Problems

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Total results29,442 problems

Tampered Records
Medium5
Dynamic programming, Binary search
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Bushil, the King of Short Coding
Medium5
Array, Sliding window
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Silver and Primes Both Start with S
Medium5
Simulation, Number theory+1
No attempts yet
Time limit
0.2s
Memory limit
1024 MB
Judgeable
Can't Do It at Home
Medium5
Math, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
A Plus B
Medium5
Heap, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Curious Sequence
Medium5
Math, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lazdynas
Medium5
Greedy, Hash map+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Untie
Medium5
Dynamic programming, String
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Intruder Outsmarting
Medium5
Number theory, Math+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Railroad Maintenance
Medium5
Graph, DFS
No attempts yet
Time limit
40s
Memory limit
1024 MB
Judgeable
Game Sort: Part 1
Medium5
String, Greedy
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Old Gold
Medium5
Dynamic programming, String
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Traitor
Medium5
Graph, BFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Doing Assignments Efficiently
Medium5
Dynamic programming, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Two Pointers (easy version)
Medium5
Sorting, Two pointers+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Love Letter
Medium5
Shortest path, Graph+1
No attempts yet
Time limit
2.5s
Memory limit
1024 MB
Judgeable
Folders
Medium5
Dynamic programming, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Checksum
Medium5
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Domino Stones
Medium5
Graph, BFS
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Word Groups
Medium5
Bit manipulation, Brute force+1
No attempts yet
Time limit
0.1s
Memory limit
1024 MB
Judgeable
Dotted Strips
Medium5
Greedy, Prefix sum
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
LED Scheme
Medium5
Graph, BFS+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Checkpoint running
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Game Board
Medium5
Prefix sum, Matrix+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Data Analysis
Medium5
Dynamic programming, Sorting+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Halma
Medium5
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Marss
Medium5
Dynamic programming, Matrix
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Puju
Medium5
Two pointers, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Acute Triangles
Medium5
Geometry, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Kuklite jagamine
Medium5
Two pointers, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Team Division
Medium5
Math, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Mars Car Numbers
Medium5
Combinatorics, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Broken Address Bus
Medium5
Bit manipulation, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tree Isomorphism
Medium5
Tree, DFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Weird Function
Medium5
Bit manipulation, Math+1
No attempts yet
Time limit
0.1s
Memory limit
1024 MB
Judgeable
Short Message 2
Medium5
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fridge Magnets
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Great Treaty of Byteland
Medium5
Geometry, Sorting
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Maximizing Flight Efficiency
Medium5
Shortest path, Matrix+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Wrong Bubble Sort
Medium5
Sorting, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Study Schedule Planning
Medium5
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Change Bulb States
Medium5
Greedy, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lost Purity
Medium5
Tree, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Top Salesperson
Medium5
Array, Implementation+1
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Building a Fence
Medium5
Sorting, Binary search+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Waiting
Medium5
Simulation, Queue+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Robotai
Medium5
Binary search, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tower
