Problems

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Total results29,445 problems

Tournament Seeding
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Photoshoot 2
Medium5
Array, Greedy+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Clean Up!
Medium5
String, Tree+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Trans
Medium5
Bit manipulation, Divide and conquer
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Dijamant
Medium5
Matrix, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Introduction to Calculus 2
Medium5
Math, Geometry
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Severe Staircase Addiction
Medium5
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
GGG
Medium5
Math, Combinatorics
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Pawn Shop
Medium5
Hash map, Greedy
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Protect the Pollen!
Medium5
Tree, Dynamic programming
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
RSA Mistake
Medium5
Math, Number theory
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Slide Count
Medium5
Two pointers, Sliding window+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cracking The Safe
Medium5
Matrix, Brute force+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
First Orchard
Medium5
Probability, Dynamic programming
No attempts yet
Time limit
6s
Memory limit
1024 MB
Judgeable
Robot Turtles
Medium5
BFS, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Through the Grapevine
Medium5
Graph, BFS+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Traveling Monk
Medium5
Binary search, Simulation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Criss-Cross
Medium5
Geometry, Hash map+1
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Pharmacy
Medium5
Simulation, Heap+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Bar Code
Medium5
Backtracking, Implementation
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Field Trip
Medium5
Prefix sum, Binary search
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
I.O.U.
Medium5
Graph, DFS
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Perfect Skyline
Medium5
Bit manipulation, Dynamic programming+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Annoyed Coworkers
Medium5
Binary search, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Jack The Lumberjack
Medium5
Sorting, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Random Digital Exponentiation
Medium5
Backtracking, Number theory
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Counting Codes
Medium5
Backtracking, Matrix+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Air Conditioner
Medium5
Intervals, Greedy
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Third Group Exam
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Work or Sleep!
Medium5
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Fair Robbery
Medium5
Array, Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Numbers
Medium5
Brute force, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Good Colorings
Medium5
Backtracking, Brute force+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Campfire Firewood
Medium5
Simulation, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Word Magic Square
Medium5
Backtracking, Hash map+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Split the SSHS
Medium5
Hash map, Tree+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Inversions Organize
Medium5
Math, Matrix+1
No attempts yet
Time limit
20s
Memory limit
1024 MB
Judgeable
Ordinary Ordinals
Medium5
Math, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Problematic Polygons
Medium5
Geometry, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Distributing Kits
Medium5
Prefix sum, Array+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
줄넘기
Medium5
Hash map, Sorting+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Lottery Fun Time
Medium5
Hash map, Brute force+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Visits
Medium5
Graph, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Most Ordered Way
Medium5
Greedy, Sorting
No attempts yet
Time limit
0.3s
Memory limit
1024 MB
Judgeable
Well Off
Medium5
Graph, DFS
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Icing
Medium5
Graph, BFS+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Polynomial Evaluation
Medium5
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Product of a Self-Describing Sequence
Medium5
Math, Simulation
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
convex4gon
Medium5
Geometry, Combinatorics+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
ALSDJFKSND
Medium5
Game theory, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
biinfinite
Medium5
Dynamic programming, Matrix
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
LAN Cable Connection
Medium5
Dynamic programming, Math
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Best Edge
Medium5
Shortest path, Graph+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Evolution of Weasels
Medium5
String, Greedy
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Boundary
Medium5
Number theory, Brute force
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Longest straight from dice
Medium5
Greedy, Sorting
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Single-track railway
Medium5
Segment tree, Prefix sum+1
No attempts yet
Time limit
4s
Memory limit
512 MB
Judgeable
Ontongdaejeon
Medium5
Greedy, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Subarray Score Sum
Medium5
Sliding window, Hash map+1
No attempts yet
Time limit
1.5s
Memory limit
512 MB
Judgeable
Letter Blocks
Medium5
Greedy, String+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Crispy Pastries
Medium5
Segment tree, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Even Stronger
Medium5
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
KLIZA
Medium5
BFS, Graph
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Kryptonite
Medium5
Dynamic programming, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lazy Ari's Vaccination Schedule
Medium5
Topological sort, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ari's Cheerful Outing
Medium5
Dynamic programming, Matrix
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Meticulous Kuki's Graduation Trip
Medium5
Graph, Union-find
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Clean Water of Mount Piat
Medium5
Sorting, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Gomgomi's Errand
Medium5
Tree, BFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Shakashaka
Medium5
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Gahee and the Jungbu Naeryuk Line
Medium5
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Gahui and the Video Recommendation System
Medium5
Sliding window, Hash map+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Monty's Hall
Medium5
Probability, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Efficient Bus Routing
Medium5
Tree, Greedy+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Bar Classification
Medium5
Matrix, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Marathon
Medium5
Binary search, Probability
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Bike Party
Medium5
Prefix sum, Array+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Longest Arithmetic Subsequence
Medium5
Dynamic programming, Array
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Sprouts
Medium5
Sliding window, Prefix sum+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Scenery 2
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Siru's Department Store Tour
Medium5
BFS, Matrix+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
K Primes
Medium5
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
200% Mixed Juice!
