Problems

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Total results29,445 problems

Coffee Cup Combo
Medium5
Dynamic programming, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
0101
Medium5
Combinatorics, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Logarithm and exponential Taylor polynomials (Small)
Medium5
Math, Dynamic programming
No attempts yet
Time limit
1.5s
Memory limit
512 MB
Judgeable
Earthquake
Medium5
Hash map, String+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Patio
Medium5
String, Prefix sum+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Gomgomi and the Cafeteria
Medium5
Greedy, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Chungchung Visits the Arcade
Medium5
Math, Greedy
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Circus Knight
Medium5
Math, Union-find+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Gomgom and the Tournament
Medium5
Combinatorics, Probability+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Hard Scheduling
Medium5
Simulation, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Perfect Sequence Reverse
Medium5
Implementation, Number theory+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Mathematical Lowest Common Ancestor
Medium5
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tying a Ribbon on a Cat's Neck
Medium5
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Link and Start 2
Medium5
Brute force, Backtracking+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Forbidden Turns
Medium5
Shortest path, Graph+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Data Centers
Medium5
Sorting, Simulation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Alien Invader Yooni
Medium5
Sorting, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Two Roads
Medium5
Shortest path, Graph
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Crystal Crosswind
Medium5
Implementation, Simulation
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Splitstream
Medium5
Recursion, Simulation+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Eating Apples Quickly
Medium5
Backtracking, Brute force
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Brothers in Arms
Medium5
Shortest path, Graph
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Bottle Flip
Medium5
Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Interview Question
Medium5
Number theory, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Justice Served
Medium5
Sorting, Dynamic programming
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Deforestation
Medium5
Greedy, Tree+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Denormalization
Medium5
Math, Number theory+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Skills in Pills
Medium5
Greedy, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Permutations
Medium5
Array, Binary search+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Cutting with Lasers
Medium5
BFS, Matrix+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Eliminating Balloons
Medium5
Greedy, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Geometry of Triangles
Medium5
Dynamic programming, Tree+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Helping the Transit
Medium5
Graph, DFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Production System Management
Medium5
Dynamic programming, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Inspection
Medium5
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Guess the modulo
Medium5
Number theory, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Carts
Medium5
Sorting, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
School informatics
Medium5
Math, Brute force+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Chairs
Medium5
Sorting, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Virus
Medium5
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Writing the Score
Medium5
Dynamic programming, Sliding window
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Easy Assembly
Medium5
Hash map, Implementation+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Brutal Pub
Medium5
Dynamic programming, Probability
No attempts yet
Time limit
9s
Memory limit
1024 MB
Judgeable
Circular Circus
Medium5
Implementation, Array+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lethargic Lumen
Medium5
Graph, Tree+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Heximal
Medium5
Math, String