Medium5
Stack, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Powers of Two
Medium5
Brute force, Number theory+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Santa Claus
Medium5
Greedy, Array+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Vitamins
Medium5
Dynamic programming
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Cubes
Medium5
Intervals, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Making Rectangles
Medium5
Hash map, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Azber's Tooth Marks
Medium5
Array, Hash map+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Bridges
Medium5
Sorting, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Mountain Hike
Medium5
Sorting, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Trip Compulsion
Medium5
Sliding window, Union-find+2
No attempts yet
Time limit
24s
Memory limit
1024 MB
Judgeable
Love for Pizza
Medium5
Geometry, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Dice Poker
Medium5
Game theory, Brute force+1
No attempts yet
Time limit
6s
Memory limit
1024 MB
Judgeable
Malvika conducts her own contest series
Medium5
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Animesh decides to settle down
Medium5
Geometry, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Filling Shapes
Medium5
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Filling the Grid
Medium5
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Primes and Multiplication
Medium5
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Complete Tripartite
Medium5
Hash map, Graph+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Filling Diamonds
Medium5
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Powered Addition
Medium5
Greedy, Array+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Nested Rubber Bands
Medium5
Tree, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Robot Competition
Medium5
Binary search, BFS+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tournament
Medium5
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Discharge Mission
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
휴가 나가기
Medium5
Dynamic programming, Tree
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Close Triangles
Medium5
Brute force, Combinatorics+1
No attempts yet
Time limit
7s
Memory limit
1024 MB
Judgeable
Brightline - Back to the Future
Medium5
Shortest path, Graph
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Know your ABC's
Medium5
Dynamic programming, Combinatorics
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Cut the Cake
Medium5
Geometry, Two pointers+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Land Division
Medium5
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Not So Close
Medium5
Dynamic programming, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Card Game
Medium5
Greedy, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Travels
Medium5
Dynamic programming, Graph
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Like a Bridge over Troubled Freeways
Medium5
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Hurricane's Path
Medium5
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Water Contamination
Medium5
Graph, BFS
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Trasa
Medium5
Graph, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Train
Medium5
Prefix sum, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Asteroid belt
Medium5
Shortest path, Intervals
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Gathering Search Results
Medium5
Sorting, Greedy+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Exponentiation
Medium5
Math, Matrix+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Robot
Medium5
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Glass cutting
Medium5
Sorting, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cookies
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Potential Graph 1
Medium5
Matrix, Graph+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Umbrella Queries
Medium5
Math, Geometry
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Empty Quartz
Medium5
Combinatorics, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Drifting
Medium5
Graph, Shortest path+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Alien Prince's Social Party
Medium5
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Diameter of a Tree
Medium5