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
SHOW ME THE DUNGEON
Medium5
Dynamic programming, Sorting+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Drop 7
Medium5
Simulation, Brute force
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Cutting the Long Cake
Medium5
Combinatorics, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Inversion Parity and Queries
Medium5
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Artificial Neural Network
Medium5
Math, Array
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Maximum LCM
Medium5
Math, Number theory
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ball Draw Guessing Game
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Deletive Editing
Medium5
String, Implementation
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Heroes of Might
Medium5
Greedy, Heap+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Cramming
Medium5
Math, Binary search+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Strange Switches
Medium5
BFS, Bit manipulation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Club federation tournament for the national university programming contest
Medium5
Tree, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Level Up
Medium5
Sorting, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Abracadabra
Medium5
Array, Simulation+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Chalk Thief
Medium5
Union-find, Sorting+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
No-Edge Pizza
Medium5
Hash map, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Stimulant
Medium5
Prefix sum, Sorting+1
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Tournament SeedingGiven 2^n player ratings and a threshold k, find the maximum number of close games in a seeded single-elimination bracket where higher ratings always win.	Medium5	GreedySorting	No attempts yet	1s	1024 MB	Judgeable
Photoshoot 2Given a start permutation and a target permutation, count the fewest cows you must move left (one at a time) to reach the target order.	Medium5	ArrayGreedy+2	No attempts yet	2s	1024 MB	Judgeable
Clean Up!Given n file names and a limit k, find the fewest rm commands of the form prefix* that delete all files, where each command deletes at most k files.	Medium5	StringTree+1	No attempts yet	2s	512 MB	Judgeable
TransGiven an array a of 2^n integers, compute for each i the sum of a_j over all j where popcount(i and j) is odd.	Medium5	Bit manipulationDivide and conquer	No attempts yet	2s	512 MB	Judgeable
DijamantCount the diamonds in an n by m table of '.' and '#' characters, where each diamond has a border of '#' and an interior of only '.'.	Medium5	MatrixDynamic programming+1	No attempts yet	1s	512 MB	Judgeable
Introduction to Calculus 2Given a first-quadrant triangle, print the volumes of the solids formed by rotating it about the x-axis and the y-axis.	Medium5	MathGeometry	No attempts yet	1s	1024 MB	Judgeable
Severe Staircase AddictionGiven N values, decide whether they can be ordered in a cycle where every adjacent pair, including the last and first, differs by exactly 1.	Medium5	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
GGGGiven the coefficients of a polynomial modulo 1e9+7, write the sequence f(0), f(1), f(2), ... in GGG notation using the fewest values.	Medium5	MathCombinatorics	No attempts yet	1s	1024 MB	Judgeable
Pawn ShopSplit the rearranged sequence b into as many consecutive groups as possible so that each group holds the same multiset of values as the same positions in a.	Medium5	Hash mapGreedy	No attempts yet	2s	1024 MB	Judgeable
Protect the Pollen!Choose flower families so that no two adjacent flowers in the tree are both chosen, with at most S bees total, maximizing total pollination power.	Medium5	TreeDynamic programming	No attempts yet	5s	1024 MB	Judgeable