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Fujiyama Thursday
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Dirty Plates
Medium5
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fixing Traffic
Medium5
Graph, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Jumping Frog
Medium5
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Knights Airways
Medium5
Topological sort, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Spaces, the Final Frontier
Medium5
Dynamic programming, Hash map+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Adrian
Medium5
Prefix sum, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Chocolates
Medium5
Greedy, Prefix sum+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Prijateljice
Medium5
Game theory, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Image Labeler
Medium5
Sorting, Greedy+1
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Maximum Gain
Medium5
Array, Prefix sum
No attempts yet
Time limit
30s
Memory limit
1024 MB
Judgeable
Touchbar Typing
Medium5
Dynamic programming, Array
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Matching Palindrome
Medium5
String, Number theory
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Happy Subarrays
Medium5
Prefix sum, Array+1
No attempts yet
Time limit
25s
Memory limit
1024 MB
Judgeable
Running in Circles
Medium5
Simulation, Math
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Electricity
Medium5
Tree, Dynamic programming+1
No attempts yet
Time limit
40s
Memory limit
1024 MB
Judgeable
Spiral Footrace
Medium5
Simulation, Geometry
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Calculation of Expressions
Medium5
Recursion, String+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Board Arrangements for Concentration Games
Medium5
Backtracking, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Pizza delivery
Medium5
Greedy, Sorting
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
#include
Medium5
Graph, DFS+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
(N+1)-legged race
Medium5
Sorting, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
SubsetCheating
Medium5
Math, Combinatorics
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
NiceSet
Medium5
Sorting, Sliding window+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Uniform and Normal Distributions
Medium5
Probability, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bingo
Medium5
Math, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Square Pen
Medium5
Matrix, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Seed Purchasing
Medium5
Dynamic programming, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Semiperfect
Medium5
Dynamic programming, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Repeat
Medium5
String, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Pegs
Medium5
Backtracking, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
God of Battle
Medium5
Greedy, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
map, filter
Medium5
Array, Hash map+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Find the permutation
Medium5
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Shiroko and the Bank Robbery
Medium5
Dynamic programming, Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Polish Language
Medium5
String, Sliding window+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
New Contract
Medium5
Greedy, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Gramfan
Medium5
Two pointers, Sliding window+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Regular Polygon and Circle
Medium5
Geometry, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Diagnostic 0 : 1
Medium5
Dynamic programming, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Power Plants and Factories
Medium5
Prefix sum, Array
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Delivery Vans
Medium5
Hash map, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Oranżada
Medium5
Greedy, Hash map+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ornitolog 2
Medium5
Dynamic programming, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Agar.io
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Lollipop
Medium5
Sliding window, Hash map
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Smallest Sum
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
High-Heeled Flip-Flops
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Antipalindrome
Medium5