Tree, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Give Back My Streak!
Medium5
Simulation, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Knights' Journey
Medium5
BFS, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Odd Even Odd Even
Medium5
Segment tree, Bit manipulation
No attempts yet
Time limit
0.5s
Memory limit
16 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Tampered RecordsGiven n ranked pairs of solve counts where some values may be overwritten, find the fewest values to change so the list is sorted by afternoon, then morning, counts.	Medium5	Dynamic programmingBinary search	No attempts yet	8s	1024 MB	Judgeable
Bushil, the King of Short CodingDelete at most M of the N code lengths to maximize the sum of adjacent differences, which reduces to the last kept value minus the first.	Medium5	ArraySliding window	No attempts yet	1s	1024 MB	Judgeable
Silver and Primes Both Start with SGiven N, simulate the string A built over turns 1 to N, where prime turns reverse it, and count the B and S characters in the final A.	Medium5	SimulationNumber theory+1	No attempts yet	0.2s	1024 MB	Judgeable
Can't Do It at HomeGiven home and study room work times, travel time T, and sleep time S, find where to finish the assignment and the minimum time to submit it.	Medium5	MathSimulation	No attempts yet	1s	1024 MB	Judgeable
A Plus BGiven two sorted arrays A and B of length N, output the N smallest of all N^2 pairwise sums A[i] + B[j] in increasing order.	Medium5	HeapSorting	No attempts yet	1s	1024 MB	Judgeable
Curious SequenceGiven N, M, and a binary target X, find the expected sum of a uniformly random length-N sequence of M-bit values whose XOR equals X, modulo 1e9+7.	Medium5	MathBit manipulation	No attempts yet	1s	1024 MB	Judgeable
LazdynasGiven N nut coordinates, find the maximum number of nuts Squirrel Vytis can catch when the tree chooses the drop order.	Medium5	GreedyHash map+1	No attempts yet	1s	1024 MB	Judgeable
UntieGiven a circular string of R, P, and S, find the fewest characters to change so that no two neighboring characters are equal.	Medium5	Dynamic programmingString	No attempts yet	10s	1024 MB	Judgeable
Intruder OutsmartingEach wheel moves by plus or minus D on a cycle of N numbers. Find the fewest turns that make the wheel values a palindrome, or report that it is impossible.	Medium5	Number theoryMath+1	No attempts yet	5s	1024 MB	Judgeable
Railroad MaintenanceCount the train lines whose removal makes some pair of stations unreachable from each other, given the stations each line serves.	Medium5	GraphDFS	No attempts yet	40s	1024 MB	Judgeable
Game Sort: Part 1Given P strings, rearrange the letters inside each one so the resulting list is in non-decreasing lexicographic order, or report that it cannot be done.	Medium5	StringGreedy	No attempts yet	5s	1024 MB	Judgeable
Old GoldCount the gold placements that match each road marking's nearest-gold condition and leave at least one nugget, modulo 1000000007.	Medium5	Dynamic programmingString	No attempts yet	Not set	1024 MB	Judgeable
TraitorGiven friendships and the traitor's number, find the size of the largest group after the traitor splits his group apart.	Medium5	GraphBFS+1	No attempts yet	1s	1024 MB	Judgeable
Doing Assignments EfficientlyPick a subset of assignments to do shortest-first, maximizing points (half for late work within 24 hours), then report the least total time that achieves that maximum.	Medium5	Dynamic programmingSorting	No attempts yet	1s	1024 MB	Judgeable
Two Pointers (easy version)Given city positions and the starts of Alice and Bob, find the minimum total distance so every city is visited by one of them.	Medium5	SortingTwo pointers+1	No attempts yet	1s	1024 MB	Judgeable
Love LetterGiven dragons with distinct ages and free friend links, find the minimum letter-passing time from dragon 1 to every dragon.	Medium5	Shortest pathGraph+1	No attempts yet	2.5s	1024 MB	Judgeable
FoldersFind the minimum number of cursor moves to open the target file when each folder list can be reversed once with a button above its first item.	Medium5	Dynamic programmingImplementation	No attempts yet	1s	1024 MB	Judgeable
ChecksumFind the length N (at most 1000) and the digits K_i of a hidden periodic weight sequence, using checksum queries that contain no digit 0.	Medium5	MathImplementation	No attempts yet	2s	1024 MB	Judgeable
