Problems

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Total results29,342 problems

One more line
Medium6
Math, Geometry+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Visit All Rooms in the Building
Medium6
Dynamic programming, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Concert
Medium6
Segment tree, Array+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Longest distinct segment queries
Medium6
Array, Binary search
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Finding a Tree Connected Component
Medium6
Tree, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
2023 Is the Year of the Black Rabbit (Hard)
Medium6
Dynamic programming, String matching
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Spacious Sets
Medium6
Sorting, Greedy+1
No attempts yet
Time limit
20s
Memory limit
1024 MB
Judgeable
Railroad Management
Medium6
Graph, Greedy+1
No attempts yet
Time limit
40s
Memory limit
1024 MB
Judgeable
Lara and Yongmaek Conversion
Medium6
Greedy, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hekaton
Medium6
Graph, BFS
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Immunization Operation
Medium6
Sorting, Simulation+2
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Genetic Sequences
Medium6
String matching, String
No attempts yet
Time limit
20s
Memory limit
1024 MB
Judgeable
Safe Stock (Easy)
Medium6
Matrix, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Why won't this work
Medium6
String, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Professor Won has too many assignments
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bitwise Expression
Medium6
Segment tree, Bit manipulation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Deleting Segments
Medium6
Intervals, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Edge Deletion
Medium6
Dynamic programming, Tree+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Covering the Floor
Medium6
Geometry, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Pendulum Cookie
Medium6
Dynamic programming, Bit manipulation
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Catapult-Carousel
Medium6
Math, Number theory
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Magical BF 1
Medium6
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ribbon
Medium6
Sorting, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lottery
Medium6
Probability, Combinatorics+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Veenus
Medium6
Tree, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Side Network
Medium6
Tree, DFS+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Coalitions
Medium6
Brute force, Sorting+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Frugal testing
Medium6
Brute force, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Color Mixing
Medium6
Tree, Divide and conquer
No attempts yet
Time limit
1.2s
Memory limit
1024 MB
Judgeable
Exam
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rocket
Medium6
Dynamic programming, Divide and conquer+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Garden
Medium6
Geometry, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Optimizing Mo's Algorithm
Medium6
Sorting, Sliding window+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
프로그래밍 동아리
Medium6
Segment tree, Heap+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Server Relocation
Medium6
Recursion, Simulation
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Short message 4
Medium6
String, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Painting the City Intersections
Medium6
Graph, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Text Difference
Medium6
Trie, String+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Prisoners
Medium6
Graph, Geometry+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
NNN-numbers
Medium6
Backtracking, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Onix
Medium6
Backtracking, Dynamic programming+1
No attempts yet
Time limit
30s
Memory limit
1024 MB
Judgeable
Sorting
Medium6
Array, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Best Fair Shuffles
Medium6
Array, Math+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Challenging Hike
Medium6
DFS, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Detour
Medium6
Graph, Shortest path
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Honest Worker