String, Sliding window+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Puzzle Pieces
Medium5
Implementation, Matrix+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Fine Optimization
Medium5
Greedy, Sorting
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Alternating Word II
Medium5
Dynamic programming, String
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Strong Numbers
Medium5
Bit manipulation, Prefix sum+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Pool
Medium5
Greedy, Implementation
No attempts yet
Time limit
6s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Coffee Cup ComboGiven a binary string marking which lecture halls have coffee machines, find the most lectures Jonna can stay awake in while carrying at most two cups.	Medium5	Dynamic programmingGreedy	No attempts yet	1s	1024 MB	Judgeable
0101Count the 0/1 fills of an N×M grid where every 2×2 subarray sums to 2, modulo 10^9+7, with N and M up to 10^18.	Medium5	CombinatoricsMath+1	No attempts yet	1s	512 MB	Judgeable
Logarithm and exponential Taylor polynomials (Small)Given a polynomial P(x) with zero constant term and degree at most n, print the Taylor coefficients of ln(1+P(x)) and e^(P(x))-1 modulo 998244353.	Medium5	MathDynamic programming	No attempts yet	1.5s	512 MB	Judgeable
EarthquakeFor each damaged phone number, count the old-list numbers it can match, where each ? hides one digit and each * hides a run of consecutive digits.	Medium5	Hash mapString+1	No attempts yet	3s	1024 MB	Judgeable
PatioCount contiguous substrings of a tile string that form a square patio with a one-tile border of one color and an interior of the other.	Medium5	StringPrefix sum+1	No attempts yet	3s	1024 MB	Judgeable
Gomgomi and the CafeteriaGiven headcounts and meal tickets for three foods plus a cyclic 3-to-1 exchange event, find the maximum number of people that can be fed.	Medium5	GreedyMath+1	No attempts yet	2s	1024 MB	Judgeable
Chungchung Visits the ArcadeGiven an N by N grid of Gomgom, find the fewest button presses (up, down, left, right) that gather all of them into one cell.	Medium5	MathGreedy	No attempts yet	2s	1024 MB	Judgeable
Circus KnightGiven dolphin IDs, find the largest group of dolphins that can reach each other when two dolphins are linked if their IDs share a divisor greater than 1.	Medium5	MathUnion-find+1	No attempts yet	1s	1024 MB	Judgeable
Gomgom and the TournamentGiven 2^K skill scores and the prize for each round, find the expected prize Gomgom (participant 1) wins in a random bracket, modulo 998244353.	Medium5	CombinatoricsProbability+1	No attempts yet	2s	1024 MB	Judgeable
Hard SchedulingApply Q commands that push a task to the front, sort the stack by ID ascending, or reverse it, then print the ID at position k.	Medium5	SimulationSorting+1	No attempts yet	1s	1024 MB	Judgeable
Perfect Sequence ReverseGiven N and M, build a sequence of length N with values from 0 to 2000 that has exactly M contiguous subarrays whose length and sum are both prime.	Medium5	ImplementationNumber theory+1	No attempts yet	1s	1024 MB	Judgeable
Mathematical Lowest Common AncestorGiven vertices a and b in a tree where each x has parent x divided by its smallest prime factor, find the number of their lowest common ancestor.	Medium5	Number theoryMath+1	No attempts yet	1s	1024 MB	Judgeable
Tying a Ribbon on a Cat's NeckGiven N cats and K ribbon kinds with satisfaction values, find the maximum total satisfaction when no two neighboring cats wear the same ribbon.	Medium5	Dynamic programmingArray	No attempts yet	1s	1024 MB	Judgeable
Link and Start 2Given an N by N matrix of pair values, split N people into two non-empty teams to minimize the difference in their team sums.	Medium5	Brute forceBacktracking+1	No attempts yet	2s	512 MB	Judgeable
Forbidden TurnsFind the shortest distance from v to w in a directed graph where the path never takes a forbidden turn (x, y, z) as two consecutive edges.	Medium5	Shortest pathGraph+1	No attempts yet	2s	1024 MB	Judgeable
Data CentersEach service removes m_i machines from the c_i data centers with the most free machines, and the task asks for the final counts in descending order.	Medium5	SortingSimulation	No attempts yet	2s	1024 MB	Judgeable
Alien Invader YooniGiven building heights, each day every tallest building drops by 1; find the total number of lasers fired over D days.	Medium5	SortingGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Two RoadsGiven a directed graph, for each of Q scenarios that add two one-way roads, find the shortest time from home S to office T, or -1 if unreachable.	Medium5	Shortest pathGraph	No attempts yet	3s	1024 MB	Judgeable