Domino StonesSplit N domino stones into two boxes so no symbol repeats within a box, or report impossible; print the lexicographically smallest split.	Medium5	GraphBFS	No attempts yet	1.5s	1024 MB	Judgeable
Word GroupsGiven N words over R letters, find the fewest letters so that every word contains at least one of the chosen letters.	Medium5	Bit manipulationBrute force+1	No attempts yet	0.1s	1024 MB	Judgeable
Dotted StripsCut a strip of L squares into as many length-M pieces with exactly N dots each as possible, where only some squares have dots.	Medium5	GreedyPrefix sum	No attempts yet	3s	1024 MB	Judgeable
LED SchemeGiven LEDs as directed edges between controller outputs, decide for each LED whether it can be the only one lit, meaning no other path leads from its anode to its cathode.	Medium5	GraphBFS+1	No attempts yet	3s	1024 MB	Judgeable
Checkpoint runningGiven N checkpoint positions on a line and a trip limit K, find the minimum total distance to visit all checkpoints, returning to the origin after each trip of at most K checkpoints.	Medium5	GreedySorting	No attempts yet	1s	1024 MB	Judgeable
Game BoardFind the K by K subgrid (K odd) where the gap between the two players' summed Manhattan distances to the center is smallest.	Medium5	Prefix sumMatrix+1	No attempts yet	1s	1024 MB	Judgeable
Data AnalysisSplit N points, sorted by x, into K contiguous groups so the total absolute deviation of y from one horizontal line per group is minimized.	Medium5	Dynamic programmingSorting+1	No attempts yet	3s	1024 MB	Judgeable
HalmaGiven a grid of pieces, find every empty cell that the piece marked # can reach in one move, either by a single step or a chain of jumps, and mark those cells with +.	Medium5	BFSGraph+1	No attempts yet	1s	1024 MB	Judgeable
MarssCount the square regions of size 2x2 or larger in an N by M grid whose two diagonals are all black and whose other cells are all white.	Medium5	Dynamic programmingMatrix	No attempts yet	1s	1024 MB	Judgeable
PujuGiven a row of N cells with thickets, find the largest plot Kazimir can reach after clearing thickets on a walk from S that uses at most K steps.	Medium5	Two pointersPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Acute TrianglesGiven N integer points (N up to 200), count the acute triangles they form, and how many of those are pairwise non-congruent.	Medium5	GeometrySorting+1	No attempts yet	2s	1024 MB	Judgeable
Kuklite jagamineGiven N boxes with cookie counts, choose a prefix and a suffix for Yuri so that his total and Mari's middle-part total differ as little as possible.	Medium5	Two pointersPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Team DivisionGiven N up to 10^18, each newbie joins the team that is winning at that moment; print the team that wins after all N have joined.	Medium5	MathSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Mars Car NumbersGiven N, find the lexicographically largest permutation in the first half and the smallest in the second half of all permutations of 1 to N.	Medium5	CombinatoricsImplementation	No attempts yet	1s	1024 MB	Judgeable
Broken Address BusGiven memory values and a working-wire mask per query, return the sum of values at addresses whose set bits all lie in that mask.	Medium5	Bit manipulationDynamic programming	No attempts yet	1s	1024 MB	Judgeable
Tree IsomorphismGiven two labeled trees with N nodes each, decide whether the first can be relabeled into the second, and if so print the new number for each node.	Medium5	TreeDFS+1	No attempts yet	1s	1024 MB	Judgeable
Weird FunctionGiven a positive integer a, find the largest gcd of (a XOR b) and (a AND b) over all b from 1 to a-1.	Medium5	Bit manipulationMath+1	No attempts yet	0.1s	1024 MB	Judgeable
Short Message 2Given N planet names made of lowercase letters, find the shortest string that contains every name as a substring.	Medium5	Dynamic programmingBit manipulation+1	No attempts yet	1s	1024 MB	Judgeable
Fridge MagnetsGiven N digit magnets and one plus sign, arrange them into two numbers whose sum is as small as possible, and output that minimum.	Medium5	GreedySorting	No attempts yet	1s	1024 MB	Judgeable
Great Treaty of BytelandGiven capital coordinates on a plane, list the kingdoms whose Voronoi cells are unbounded, which are the capitals on the convex hull boundary.	Medium5	GeometrySorting	No attempts yet	0.5s	1024 MB	Judgeable