Medium6
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Factorial Factors
Medium6
Number theory, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Permutation Gifts
Medium6
Number theory, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Domino Sequence
Medium6
Dynamic programming, Greedy
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Tier and Rank
Medium6
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Slicing Trees and Checking Paths
Medium6
Tree, DFS
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Natural Number Sums
Medium6
Dynamic programming, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
25th Hour, at the Night Contest
Medium6
Implementation, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Hotel Assignment
Medium6
Tree, Dynamic programming
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Cheeseburger
Medium6
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
POPCOUNT
Medium6
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Succession
Medium6
Dynamic programming, Tree+1
No attempts yet
Time limit
12s
Memory limit
1024 MB
Judgeable
Paper Presentation
Medium6
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Palindromic paths
Medium6
Dynamic programming, Graph+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Soccer Teams
Medium6
Number theory, Dynamic programming
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Sales Prediction
Medium6
Matrix, Math
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Dividing Stones
Medium6
Dynamic programming, Hash map+1
No attempts yet
Time limit
7s
Memory limit
1024 MB
Judgeable
Animesh practices some programming contests
Medium6
Dynamic programming, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Malvika gets bored along with her Cats
Medium6
Array, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Malvika conducts a Programming Camp
Medium6
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
King Animesh decides to have a voyage to the sun
Medium6
Union-find, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Malvika and Animesh play Red-Blue Card Game
Medium6
Game theory, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Product Oriented Recurrence
Medium6
Matrix, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Another Filling the Grid
Medium6
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Edge Weight Assignment
Medium6
Tree, BFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fox's Dream
Medium6
Recursion, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Make String 1
Medium6
String, Implementation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Crossing the stepping stones backward
Medium6
Dynamic programming, Bit manipulation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Most Valuable Pez
Medium6
Dynamic programming, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
The Duel of Smokin' Joe
Medium6
Game theory, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Tree and XOR
Medium6
Tree, DFS+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
N-Queen (mod N)
Medium6
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Trucks
Medium6
Minimum spanning tree, Union-find+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Deer Hunter
Medium6
BFS, Geometry+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Mud Flow
Medium6
Topological sort, Graph+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Cleanup
Medium6
Dynamic programming, Prefix sum+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Easter Eggs
Medium6
Graph, Tree+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Baked Goods
Medium6
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Girlianda
Medium6
Tree, DFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Robot
Medium6
Simulation, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Flea
Medium6
Graph, BFS+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Determining Duos
Medium6
Greedy, Sorting
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Losing Leaves
Medium6
Dynamic programming, Tree
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Monorail
Medium6
Dynamic programming, Greedy+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Cutting into Monotone Increasing Sequence
Medium6
Dynamic programming, String+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Heap Structure
Medium6