RSA MistakeGiven A and B, output full credit if they are distinct primes, partial credit if A*B has no square factor k^2 with k at least 2, otherwise no credit.	Medium5	MathNumber theory	No attempts yet	1s	1024 MB	Judgeable
Slide CountGiven an array and a constant C, count for each element how many distinct windows produced by a two-pointer scan contain it.	Medium5	Two pointersSliding window+1	No attempts yet	1s	1024 MB	Judgeable
Cracking The SafeFind the fewest presses that turn a 3x3 grid of digits 0 to 3 into all zeros, where a press adds 1 mod 4 to its row and column, or report -1.	Medium5	MatrixBrute force+1	No attempts yet	3s	1024 MB	Judgeable
First OrchardGiven the fruit counts on four trees and the raven's path length, compute the probability that players pick every fruit before the raven reaches the orchard.	Medium5	ProbabilityDynamic programming	No attempts yet	6s	1024 MB	Judgeable
Robot TurtlesFind the shortest F, R, L, X program that moves the turtle from the bottom-left corner to the diamond on an 8x8 board with rock and ice castles.	Medium5	BFSSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Through the GrapevineCount how many people besides the source hear a rumor within d days, when each person must hear it from a set number of distinct contacts first.	Medium5	GraphBFS+1	No attempts yet	4s	1024 MB	Judgeable
Traveling MonkGiven the monk's ascent and descent segments on the same path, find the earliest time both trips put him at the same elevation.	Medium5	Binary searchSimulation	No attempts yet	2s	1024 MB	Judgeable
Criss-CrossCount the distinct points where any two of up to 1000 given line segments intersect or touch, ignoring pairs that overlap along a line.	Medium5	GeometryHash map+1	No attempts yet	10s	1024 MB	Judgeable
PharmacySimulate T technicians filling prescriptions where in-store orders go before remote ones, and output the average completion time for each type.	Medium5	SimulationHeap+1	No attempts yet	3s	1024 MB	Judgeable
Bar CodeGiven the group counts for each row and column, place non-touching bars on the n by n grid borders so every line matches its specification.	Medium5	BacktrackingImplementation	No attempts yet	10s	1024 MB	Judgeable
Field TripSplit class sections 1 to N into three contiguous groups so that no teacher rides a bus, printing the split points i and j or -1 if impossible.	Medium5	Prefix sumBinary search	No attempts yet	3s	1024 MB	Judgeable
I.O.U.Given a list of I.O.U. debts between friends, cancel every debt cycle by its minimum amount and output the debts that remain.	Medium5	GraphDFS	No attempts yet	3s	1024 MB	Judgeable
Perfect SkylineGiven N block heights and S target heights, find disjoint subsets of blocks whose sums equal each target, or report that no assignment exists.	Medium5	Bit manipulationDynamic programming+1	No attempts yet	4s	1024 MB	Judgeable
Annoyed CoworkersGiven h help requests and coworkers whose annoyance starts at a and rises by d per ask, find the minimum possible maximum annoyance across all coworkers.	Medium5	Binary searchMath+1	No attempts yet	2s	1024 MB	Judgeable
Jack The LumberjackGiven N tree species that are planted, grow linearly for Y years, then shrink, find the maximum total number of trees alive in any single year.	Medium5	SortingSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Random Digital ExponentiationGiven plaintext a and ciphertext b, find the exponent applied to each digit of a so that the digit powers placed at their place values sum to b.	Medium5	BacktrackingNumber theory	No attempts yet	1s	1024 MB	Judgeable
Counting CodesCount the ways to fill the zeros in a partial m by n grid so each row has distinct digits and every L-shaped triple obeys the arithmetic rule.	Medium5	BacktrackingMatrix+1	No attempts yet	5s	1024 MB	Judgeable
Air ConditionerDecide whether an air conditioner that can heat, cool, or stay off, starting at temperature m, keeps every customer's temperature at visit time within their range.	Medium5	IntervalsGreedy	No attempts yet	1s	256 MB	Judgeable