Maximizing Flight EfficiencyCheck whether any direct flight is more expensive than a multi-stop route, and if not, count the direct flights that can be removed without changing any trip cost.	Medium5	Shortest pathMatrix+1	No attempts yet	0.5s	1024 MB	Judgeable
Wrong Bubble SortGiven N, output a length-N array of values from 0 to 10000 that Jeongyeon's bubble sort fails to sort correctly.	Medium5	SortingSimulation	No attempts yet	1s	1024 MB	Judgeable
Study Schedule PlanningAssign non-negative study hours to N subjects, with a total of at most T, to maximize the summed scores minus the fatigue penalty for the total hours.	Medium5	Dynamic programmingArray	No attempts yet	1s	1024 MB	Judgeable
Change Bulb StatesGiven N bulbs colored R, G, or B, find the fewest three-bulb operations (each shifts the colors one step) that make all bulbs one color, or -1.	Medium5	GreedyPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Lost PurityGiven a tree, add the fewest edges so that every vertex lies on a cycle, then print the endpoints of each added edge.	Medium5	TreeGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Top SalespersonGiven each employee's initial sales at their assigned stores, print after each sales record how many employees lead every store they are in charge of.	Medium5	ArrayImplementation+1	No attempts yet	1.5s	1024 MB	Judgeable
Building a FenceGiven fallen trees as start and end points and worker positions, find the total length of the sharpened tree pieces the workers reach while moving downward.	Medium5	SortingBinary search+1	No attempts yet	1s	1024 MB	Judgeable
WaitingGiven each guest's reserved hour and arrival hour at a single-table restaurant with a waiting line, find the longest wait from arrival to entry.	Medium5	SimulationQueue+1	No attempts yet	1s	1024 MB	Judgeable
RobotaiTwo robots start at both ends of a furrow of length L and plant M trees at given positions. Find the minimum time to plant all of them.	Medium5	Binary searchGreedy	No attempts yet	1s	1024 MB	Judgeable
TowerRepeatedly delete every monochrome run of at least K cubes from a tower until none remain, then print the surviving cubes from top to bottom.	Medium5	StackSimulation	No attempts yet	1s	1024 MB	Judgeable
Powers of TwoRearrange the digits of N into a number M with no leading zero so that the largest power of two divides M, then print M and that power.	Medium5	Brute forceNumber theory+1	No attempts yet	2s	1024 MB	Judgeable
Santa ClausGiven N houses and depots with gift counts, find how many gifts to load at the start and at each depot so the sleigh holds as few as possible at all times.	Medium5	GreedyArray+1	No attempts yet	1s	1024 MB	Judgeable
VitaminsGiven N tablets with their vitamin C, vitamin D, and price, find the minimum cost to get at least C mg of vitamin C and D mg of vitamin D.	Medium5	Dynamic programming	No attempts yet	2s	1024 MB	Judgeable
CubesCount the horizontal offsets where the upper part's full top row covers at least one cube of the lower part, and the two sparse rows never share a cell.	Medium5	IntervalsSorting+1	No attempts yet	1s	1024 MB	Judgeable
Making RectanglesPair up chosen sticks into rectangles that all share one perimeter, maximizing the total area of the rectangles.	Medium5	Hash mapSorting+1	No attempts yet	2s	1024 MB	Judgeable
Azber's Tooth MarksGiven sorted tooth mark positions, find every gap k where each mark has another mark exactly k away from it.	Medium5	ArrayHash map+1	No attempts yet	3s	1024 MB	Judgeable
BridgesFor each range L to R, find the bridge height M (floor average of the endpoints) and sum the scaffolding and tunnel costs over that range.	Medium5	SortingPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Mountain HikePick peaks so each new one is at least as high as all visited and no farther from the top peak; maximize total charm.	Medium5	SortingDynamic programming	No attempts yet	1s	1024 MB	Judgeable
Trip CompulsionGiven a weighted undirected graph, find the minimum possible gap between the longest and shortest road on a path from start to end.	Medium5	Sliding windowUnion-find+2	No attempts yet	24s	1024 MB	Judgeable
Love for PizzaGiven each topping's preference and center point on a pizza, find the maximum total preference of one wedge cut from the pizza.	Medium5	GeometrySorting+1	No attempts yet	2s	1024 MB	Judgeable
Dice PokerGiven each player's five first-round dice, find the probability that A wins when both players optimally reroll up to five dice once.	Medium5	Game theoryBrute force+1	No attempts yet	6s	1024 MB	Judgeable