Tree, Binary search+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Numbers
Medium6
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sum of Product of Binomial Coefficients
Medium6
Math, Combinatorics
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Strawberries in a Box
Medium6
Matrix, Prefix sum+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Camp room assignment
Medium6
Combinatorics, Math
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Digit-only subrectangles
Medium6
Prefix sum, Math+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Bubble Sort
Medium6
Greedy, Segment tree+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
K-Divisible Graph
Medium6
Graph, Union-find+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Daegu Science High School Bet
Medium6
Sorting, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Daegu Ilgwa Science High School
Medium6
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
One more lineGiven a grid of lines x=0..n and y=0..n plus one segment between two cell centers, count the axis-parallel rectangles whose sides lie on those lines.	Medium6	MathGeometry+1	No attempts yet	1s	1024 MB	Judgeable
Visit All Rooms in the BuildingFind the minimum time to visit all N given rooms in an H by W building, starting at floor 1 room 1, where a same-floor step costs 1 second and a floor change costs 100.	Medium6	Dynamic programmingGreedy+1	No attempts yet	1s	1024 MB	Judgeable
ConcertAfter each point update to an array, find the contiguous range with the largest average, breaking ties by longer length, then by smaller left index.	Medium6	Segment treeArray+1	No attempts yet	3s	1024 MB	Judgeable
Longest distinct segment queriesGiven a sequence of N values and Q queries (l, r), find the length of the longest contiguous subarray inside [l, r] whose values are all distinct.	Medium6	ArrayBinary search	No attempts yet	1s	1024 MB	Judgeable
Finding a Tree Connected ComponentGiven a rooted tree and several vertex sets, report the vertex count and vertex-number sum of the smallest connected subtree containing each set.	Medium6	TreeSorting	No attempts yet	1s	1024 MB	Judgeable
2023 Is the Year of the Black Rabbit (Hard)Count the serial numbers from 1 to N that contain 2023 as a subsequence, where N can be as large as 10^18.	Medium6	Dynamic programmingString matching	No attempts yet	2s	512 MB	Judgeable
Spacious SetsFor each A_i, find the largest set chosen from list A that contains A_i and keeps every pair of elements at least K apart.	Medium6	SortingGreedy+1	No attempts yet	20s	1024 MB	Judgeable
Railroad ManagementGiven each station's single outgoing shipment and its car count, find the fewest initial cars so every shipment can run in some order.	Medium6	GraphGreedy+1	No attempts yet	40s	1024 MB	Judgeable
Lara and Yongmaek ConversionGiven N yongmaek kinds in a line and monster health H, find the fewest Yongmaek Conversion uses needed to defeat all monsters, or print -1 if impossible.	Medium6	GreedyDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
HekatonMove warriors along one-way edges between weak points, then report the minimum warrior count each weak point can end with, given the focus targets.	Medium6	GraphBFS	No attempts yet	1s	1024 MB	Judgeable
Immunization OperationGiven each vaccine's pickup and delivery points and a list of east or west moves, count the vaccinations completed during each move.	Medium6	SortingSimulation+2	No attempts yet	Not set	1024 MB	Judgeable
Genetic SequencesGiven strings A and B, answer each query (P, S) with the length of the longest substring of A's first P letters that is also a prefix of B's last S letters.	Medium6	String matchingString	No attempts yet	20s	1024 MB	Judgeable
Safe Stock (Easy)Given p, c, k and the first p balances, compute \|D_k\| mod 1e9+7, where D_k follows a linear recurrence with ratio c.	Medium6	MatrixMath	No attempts yet	1s	1024 MB	Judgeable
Why won't this workGiven a string, find the minimum energy to delete all letters except H, Y, and U using single-key or contiguous drag deletions, and the max number of HYU words.	Medium6	StringDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Professor Won has too many assignmentsChoose assignments that each start on a distinct day and finish by their deadline, and find the fewest bots needed to reach total points C.	Medium6	GreedySorting+1	No attempts yet	1s	1024 MB	Judgeable