Third Group ExamGiven per-block theory grades x_i and practice grades y_i, pick at least a theory blocks and at least b practice blocks to maximize the total grade, and print the choice.	Medium5	GreedySorting	No attempts yet	1s	512 MB	Judgeable
Work or Sleep!Given the performance X% at T/6 sleep hours and a day of T hours, find the maximum of (awake hours times performance) over all sleep times.	Medium5	MathImplementation	No attempts yet	1s	512 MB	Judgeable
Fair RobberyFor each k, choose a fraction t of every house from k to n to minimize the resulting richest-minus-poorest gap, breaking ties by stealing more.	Medium5	ArrayMath	No attempts yet	1s	512 MB	Judgeable
NumbersGiven x and a mood flag, find the smallest y at least x whose digits are all equal, or all equal except one digit when the flag is 1.	Medium5	Brute forceImplementation+1	No attempts yet	1s	512 MB	Judgeable
Good ColoringsGiven an n by m grid and c colors (n, m up to 10, c up to 3), color every cell so no axis-parallel rectangle has all four corners in one color.	Medium5	BacktrackingBrute force+1	No attempts yet	1s	512 MB	Judgeable
Campfire FirewoodCount the ways SKH can move or stay and add firewood each hour so that at least K of the N bonfires remain lit until the session ends.	Medium5	SimulationDynamic programming+1	No attempts yet	2s	1024 MB	Judgeable
Word Magic SquarePick L of the N given words to form an L by L square whose rows and columns read the same, choosing the smallest dictionary order, or print NONE.	Medium5	BacktrackingHash map+1	No attempts yet	2s	1024 MB	Judgeable
Split the SSHSGiven a tree with colored edges, repaint one edge at a time and report how many same-color connected pieces the tree splits into after each repaint.	Medium5	Hash mapTree+1	No attempts yet	1s	512 MB	Judgeable
Inversions OrganizeGiven a 2N by 2N grid of I and O letters, find the fewest cell flips so the top and bottom halves have equal I counts and the left and right halves do too.	Medium5	MathMatrix+1	No attempts yet	20s	1024 MB	Judgeable
Ordinary OrdinalsGiven N and M, find how many brace and comma characters write the set representation of N, modulo M, for N below 2^63.	Medium5	MathDynamic programming	No attempts yet	1s	1024 MB	Judgeable
Problematic PolygonsFor each integer angle from 0 to 359, rotate a simple polygon around the origin and find the smallest angle where it fits inside a second simple polygon, or report impossible.	Medium5	GeometryBrute force+1	No attempts yet	1s	1024 MB	Judgeable
Distributing KitsGiven N rooms holding A_i kits each, find the fewest single-kit passes between adjacent rooms needed to make every room hold the average count.	Medium5	Prefix sumArray+1	No attempts yet	1s	256 MB	Judgeable
줄넘기For each query range [l, r], find the longest segment whose two ends have equal heights and no student in between has that same height, or print 0.	Medium5	Hash mapSorting+1	No attempts yet	2s	256 MB	Judgeable
Lottery Fun TimePick one first prize ticket, one four-digit second prize suffix, and up to three two-digit third prize suffixes to maximize total winnings.	Medium5	Hash mapBrute force+1	No attempts yet	2s	1024 MB	Judgeable
VisitsEach buddy i wants to visit a_i and gets v_i moos for a visit. Find the maximum total moos over all visiting orders p.	Medium5	GraphImplementation	No attempts yet	2s	1024 MB	Judgeable
Most Ordered WayOrder N tasks with times T and deadlines D so each finishes on time, choosing the lexicographically smallest order, or print * if impossible.	Medium5	GreedySorting	No attempts yet	0.3s	1024 MB	Judgeable
Well OffGiven pairwise inequalities of the form plus or minus x_i plus or minus x_j greater than 0, decide whether some assignment of fortunes satisfies all of them.	Medium5	GraphDFS	No attempts yet	2s	128 MB	Judgeable
