter each new wild animal trail is added, print the minimum total length of maintained trails that connects all N fields, or -1 if no such set exists.	Medium6	Minimum spanning treeGraph+1	No attempts yet	1s	512 MB	Judgeable
Comparing Parenthesis ValuesGiven two valid parenthesis strings, compare the values defined by f(()) = 1, f((X)) = 2 f(X), and f(XY) = f(X) + f(Y).	Medium6	StringStack+2	No attempts yet	4s	1024 MB	Judgeable
Antibody RecognitionGiven two grids, decide whether the second can result from picking one start cell, flooding its monochromatic connected component, and repainting that whole component one color.	Medium6	BFSDFS+2	No attempts yet	1s	1024 MB	Judgeable
Arrow DiceFold each 5x5 arrow net into a cube, then for every pair of dice find the fewest faces with mismatched arrows over all cube rotations.	Medium6	SimulationGeometry+1	No attempts yet	8s	512 MB	Judgeable
Mountain ViewGiven N semicircles on a line, each centered at c_i with radius r_i, answer Q queries asking the maximum height among semicircles covering a given x.	Medium6	GeometrySorting+2	No attempts yet	2s	512 MB	Judgeable
Poisonous SwampOn a 100x100 grid with one non-poisonous rectangle, find the minimum total damage (entries into swamp cells) to visit N destinations in order.	Medium6	Shortest pathGraph+2	No attempts yet	8s	512 MB	Judgeable
Hyakunin IsshuReorder N cards so the sum of longest common prefixes between adjacent cards is minimal, then print the lexicographically smallest such deck.	Medium6	TrieString+1	No attempts yet	8s	512 MB	Judgeable
Mansion and DeliveriesDeliveries arrive at sorted times; each round trip to the door costs 2M, so pick a subset of deliveries to answer while maximizing time spent in the study up to T.	Medium6	Dynamic programmingGreedy+2	No attempts yet	10s	512 MB	Judgeable
Let's Solve a Geometry ProblemGiven a fraction p/q, find the smallest base b >= 2 in which p/q has a finite (terminating) expansion.	Medium6	Number theoryMath+2	No attempts yet	2s	512 MB	Judgeable