Bitwise ExpressionStarting from 0, apply a list of AND, OR, and XOR operations left to right, and print the final value after each of Q single-operation replacements.	Medium6	Segment treeBit manipulation+1	No attempts yet	2s	1024 MB	Judgeable
Deleting SegmentsDelete the cheapest set of segments on a number line so that no group of mutually connected overlapping segments has more than K members.	Medium6	IntervalsDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Edge DeletionGiven a tree with up to 10^6 vertices, find the minimum number of edges to remove so that every component is an even tree.	Medium6	Dynamic programmingTree+1	No attempts yet	3s	1024 MB	Judgeable
Covering the FloorGiven an X by Y floor and two rotatable rectangular sheets, find a placement of one or two sheets that covers the floor without cutting or folding, or report that it is impossible.	Medium6	GeometryImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Pendulum CookieAssign N given jump lengths alternately to right and left jumps, then list every square the jumper can finish on.	Medium6	Dynamic programmingBit manipulation	No attempts yet	3s	1024 MB	Judgeable
Catapult-CarouselGiven N seats and S affine jumps, find where seat U ends up after K rides, where K can be negative.	Medium6	MathNumber theory	No attempts yet	1s	1024 MB	Judgeable
Magical BF 1Write a BF program that leaves x minus y in cell M0, where M0 and M1 hold x and y with 0 ≤ y ≤ x ≤ 200, and the grid reads correctly by rows and by columns.	Medium6	ImplementationSimulation	No attempts yet	1s	1024 MB	Judgeable
RibbonGiven the ribbon piece length of each of N elves, find integer holding positions that the midpoint-cutting machine could produce, or report EI.	Medium6	SortingMath+1	No attempts yet	1s	1024 MB	Judgeable
LotteryEach ramp section is removed with probability A/B, so find the expected prize of the basket the ball lands in, modulo 1e9+7.	Medium6	ProbabilityCombinatorics+1	No attempts yet	2s	1024 MB	Judgeable
VeenusGiven a rooted tree and a stream of toggles on node danger levels, report the lowest common ancestor of all currently high-danger nodes after each toggle.	Medium6	TreeSorting+1	No attempts yet	1s	1024 MB	Judgeable
Side NetworkGiven a tree of N servers, remove two servers and find the maximum (T=1) or minimum (T=2) sum of squared component sizes.	Medium6	TreeDFS+1	No attempts yet	3s	1024 MB	Judgeable
CoalitionsCount the groups of parties that hold more than half of the N seats, where removing any single party leaves N/2 seats or fewer.	Medium6	Brute forceSorting+1	No attempts yet	3s	1024 MB	Judgeable
Frugal testingPick the smallest test set that fails every incorrect solution to the Assembling times task, which asks for two hh:mm times with the largest possible sum.	Medium6	Brute forceImplementation	No attempts yet	1s	1024 MB	Judgeable
Color MixingFor each requested RGB color, print the index of the machine shade closest in Manhattan distance, choosing the smaller index on ties.	Medium6	TreeDivide and conquer	No attempts yet	1.2s	1024 MB	Judgeable
ExamGiven N easy or hard problems with mandatory times t_i, find the leave time and solved set that maximize points without leaving any mandatory problem unsolved.	Medium6	GreedySorting+1	No attempts yet	1s	1024 MB	Judgeable
RocketSplit an array of N distinct values into K contiguous segments so that the total number of inversions inside the segments is minimal.	Medium6	Dynamic programmingDivide and conquer+1	No attempts yet	1s	1024 MB	Judgeable
GardenGiven a closed polygon fence and a viewer position, list the fence segments whose visible part has a length greater than zero.	Medium6	GeometryBrute force	No attempts yet	1s	1024 MB	Judgeable
Optimizing Mo's AlgorithmReorder the Q range-sum queries on an array so that the given two-pointer code performs as few pointer moves as possible.	Medium6	SortingSliding window+1	No attempts yet	1s	1024 MB	Judgeable
프로그래밍 동아리Given each member's attendance interval, output the problem solved each week: the smallest number no attending member has solved yet.	Medium6	Segment treeHeap+1	No attempts yet	1s	1024 MB	Judgeable
Server RelocationGiven N servers in rack A and which ones are manufacturer X, print the fewest moves that send X servers to rack B and Y servers to rack C.	Medium6	RecursionSimulation	No attempts yet	3s	1024 MB	Judgeable