IcingGiven battle records as edges, count the smallest sets of at most two edges whose deletion makes the graph bipartite, or return 0 if none exists.	Medium5	GraphBFS+1	No attempts yet	3s	1024 MB	Judgeable
Polynomial EvaluationGiven a polynomial of degree N and a prime P, print f(x) mod P for every x from 0 to P-1.	Medium5	Number theoryMath+1	No attempts yet	1s	1024 MB	Judgeable
Product of a Self-Describing SequenceGiven n up to 10^12, compute the product of the first n terms of the self-describing sequence G modulo 1,000,000,007.	Medium5	MathSimulation	No attempts yet	0.5s	1024 MB	Judgeable
convex4gonGiven n points with no three collinear, count the convex quadrilaterals that can be formed from four of them.	Medium5	GeometryCombinatorics+1	No attempts yet	2s	1024 MB	Judgeable
ALSDJFKSNDGiven the ball's distance x, speed v, and acceleration a, decide whether Alice wins under optimal play with her first move A, with B, with either, or with neither.	Medium5	Game theoryMath+1	No attempts yet	2s	1024 MB	Judgeable
biinfiniteGiven t and n, return floor(K_n) mod M (M = 202112210950) for the KSA bi-infinite sequence with parameter t, where n can be negative.	Medium5	Dynamic programmingMatrix	No attempts yet	2s	1024 MB	Judgeable
LAN Cable ConnectionChoose a nonempty set of switches with minimum total cost so their ports exactly fit M computers plus one uplink cable, or report -1 if impossible.	Medium5	Dynamic programmingMath	No attempts yet	1.5s	1024 MB	Judgeable
Best EdgeGiven a directed weighted graph with unique shortest paths, find the edges that lie on the most shortest paths between vertex pairs and print their numbers.	Medium5	Shortest pathGraph+2	No attempts yet	2s	1024 MB	Judgeable
Evolution of WeaselsGiven two DNA strings over A, B, and C, decide whether inserting or deleting AA, BB, CC, ABAB, or BCBC can turn one into the other.	Medium5	StringGreedy	No attempts yet	2s	2048 MB	Judgeable
BoundaryGiven a w by l bathroom, find every tile length a for which 1 by a boundary tiles and 1 by 1 interior tiles exactly cover the floor.	Medium5	Number theoryBrute force	No attempts yet	2s	2048 MB	Judgeable
Longest straight from diceGiven dice with S_i sides each, find the most dice that can each show one number in a run of consecutive integers.	Medium5	GreedySorting	No attempts yet	Not set	1024 MB	Judgeable
Single-track railwayAfter each change to a section's travel time, find the station where the two trains' waiting time is smallest and print that minimum.	Medium5	Segment treePrefix sum+1	No attempts yet	4s	512 MB	Judgeable
OntongdaejeonGiven N item prices in order, find the minimum cash needed when each cash payment earns 10 percent cashback that can offset later prices.	Medium5	GreedyMath	No attempts yet	1s	1024 MB	Judgeable
Subarray Score SumFor each test case, sum i^len + j^len over every subarray A[i, j] of length 2 or more with all distinct values, modulo 1e9+7.	Medium5	Sliding windowHash map+1	No attempts yet	1.5s	512 MB	Judgeable
Letter BlocksGiven several towers of letter blocks, stack them all into one megatower where each letter forms a single contiguous group, or report IMPOSSIBLE.	Medium5	GreedyString+1	No attempts yet	5s	1024 MB	Judgeable
Crispy PastriesProcess add, eat, and serve operations on plates of cakes, and report how many plates each serve removes (plates with at least y cakes).	Medium5	Segment treeImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Even StrongerPick which villages to recruit at minimum gold so that the towers' archers can hit at least k soldiers along the path.	Medium5	Dynamic programming	No attempts yet	1s	1024 MB	Judgeable
KLIZAGiven a 3x3 sliding puzzle, find the fewest moves to reach the solved grid and print the tile moved into the blank cell at each step.	Medium5	BFSGraph	No attempts yet	1s	1024 MB	Judgeable