Crystal CrosswindGiven the boundary cells seen for each wind direction, output the crystal layouts with the fewest and the most molecules that fit all observations.	Medium5	ImplementationSimulation	No attempts yet	5s	1024 MB	Judgeable
SplitstreamGiven a network of split and merge nodes fed by 1 to m, answer queries for the kth number on any output node.	Medium5	RecursionSimulation+1	No attempts yet	3s	1024 MB	Judgeable
Eating Apples QuicklyOn a 5 x 5 grid, find the fewest moves for a student to eat 3 apples, where each cell becomes an obstacle after the student leaves it. Print -1 if impossible.	Medium5	BacktrackingBrute force	No attempts yet	1s	512 MB	Judgeable
Brothers in ArmsEach city is an edge between its top and bottom symbols. For each query, find the shortest friendship chain length between two cities, or -1 if none exists.	Medium5	Shortest pathGraph	No attempts yet	10s	1024 MB	Judgeable
Bottle FlipGiven a cylinder's height, radius, and the densities of air and water, find the water height that puts the bottle's centre of mass lowest when upright.	Medium5	Math	No attempts yet	1s	1024 MB	Judgeable
Interview QuestionGiven a transcript of consecutive Fizz Buzz outputs, find any values of a and b that could have produced it.	Medium5	Number theoryBrute force+1	No attempts yet	1s	1024 MB	Judgeable
Justice ServedEach suspect is a time interval, and the task is to find for each one the longest chain of alibis from suspects whose stays fully contain it.	Medium5	SortingDynamic programming	No attempts yet	5s	1024 MB	Judgeable
DeforestationGiven a tree of segment weights and a carrying limit W, find the minimum number of pieces needed so that each piece weighs at most W.	Medium5	GreedyTree+1	No attempts yet	2s	1024 MB	Judgeable
DenormalizationGiven a unit vector's coordinates rounded to 12 decimals, recover the integer list (values up to 10000, gcd 1) that produced it.	Medium5	MathNumber theory+1	No attempts yet	5s	1024 MB	Judgeable
Skills in PillsGiven k, j, and n, find the fewest pill days in 1 to n so that pill A appears at least once in every k days, pill B in every j days, and no day has both.	Medium5	GreedyMath	No attempts yet	1s	1024 MB	Judgeable
PermutationsGiven an inversion table of a permutation, output the permutation's cycle notation with each cycle starting from its smallest element.	Medium5	ArrayBinary search+1	No attempts yet	2s	1024 MB	Judgeable
Cutting with LasersGiven a closed path of axis-parallel laser cuts on a sheet, find the area of the largest enclosed piece that does not touch the sheet edge.	Medium5	BFSMatrix+1	No attempts yet	1s	1024 MB	Judgeable
Eliminating BalloonsGiven balloon heights from left to right, find the fewest arrows where each arrow pops balloons at heights H, H-1, H-2, and so on in order.	Medium5	GreedyArray	No attempts yet	1s	1024 MB	Judgeable
Geometry of TrianglesGiven triangles of a triangulated polygon, pick the subset with the least total area so that every side still belongs to a chosen triangle.	Medium5	Dynamic programmingTree+1	No attempts yet	1s	1024 MB	Judgeable
Helping the TransitGiven N reference points and M one-way streets, find the fewest one-way bridges to add so that every point can reach every other point.	Medium5	GraphDFS+1	No attempts yet	1s	1024 MB	Judgeable
Production System ManagementGiven N jobs whose success probability rises with each extra machine, buy machines within budget B to maximize the product of all success probabilities.	Medium5	Dynamic programmingImplementation	No attempts yet	1s	512 MB	Judgeable
InspectionFind the fewest new one-way roads to add so that the towns contain a round trip (directed cycle), or report -1 if impossible.	Medium5	Shortest pathGraph+1	No attempts yet	1s	1024 MB	Judgeable
Guess the moduloGuess the hidden modulus M by querying an interactive judge that returns the sum of the last N array elements modulo M after each appended number.	Medium5	Number theoryImplementation	No attempts yet	1s	1024 MB	Judgeable
CartsFind the fewest unit cart moves needed to line up n carts on integer cells into one contiguous horizontal or vertical segment.	Medium5	SortingGreedy+1	No attempts yet	1s	1024 MB	Judgeable