Short message 4Build the shortest lowercase string that contains every given planet name as a substring.	Medium6	StringDynamic programming+2	No attempts yet	1s	1024 MB	Judgeable
Painting the City IntersectionsColor each intersection of a planar street graph with at most 10 colors so that no street joins two intersections of the same color.	Medium6	GraphGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Text DifferenceGiven N strings, find the sum over all ordered pairs of the fewest append and delete-last operations needed to turn one string into the other.	Medium6	TrieString+1	No attempts yet	1s	1024 MB	Judgeable
PrisonersFind the fewest guards to remove so that a path from the west wall to the east wall keeps more than 100 meters from every guard.	Medium6	GraphGeometry+1	No attempts yet	1s	1024 MB	Judgeable
NNN-numbersGiven N, list all N-digit base-N numbers where each digit equals how many times its position's digit value appears, in increasing order.	Medium6	BacktrackingMath+1	No attempts yet	1s	1024 MB	Judgeable
OnixCount the paths that visit every cell of an N by N grid exactly once, starting at the top-left cell and ending at the bottom-left cell, for N up to 8.	Medium6	BacktrackingDynamic programming+1	No attempts yet	30s	1024 MB	Judgeable
SortingGiven a sequence of N integers, find the minimum number of contiguous blocks that can be reordered as whole blocks to produce a sorted sequence.	Medium6	ArrayGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Best Fair ShufflesGiven a permutation of 1 to N, find the fewest fair shuffles (split the deck, then interleave the two parts) that turn 1 2 ... N into it.	Medium6	ArrayMath+1	No attempts yet	0.5s	1024 MB	Judgeable
Challenging HikeFor each landmark, find the longest strictly increasing subsequence of scores along the path from landmark 1 to that landmark in a tree.	Medium6	DFSDynamic programming+2	No attempts yet	1s	1024 MB	Judgeable
DetourFor each road segment, find the shortest route between its two endpoints that does not use that segment directly, or -1 if none exists.	Medium6	GraphShortest path	No attempts yet	5s	1024 MB	Judgeable
Honest WorkerChoose non-overlapping contractor jobs, each optionally quit early, to maximize total pay minus fake cover letter costs.	Medium6	Dynamic programmingSorting+1	No attempts yet	1s	1024 MB	Judgeable
Factorial FactorsGiven A and B up to 1,000,000, the task asks for the sum of s(n) over n from A to B, where s(n) is the smallest m whose factorial is divisible by n.	Medium6	Number theorySorting+1	No attempts yet	1s	1024 MB	Judgeable
Permutation GiftsFind an ordering of 1 to N where every prefix sum is composite (not prime), or report NO if no such ordering exists.	Medium6	Number theoryGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Domino SequenceGiven a sequence of N numbers, find the length of the longest subsequence where each element is at most the sum of all elements before it.	Medium6	Dynamic programmingGreedy	No attempts yet	1.5s	1024 MB	Judgeable
Tier and RankGiven tiers that split N ranked users into tiers and subtiers, find the min and max rank a bragged tier can have, or report invalid or liar.	Medium6	ImplementationMath+1	No attempts yet	1s	256 MB	Judgeable
Slicing Trees and Checking PathsGiven a tree, for each query remove the edges on the path from a to b and report whether c and d are still connected.	Medium6	TreeDFS	No attempts yet	4s	1024 MB	Judgeable
Natural Number SumsCount sets of distinct integers from 1 to N, none a multiple of K, with an even number of elements that sum to N, modulo 998244353.	Medium6	Dynamic programmingMath	No attempts yet	1s	1024 MB	Judgeable
25th Hour, at the Night ContestGiven the mine layout of the first row and each cell's count of safe neighbors, the task is to reconstruct the full n by n mine grid.	Medium6	ImplementationMath+1	No attempts yet	2s	1024 MB	Judgeable
Hotel AssignmentGiven a tree of N hotels, choose K distinct hotels so that the sum of pairwise distances among them is maximized.	Medium6	TreeDynamic programming	No attempts yet	2s	1024 MB	Judgeable
CheeseburgerEach farm supplies only the chain stores nearest to it, and each store pays the cheapest price among farms that can supply it. Output that price per store, or -1.	Medium6	Shortest pathGraph	No attempts yet	1s	1024 MB	Judgeable