KryptoniteFind a down/right path from the top-left to the bottom or right edge minimizing the sum of Chebyshev-distance-K neighborhood weights at each visited cell.	Medium5	Dynamic programmingPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Lazy Ari's Vaccination ScheduleGiven N vaccines with prerequisite pairs and minimum waiting periods, find the fewest total days needed to give all vaccines.	Medium5	Topological sortDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Ari's Cheerful OutingFind the most tasks Ari can finish along a right, down, or diagonal grid path from corner to corner within T minutes.	Medium5	Dynamic programmingMatrix	No attempts yet	1s	1024 MB	Judgeable
Meticulous Kuki's Graduation TripAfter each sight is removed in order, determine whether the remaining graph is still connected, checking the initial graph too.	Medium5	GraphUnion-find	No attempts yet	2s	512 MB	Judgeable
Clean Water of Mount PiatChoose the most hikers who can drink in some order, each with a threshold above the contamination at their turn, and minimize the final level.	Medium5	SortingDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Gomgomi's ErrandGiven a tree and the route S to C to H, count the ordered pairs of distinct cities where Gomgomi can buy two chicken legs in order.	Medium5	TreeBFS+1	No attempts yet	1s	1024 MB	Judgeable
ShakashakaGiven a filled Shakashaka board, check whether every white region is a rectangle and each numbered black square touches exactly its number of triangles.	Medium5	ImplementationSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Gahee and the Jungbu Naeryuk LineSimulate down and up trains on a single-track line with station stops and section permissions, then print each train's arrival time at its final station.	Medium5	SimulationImplementation	No attempts yet	1s	512 MB	Judgeable
Gahui and the Video Recommendation SystemFor each R event, print the id of the video with the highest relevance score, where the score is its watch count plus its category's watch count over the past 72 hours.	Medium5	Sliding windowHash map+2	No attempts yet	5s	512 MB	Judgeable
Monty's HallPick s of d doors, let Monty open e empty doors, then pick s doors again; find the maximum probability of winning.	Medium5	ProbabilityMath+1	No attempts yet	1s	1024 MB	Judgeable
Efficient Bus RoutingGiven a tree of N cities, cover every road with the fewest bus paths and print the two end stops of each path.	Medium5	TreeGreedy+1	No attempts yet	5s	1024 MB	Judgeable
Bar ClassificationGiven an N by N binary grid built from one all-ones row or column with up to N flipped cells, decide whether the bar is vertical, horizontal, or ambiguous.	Medium5	MatrixImplementation	No attempts yet	1s	1024 MB	Judgeable
MarathonFind the largest finish time for Erik that gives him at least a 50 percent chance of beating every other runner, whose times are independent uniform intervals.	Medium5	Binary searchProbability	No attempts yet	2s	1024 MB	Judgeable
Bike PartyGiven N circular parties with alcohol gains and bike distances, find a start party where the alcohol level stays above zero until Robin returns to the start.	Medium5	Prefix sumArray+1	No attempts yet	1s	1024 MB	Judgeable
Longest Arithmetic SubsequenceGiven a sequence of N integers from 1 to 100, find the length of its longest subsequence whose consecutive terms share a common difference.	Medium5	Dynamic programmingArray	No attempts yet	2s	1024 MB	Judgeable
SproutsFind the largest gap between the median and the mean of sprout counts over every K x K block of an N x N grid, scaled by K squared.	Medium5	Sliding windowPrefix sum+1	No attempts yet	3s	1024 MB	Judgeable
Scenery 2Given n photo windows [a, b] that each need t time units, decide whether all n photographs can be taken without overlapping.	Medium5	GreedySorting+1	No attempts yet	1s	1024 MB	Judgeable
Siru's Department Store TourFind the shortest path on a grid from Siru's start to any chair, avoiding pillars and cells within Manhattan distance K of mannequins.	Medium5	BFSMatrix+1	No attempts yet	2s	1024 MB	Judgeable