Malvika conducts her own contest seriesGiven counts of easy, medium, and hard problems, find the most contests of three types that can run with no two adjacent contests sharing a type.	Medium5	MathGreedy	No attempts yet	1s	1024 MB	Judgeable
Animesh decides to settle downGiven n convex polygons, find the area of the region that lies inside all of them.	Medium5	GeometryImplementation	No attempts yet	1s	1024 MB	Judgeable
Filling ShapesCount the ways to fill a 3 by n grid of tiles with the shape from the picture, with no gaps and no overlaps, for n up to 60.	Medium5	Dynamic programmingCombinatorics	No attempts yet	1s	1024 MB	Judgeable
Filling the GridGiven the required run lengths of full cells from the left in each row and from the top in each column, count the grid fillings that match them, modulo 1000000007.	Medium5	MathImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Primes and MultiplicationGiven x and n, compute the product of f(x, y) for y from 1 to n, modulo 10^9+7, where f(x, y) multiplies the largest power of each prime of x that divides y.	Medium5	Number theoryMath	No attempts yet	1s	1024 MB	Judgeable
Complete TripartiteGiven an undirected graph, split the vertices into three nonempty sets, each independent, with every pair of sets fully joined by edges, or report -1.	Medium5	Hash mapGraph+1	No attempts yet	2s	1024 MB	Judgeable
Filling DiamondsCount the ways to cover a belt-shaped region of 4n-2 triangles with diamonds, for up to 10^4 queries with n up to 10^9.	Medium5	CombinatoricsMath	No attempts yet	1s	1024 MB	Judgeable
Powered AdditionEach second x, you may add 2^(x-1) to any chosen elements. Find the smallest T that makes the array nondecreasing.	Medium5	GreedyArray+1	No attempts yet	1s	1024 MB	Judgeable
Nested Rubber BandsGiven a tree of n vertices, find the largest set of pairwise non-adjacent vertices that can be nested as rubber bands.	Medium5	TreeDynamic programming	No attempts yet	1s	1024 MB	Judgeable
Robot CompetitionFind the largest side length of a square robot that can travel from the left edge to the right edge of a grid maze with wall cells.	Medium5	Binary searchBFS+2	No attempts yet	1s	1024 MB	Judgeable
TournamentGiven a bracket order A and k proposed orders, check whether each proposed order makes every pair of players meet in the same round as A.	Medium5	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
Discharge MissionKim can reorder the floors of each base, so the task is to decide whether his combat power can beat every enemy across all N bases.	Medium5	GreedySorting	No attempts yet	1s	1024 MB	Judgeable
휴가 나가기Given tasks with importance, processing time, and at most one prerequisite each, find the minimum total time to reach importance S.	Medium5	Dynamic programmingTree	No attempts yet	1s	1024 MB	Judgeable
Close TrianglesGiven 3n points (n up to 5), partition them into n triangles to minimize the gap between the largest and smallest triangle areas.	Medium5	Brute forceCombinatorics+1	No attempts yet	7s	1024 MB	Judgeable
Brightline - Back to the FutureGiven directed blue lines (aging riders) and red lines (rewinding riders), list every city reachable from city 1 where a rider arrives younger than they started.	Medium5	Shortest pathGraph	No attempts yet	2s	1024 MB	Judgeable
Know your ABC'sCount the strings with a A's, b B's, and c C's where no two adjacent letters match, modulo 10^9 + 7.	Medium5	Dynamic programmingCombinatorics	No attempts yet	2s	1024 MB	Judgeable
Cut the CakeGiven a convex polygon, find the diagonal between two vertices that splits it into two pieces with the smallest area difference.	Medium5	GeometryTwo pointers+1	No attempts yet	2s	1024 MB	Judgeable
Land DivisionGiven a trapezoid's two bases and height, find the smallest achievable gap between the largest and smallest of the four triangles cut by one interior point.	Medium5	GeometryMath	No attempts yet	1s	1024 MB	Judgeable
Not So CloseCount the placements of condos on an r by c grid where no two condos touch, including diagonally, modulo 1e9+7.	Medium5	Dynamic programmingBit manipulation	No attempts yet	1s	1024 MB	Judgeable
Card GameSeongho removes cards from a deck, scoring odd-position picks and freely removing even-position ones; find the maximum final score.	Medium5	GreedyImplementation	No attempts yet	2s	1024 MB	Judgeable