School informaticsGiven alphabet size N, message length L, and maximum group size K, find the group size B from 1 to K that minimizes the total bits of the space-padded encoded message.	Medium5	MathBrute force+1	No attempts yet	3s	1024 MB	Judgeable
ChairsFind the lexicographically smallest shortest R/D path from the top-left to the bottom-right cell that visits every chair, or report Impossible.	Medium5	SortingDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
VirusFind the smallest set of initially infected cells in an n x m grid so that the two-neighbor spreading rule eventually infects every cell.	Medium5	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Writing the ScoreGiven a sequence of notes and rests, find the fewest pages of at most X symbols where each page except the last ends with K consecutive rests.	Medium5	Dynamic programmingSliding window	No attempts yet	1s	1024 MB	Judgeable
Easy AssemblyGiven towers of distinct numbers, find the fewest split and combine operations needed to stack all blocks into one tower sorted ascending from the top.	Medium5	Hash mapImplementation+1	No attempts yet	3s	1024 MB	Judgeable
Brutal PubGiven each pub's initial dominant votes, find the probability that each pub is chosen when the remaining students vote in proportion to current counts.	Medium5	Dynamic programmingProbability	No attempts yet	9s	1024 MB	Judgeable
Circular CircusFrom each rotation's count of northernmost changes and the final northernmost letter, rebuild the circular seating order or report inconsistency.	Medium5	ImplementationArray+1	No attempts yet	1s	1024 MB	Judgeable
Lethargic LumenGiven an acyclic undirected graph with n nodes, add edges to make it a tree and print the smallest possible diameter.	Medium5	GraphTree+2	No attempts yet	1s	1024 MB	Judgeable
HeximalGiven a decimal integer N with up to 500000 digits, output how many digits its base-6 representation has.	Medium5	MathString	No attempts yet	5s	1024 MB	Judgeable
Fujiyama ThursdayAssign four diners to each car, given arrival times and eating speeds, so that the last person finishes eating as early as possible.	Medium5	GreedySorting	No attempts yet	1s	1024 MB	Judgeable
Dirty PlatesGiven counts of clean-on-both-sides, clean-on-one-side, and dirty-on-both-sides plates, find the maximum meals Louie can eat before he must clean.	Medium5	MathGreedy	No attempts yet	1s	1024 MB	Judgeable
Fixing TrafficGiven a directed street network, find the street whose unlimited widening raises the max flow from intersection 0 to m-1 the most, and report the gain.	Medium5	GraphBrute force	No attempts yet	1s	1024 MB	Judgeable
Jumping FrogGiven a start point and a target point, decide whether repeated jumps of the form (x+y, y), (x-y, y), (x, y+x), or (x, y-x) can connect them.	Medium5	Number theoryMath	No attempts yet	1s	1024 MB	Judgeable
Knights AirwaysGiven flight schedules, order the flights so each arrival into a city comes before departures from that city, picking the smallest flight numbers first.	Medium5	Topological sortGraph+1	No attempts yet	1s	1024 MB	Judgeable
Spaces, the Final FrontierSplit a string with no spaces into dictionary words so the sum of their values is maximized, breaking ties by the earliest space.	Medium5	Dynamic programmingHash map+1	No attempts yet	1s	1024 MB	Judgeable
AdrianCount the substrings of a lowercase word whose letters can be rearranged into a palindrome.	Medium5	Prefix sumBit manipulation+1	No attempts yet	1s	1024 MB	Judgeable
ChocolatesFor each query, pick m chocolates to minimize Lana's payment minus Fran's payment, where Fran pays only the part of each price above k.	Medium5	GreedyPrefix sum+2	No attempts yet	1s	1024 MB	Judgeable
PrijateljiceTwo players alternately say larger words from their own sorted lists, starting with the same or next letter. Decide the winner if Leona opens with her smallest word.	Medium5	Game theoryDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Image LabelerSplit N regions into M non-empty categories to maximize the sum of each category's median participant count.	Medium5	SortingGreedy+1	No attempts yet	Not set	1024 MB	Judgeable
Maximum GainGiven two arrays and K, take K points total by removing elements from either end of each array to maximize the sum.	Medium5	ArrayPrefix sum	No attempts yet	30s	1024 MB	Judgeable
Touchbar TypingGiven a word S and a one-row keyboard K, find the minimum finger movement time to type every character of S in order.	Medium5	Dynamic programmingArray	No attempts yet	Not set	1024 MB	Judgeable