POPCOUNTGiven N, A, and B, the task is to sum f(i) for i from 1 to N, where f(i) is the maximum of A times popcount(a) plus B times popcount(b) over all splits a+b=i.	Medium6	Dynamic programmingBit manipulation+1	No attempts yet	1s	1024 MB	Judgeable
SuccessionPick exactly K areas that form a connected subtree of the road tree to maximize total value, then count the ways to achieve that maximum modulo 1000000007.	Medium6	Dynamic programmingTree+1	No attempts yet	12s	1024 MB	Judgeable
Paper PresentationCount the orderings of 2M papers split into two slots of M each, where every dependent scientist must share a slot with the scientist they depend on.	Medium6	Dynamic programmingBit manipulation+1	No attempts yet	4s	1024 MB	Judgeable
Palindromic pathsFind the longest path from point 0 to point N-1 in a complete directed graph whose edge labels read as a palindrome, lexicographically smallest on ties.	Medium6	Dynamic programmingGraph+1	No attempts yet	3s	1024 MB	Judgeable
Soccer TeamsGiven counts of digits 1 to 9 and unlimited zeros, find the fewest digits of a multiple of 11 that uses all the nonzero digits.	Medium6	Number theoryDynamic programming	No attempts yet	5s	1024 MB	Judgeable
Sales PredictionGiven a linear recurrence of order R, compute the sum of every Kth term over the first N such terms, modulo 1,000,000,007.	Medium6	MatrixMath	No attempts yet	10s	1024 MB	Judgeable
Dividing StonesGiven N and P, count the distinct values that the product of pile sizes modulo P can take over all ways to split N stones into piles.	Medium6	Dynamic programmingHash map+1	No attempts yet	7s	1024 MB	Judgeable
Animesh practices some programming contestsPick at most one problem per contest within the time limit, using at most k swaps between contests, to maximize total pleasure.	Medium6	Dynamic programmingBit manipulation	No attempts yet	1s	1024 MB	Judgeable
Malvika gets bored along with her CatsGiven bar lengths in a row, find the fewest picks needed to eat every bar, where each pick also eats all bars forming an inversion with the picked bar.	Medium6	ArrayGreedy	No attempts yet	1s	1024 MB	Judgeable
Malvika conducts a Programming CampFind the minimum hours for n people in a line to learn m topics, where Malvika at the end teaches and each hour one neighbour teaches another.	Medium6	MathGreedy	No attempts yet	1s	1024 MB	Judgeable
King Animesh decides to have a voyage to the sunGiven some edge costs of a complete bipartite graph where every perfect matching has equal cost, find the sum of squares of all N^2 edge costs modulo 1e9+7.	Medium6	Union-findMath+1	No attempts yet	1s	1024 MB	Judgeable
Malvika and Animesh play Red-Blue Card GameGiven a row of R and B cards, two players alternately flip a red card and any run of blue cards to its right. Find the winner under optimal play.	Medium6	Game theoryBit manipulation	No attempts yet	1s	1024 MB	Judgeable
Product Oriented RecurrenceGiven a multiplicative recurrence with c^(2x-6) factors and n up to 10^18, compute f_n modulo 10^9+7.	Medium6	MatrixMath+1	No attempts yet	1s	1024 MB	Judgeable
Another Filling the GridCount the ways to fill an n by n grid with integers from 1 to k so that every row and every column has minimum 1, modulo 1e9+7.	Medium6	CombinatoricsMath	No attempts yet	1s	1024 MB	Judgeable
Edge Weight AssignmentGiven a tree, assign positive edge weights so every leaf-to-leaf path XOR is zero, and find the minimum and maximum count of distinct weights.	Medium6	TreeBFS+1	No attempts yet	1s	1024 MB	Judgeable
Fox's DreamGiven N disks that all start on peg K, find the minimum number of moves to reach the target peg for each disk, modulo 1000000007.	Medium6	RecursionMath	No attempts yet	2s	1024 MB	Judgeable
Make String 1Given a string of equal S and U counts, print a sequence of cursor operations that builds it in at most 2N operations.	Medium6	StringImplementation+1	No attempts yet	2s	1024 MB	Judgeable
Crossing the stepping stones backwardCount the self-avoiding paths from stone 1 to stone N when each move jumps forward by 1 to K or steps back by 1, modulo 1000000007.	Medium6	Dynamic programmingBit manipulation	No attempts yet	2s	1024 MB	Judgeable
Most Valuable PezGiven n dispensers of 12 ordered candy values each, pick exactly k candies taken as top-down prefixes from each dispenser to maximize total value.	Medium6	Dynamic programmingPrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