TravelsGiven cities joined by one-way rails from lower to higher numbers, with some tickets unsold, sum the pleasure of every trip of at least two cities, modulo 1e9+7.	Medium5	Dynamic programmingGraph	No attempts yet	1s	1024 MB	Judgeable
Like a Bridge over Troubled FreewaysPlace c crossings on the x-axis so the average of each animal's walk (\|y\| plus horizontal distance to the nearest crossing) is minimized.	Medium5	Dynamic programmingSorting+1	No attempts yet	1s	1024 MB	Judgeable
The Hurricane's PathGiven hurricane waypoints with arrival times, find the largest total rain any point of interest collects, where rain rate is 1/(1+d)^2.	Medium5	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Water ContaminationGiven contaminated and important locations joined by connections, find the fewest connections to block so no important location gets contaminated.	Medium5	GraphBFS	No attempts yet	1s	1024 MB	Judgeable
TrasaGiven an undirected road graph, find the longest route that repeats no city and whose inner cities have exactly two roads each.	Medium5	GraphImplementation	No attempts yet	1s	1024 MB	Judgeable
TrainGiven passenger counts per car, find the minimum total number of car-to-car moves so that every car ends with exactly K passengers.	Medium5	Prefix sumGreedy	No attempts yet	1s	1024 MB	Judgeable
Asteroid beltFind the minimum vertical fuel needed to fly from the start square to the destination through empty row intervals, where horizontal flight is free.	Medium5	Shortest pathIntervals	No attempts yet	1s	1024 MB	Judgeable
Gathering Search ResultsGiven k search engine rankings of n results, output one combined ranking that minimizes the sum of squared position differences across all engines.	Medium5	SortingGreedy+1	No attempts yet	3s	1024 MB	Judgeable
ExponentiationGiven alpha, beta, and m, compute x^beta + 1/x^beta mod m, where x + 1/x = alpha and all inputs are below 2^64.	Medium5	MathMatrix+1	No attempts yet	3s	1024 MB	Judgeable
RobotFind the largest number of cells a robot can clean on an N by M grid, starting from any free cell facing any direction and turning right at each obstacle.	Medium5	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Glass cuttingGiven an M by N pane with K point defects, find the largest axis-parallel rectangle that has no defect strictly inside it.	Medium5	SortingBrute force+1	No attempts yet	1s	1024 MB	Judgeable
CookiesTwo brothers alternately take cookies to maximize their own score minus the other's, and the task asks for the final value of A-B.	Medium5	GreedySorting	No attempts yet	1s	1024 MB	Judgeable
Potential Graph 1Given a weighted connected graph, fix f at 1 for vertex 1 and 0 for vertex N, then find g_f(1) when g_f is zero at every interior vertex.	Medium5	MatrixGraph+1	No attempts yet	2s	1024 MB	Judgeable
Umbrella QueriesFor a regular N-gon, count pairs of segments that share a vertex and meet at a right angle, for each given N.	Medium5	MathGeometry	No attempts yet	2s	1024 MB	Judgeable
Empty QuartzCount the 0/1 strings of length N where exactly K intervals contain an odd number of 1s, modulo 998244353, for T queries.	Medium5	CombinatoricsPrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
DriftingFind the minimum weight path from vertex 1 to vertex N in a DAG where certain consecutive edge pairs (a, b, c) are forbidden.	Medium5	GraphShortest path+1	No attempts yet	2s	1024 MB	Judgeable
Alien Prince's Social PartyGiven A bottles of wine, B loaves of bread, and at most K single-unit spells, find the largest number of guests who can each get equal shares with nothing left over.	Medium5	Number theoryMath	No attempts yet	1s	1024 MB	Judgeable
Diameter of a TreeBuild a tree on N vertices where every vertex has degree at most K and the diameter is as small as possible, then print its edges.	Medium5	TreeGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Give Back My Streak!Given daily problem counts, find the longest streak when a Streak Freeze covers zero-solve days and is rebought two days after each use.	Medium5	SimulationGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Knights' JourneyGiven two 4x4 boards of knights, find the minimum number of knight moves that turns the arrangement on board A into board B.	Medium5	BFSBit manipulation	No attempts yet	1s	1024 MB	Judgeable
Odd Even Odd EvenGiven an array of N zeros, process Q queries that add w to a range and count the odd and even values in a range.	Medium5	Segment treeBit manipulation	No attempts yet	0.5s	16 MB	Judgeable