K PrimesSplit N into a sum of K primes and print them, or print -1 if no such split exists.	Medium5	MathNumber theory+1	No attempts yet	1s	512 MB	Judgeable
200% Mixed Juice!Given bottles with volume and sugar, pick fractional amounts totaling exactly M liters to maximize sugar, printed as a reduced fraction.	Medium5	GreedySorting	No attempts yet	1s	1024 MB	Judgeable
SHOW ME THE DUNGEONPick monsters and a fighting order so the total health spent stays within K, maximizing the residents freed.	Medium5	Dynamic programmingSorting+1	No attempts yet	2s	512 MB	Judgeable
Drop 7Given a 7x7 grid and a ball number, pick the column to drop it in so that the fewest balls remain after all chain removals.	Medium5	SimulationBrute force	No attempts yet	1s	512 MB	Judgeable
Cutting the Long CakeCount the ways to make k-1 cuts in a cake of n cells so that every piece has the same number of toppings, modulo 1e9+7.	Medium5	CombinatoricsMath+1	No attempts yet	2s	512 MB	Judgeable
Inversion Parity and QueriesGiven a permutation of 1 to N under swap and reverse queries, print the parity of its inversion count after each query.	Medium5	MathImplementation	No attempts yet	2s	1024 MB	Judgeable
Artificial Neural NetworkGiven a network of linear neurons and Q input vectors, compute the network's output for each input.	Medium5	MathArray	No attempts yet	3s	1024 MB	Judgeable
Maximum LCMFor each N, find the largest LCM that three distinct numbers from 1 to N can have.	Medium5	MathNumber theory	No attempts yet	1s	1024 MB	Judgeable
Ball Draw Guessing GameFor each number, choose the probability p_i of answering red so that the blue-bag error stays at most q while the red-bag error is minimized.	Medium5	GreedySorting+1	No attempts yet	3s	1024 MB	Judgeable
Deletive EditingGiven words s and t, decide whether t can be reached from s by repeatedly deleting the first occurrence of a called letter.	Medium5	StringImplementation	No attempts yet	3s	512 MB	Judgeable
Heroes of MightFind the least dragon health that lets the dragon destroy all peasant groups when it hits one group for d damage per round.	Medium5	GreedyHeap+1	No attempts yet	3s	512 MB	Judgeable
CrammingFind the smallest first-day count for a strictly decreasing daily watch schedule over at most 7 days that totals exactly N videos.	Medium5	MathBinary search+1	No attempts yet	1s	1024 MB	Judgeable
Strange SwitchesFind the fewest presses of off switches needed to turn every switch on, where each press flips the switches it is wired to.	Medium5	BFSBit manipulation	No attempts yet	2s	1024 MB	Judgeable
Club federation tournament for the national university programming contestGiven a single-elimination record with one match missing, find every match result that would complete a valid bracket.	Medium5	TreeImplementation	No attempts yet	2s	1024 MB	Judgeable
Level UpGiven N character levels, raise the K lowest-leveled characters by 1 in each of M sessions, then print the final levels in ascending order.	Medium5	SortingGreedy+1	No attempts yet	1s	1024 MB	Judgeable
AbracadabraGiven a deck of N cards and a fixed modified riffle shuffle, answer Q queries for the card at position i after t shuffles.	Medium5	ArraySimulation+1	No attempts yet	3s	512 MB	Judgeable
Chalk ThiefPick a connected set of classrooms in a tree and steal the same amount from each, capped by the smallest chalk count in the set. Find the maximum total.	Medium5	Union-findSorting+1	No attempts yet	1s	512 MB	Judgeable
No-Edge PizzaTrack toppings on a circle of N slices; for each order, report whether every residue class mod l has one flavor and the minimum l-window sum.	Medium5	Hash mapMath+1	No attempts yet	1s	512 MB	Judgeable
StimulantGiven daily study and gaming hours and K stimulants that double the effect from their day on, find the maximum total skill with at most one stimulant per day.	Medium5	Prefix sumSorting+1	No attempts yet	10s	512 MB	Judgeable