Matching PalindromeGiven a palindrome P, find the shortest non-empty palindrome Q such that the concatenation PQ is also a palindrome.	Medium5	StringNumber theory	No attempts yet	Not set	1024 MB	Judgeable
Happy SubarraysGiven an array A, find the sum of the values of all subarrays whose every prefix sum is non-negative.	Medium5	Prefix sumArray+1	No attempts yet	25s	1024 MB	Judgeable
Running in CirclesGiven a circular track of length L and a series of runs with distances and directions, count the laps the machine records for Ada.	Medium5	SimulationMath	No attempts yet	Not set	1024 MB	Judgeable
ElectricityGiven a tree where power flows only to neighbors with strictly lower capacity, find the most junctions one powered junction can reach.	Medium5	TreeDynamic programming+1	No attempts yet	40s	1024 MB	Judgeable
Spiral FootraceStarting at the origin facing north, each runner visits the unvisited flag at the smallest clockwise angle from its heading. Find the total course length.	Medium5	SimulationGeometry	No attempts yet	1s	1024 MB	Judgeable
Calculation of ExpressionsEvaluates expressions with +, -, * and parentheses over complex integers, printing overflow when any step has a part beyond ±10000.	Medium5	RecursionString+1	No attempts yet	1s	1024 MB	Judgeable
Board Arrangements for Concentration GamesCount the perfect pairings of a 4x4 grid where each pair of cells differs by one of four given offsets, treating swapped labelings as the same pattern.	Medium5	BacktrackingBrute force	No attempts yet	1s	1024 MB	Judgeable
Pizza deliveryGiven N customers with delivery times t_i and irritability a_i, find the single-courier delivery order that minimizes total stress.	Medium5	GreedySorting	No attempts yet	2s	1024 MB	Judgeable
#includeGiven a directed include graph, find the smallest set of files whose direct inclusion covers all files, breaking ties by the smallest sum of file numbers.	Medium5	GraphDFS+1	No attempts yet	2s	1024 MB	Judgeable
(N+1)-legged racePick N students and an order so that the sum of their abilities minus the total height gaps between neighbors is as large as possible.	Medium5	SortingDynamic programming+1	No attempts yet	2s	1024 MB	Judgeable
SubsetCheatingCount the score assignments over N problems where Little Triangle's score is at most Little Square's on each problem, with totals A and B, modulo 1e9+7.	Medium5	MathCombinatorics	No attempts yet	1s	1024 MB	Judgeable
NiceSetGiven n integers and a bound S, find the size of the largest subset whose pairwise absolute differences sum to at most S.	Medium5	SortingSliding window+1	No attempts yet	1s	1024 MB	Judgeable
Uniform and Normal DistributionsGiven 5000 samples in [0, 1], decide whether each came from U(0, 1) or from N(0.5, 0.1) truncated to [0, 1].	Medium5	ProbabilityMath+1	No attempts yet	1s	1024 MB	Judgeable
BingoGiven a partly colored n by n bingo board and k more random calls, find the expected number of fully colored lines, scaled by (n^2)! modulo 1e9+7.	Medium5	MathCombinatorics+2	No attempts yet	1s	1024 MB	Judgeable
Square PenGiven a grid of free cells and obstacles, find the area of the largest all-free square subgrid.	Medium5	MatrixDynamic programming	No attempts yet	1s	1024 MB	Judgeable
Seed PurchasingGiven seed bags with a cost, crop count, and crop price, find the most money you can earn from crops within a fixed seed budget.	Medium5	Dynamic programmingImplementation	No attempts yet	1s	1024 MB	Judgeable
SemiperfectFor each integer m below 1,000,000, decide whether some subset of its proper divisors sums to m.	Medium5	Dynamic programmingMath+1	No attempts yet	1s	1024 MB	Judgeable
RepeatFor each string, find the longest substring that appears twice without overlapping, and print its length and the earliest such substring.	Medium5	StringDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
PegsGiven a peg solitaire board, decide whether a sequence of hops can leave exactly one peg on the board.	Medium5	BacktrackingBrute force+1	No attempts yet	1s	1024 MB	Judgeable
God of BattleGiven a budget N and two mercenary types with power A and B and costs PA and PB, find the counts x and y that maximize Ax+By within the budget.	Medium5	GreedyBrute force+1	No attempts yet	1s	1024 MB	Judgeable
map, filterApply a sequence of map and filter commands to an array of N integers and print the size of the array after each filter.	Medium5	ArrayHash map+1	No attempts yet	1s	1024 MB	Judgeable
Find the permutationGiven array B, built by XORing the sorted prefixes of a permutation P together with P, the task is to recover P.	Medium5	ImplementationSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Shiroko and the Bank RobberyPick k of n applicants, where each pair of values sums to x, to maximize the product of the total a and the total b.	Medium5	Dynamic programmingMath	No attempts yet	1s	512 MB	Judgeable
Polish LanguageCount the substrings of a lowercase string that contain three consecutive consonants or three consecutive vowels, counting each position separately.	Medium5	StringSliding window+1	No attempts yet	1s	1024 MB	Judgeable
New ContractGiven N integers, find the fewest total digits to append to them so that the resulting sequence is strictly increasing.	Medium5	GreedyMath	No attempts yet	2s	1024 MB	Judgeable
GramfanCount the substrings of S that contain all 26 letters, with the letters in non-decreasing alphabetical order.	Medium5	Two pointersSliding window+1	No attempts yet	1s	1024 MB	Judgeable
Regular Polygon and CircleGiven a regular N-gon with area A and a circle with area B, find the most polygon vertices that can fit inside the circle or on its edge.	Medium5	GeometryMath+1	No attempts yet	1s	1024 MB	Judgeable
Diagnostic 0 : 1Count integers k in [a, b] whose base-m digit sum equals n, for up to 50,000 test cases.	Medium5	Dynamic programmingMath	No attempts yet	2s	1024 MB	Judgeable
Power Plants and FactoriesConnect power plants and factories placed on a line of n cities with adjacent grid segments, minimizing total segment length so every factory gets its demand.	Medium5	Prefix sumArray	No attempts yet	2s	1024 MB	Judgeable
Delivery VansGiven delivery vans that leave garages on avenues or streets, find the fewest vans to cancel so no two remaining vans share an intersection at the same moment.	Medium5	Hash mapMath	No attempts yet	2s	1024 MB	Judgeable
OranżadaGiven n bottles in a row, find the fewest adjacent swaps that make the first k bottles all have different brands, or report -1 if impossible.	Medium5	GreedyHash map+1	No attempts yet	1s	1024 MB	Judgeable
Ornitolog 2Given a sequence of pitches, find the fewest notes to replace so that the pitches strictly alternate between rising and falling.	Medium5	Dynamic programmingImplementation	No attempts yet	1s	1024 MB	Judgeable
Agar.ioFind the fewest absorptions for a cell starting at mass 2 to reach or match the largest opponent mass, absorbing only cells smaller than itself.	Medium5	GreedySorting+1	No attempts yet	1.5s	1024 MB	Judgeable
LollipopFind the shortest contiguous piece in which some flavor appears at least three times, or report NIE if no such piece exists.	Medium5	Sliding windowHash map	No attempts yet	4s	1024 MB	Judgeable
Smallest SumGiven digit tiles, build exactly K positive integers without leading zeros so that their total sum is as small as possible.	Medium5	GreedySorting+1	No attempts yet	0.5s	1024 MB	Judgeable
High-Heeled Flip-FlopsGiven people's heights and flip-flop heel heights, find the maximum number of people who can reach height T, with each person wearing at most one pair.	Medium5	GreedySorting+1	No attempts yet	2s	1024 MB	Judgeable
AntipalindromeCount the contiguous substrings of the given word that contain no palindrome of length 2 or more.	Medium5	StringSliding window+1	No attempts yet	1s	1024 MB	Judgeable
Puzzle PiecesDecide whether two pieces, each cut from a rectangle by one straight cut, can be rotated or flipped to fit together without overlap.	Medium5	ImplementationMatrix+1	No attempts yet	5s	1024 MB	Judgeable
Fine OptimizationPair each speed value K with one service number R so that the sum of the concatenated digit strings is as small as possible, then print that minimum.	Medium5	GreedySorting	No attempts yet	10s	1024 MB	Judgeable
Alternating Word IICount the length-3 subsequences whose adjacent letters differ, and count the distinct three-letter alternating words they spell.	Medium5	Dynamic programmingString	No attempts yet	8s	1024 MB	Judgeable
Strong NumbersFor each query interval [A, B] with B up to 10^13, sum every number that is a sum of distinct factorials inside that interval.	Medium5	Bit manipulationPrefix sum+2	No attempts yet	1s	1024 MB	Judgeable
PoolGiven N distance readings from the shore, find the minimum number of pool lengths Bajtek must have swum to produce them.	Medium5	GreedyImplementation	No attempts yet	6s	1024 MB	Judgeable