The Duel of Smokin' JoeGiven a permutation, decide whether the first player wins a game where players swap unfixed elements until sorted and the last swap wins.	Medium6	Game theoryMath+1	No attempts yet	2s	1024 MB	Judgeable
Tree and XORFor each root r, find the minimum cost to make all vertex values equal, where XOR-ing a subtree by c costs its size times c.	Medium6	TreeDFS+1	No attempts yet	3s	1024 MB	Judgeable
N-Queen (mod N)Given N, place N queens on an N by N board whose opposite edges are joined, so no two share a row, column, or wrapped diagonal. Print one valid placement, or -1 if none exists.	Medium6	MathImplementation	No attempts yet	1s	512 MB	Judgeable
TrucksGiven roads with travel times, answer each query by checking whether a driver can get from city a to city b when every road on the route fits within the rest limit p.	Medium6	Minimum spanning treeUnion-find+1	No attempts yet	1s	1024 MB	Judgeable
The Deer HunterFind the shortest chase time for P-22 to catch a deer that flees straight away after he steps on a noisy cell, or -1 if he cannot.	Medium6	BFSGeometry+1	No attempts yet	3s	1024 MB	Judgeable
Mud FlowGiven a grid of heights, soil, rain, and dislodging thresholds, find the largest amount of soil that settles on any single cell after mud flows downhill.	Medium6	Topological sortGraph+1	No attempts yet	4s	1024 MB	Judgeable
CleanupGroup the sorted debris sites into piles, paying T per pile plus the bulldozing cost to each pile's weighted median, and find the minimum total time.	Medium6	Dynamic programmingPrefix sum+1	No attempts yet	8s	1024 MB	Judgeable
Easter EggsEach child passes eggs along fixed wish edges, and every child is wanted by at most one other. Find the most children who can get an egg when the Bunny starts with M eggs.	Medium6	GraphTree+2	No attempts yet	1s	1024 MB	Judgeable
Baked GoodsGiven a budget S and two cupcake types, each with an ingredient cost and a profit, find the maximum total profit from an affordable whole-number mix of the two.	Medium6	Brute forceMath	No attempts yet	1s	1024 MB	Judgeable
GirliandaGiven a tree of N bulbs with an initial on/off state, find the first second at which every bulb is off, or -1 if that never happens.	Medium6	TreeDFS+1	No attempts yet	1s	1024 MB	Judgeable
RobotFind the most cells a robot can clean on a grid, moving straight until blocked, turning right each time, from any free start and direction.	Medium6	SimulationGraph+1	No attempts yet	1s	1024 MB	Judgeable
FleaCount the cells of an N by M grid where a flea that jumps up to K cells in each glue's weak direction can eventually leave the grid.	Medium6	GraphBFS+1	No attempts yet	2s	1024 MB	Judgeable
Determining DuosGiven r score rankings of 2n students, decide if n pairs can be formed whose summed per-topic maxima reach rn(3n+1)/2.	Medium6	GreedySorting	No attempts yet	3s	1024 MB	Judgeable
Losing LeavesGiven a rooted tree and k, sell exactly k nodes closed under descendants so that the fewest leaf nodes remain in the network.	Medium6	Dynamic programmingTree	No attempts yet	8s	1024 MB	Judgeable
MonorailSchedule entry times for trains in both directions through a single-track tunnel so opposite trains never overlap, minimizing total waiting.	Medium6	Dynamic programmingGreedy+1	No attempts yet	2s	1024 MB	Judgeable
Cutting into Monotone Increasing SequenceInsert the fewest commas into a big integer so each piece is at most b, has no leading zero, and the pieces never decrease from left to right.	Medium6	Dynamic programmingString+1	No attempts yet	3s	1024 MB	Judgeable
Heap StructureGiven a min-heap of n nodes, count how many nodes can hold the k-th smallest element.	Medium6	TreeBinary search+1	No attempts yet	3s	1024 MB	Judgeable
NumbersGiven N positive integers, their total sum, and the products of each adjacent pair, find the integers or report that none exist.	Medium6	Number theoryMath+1	No attempts yet	1s	1024 MB	Judgeable
Sum of Product of Binomial CoefficientsGiven N and K, find the sum of f(k) for k from 1 to K modulo 998244353, where f(k) is a sum of nested binomial products.	Medium6	MathCombinatorics	No attempts yet	2s	1024 MB	Judgeable
Strawberries in a BoxGiven a grid of strawberries, find the fewest empty cells to fill so that every strawberry gets a unique pair of row-prefix and column-prefix counts.	Medium6	MatrixPrefix sum+1	No attempts yet	4s	1024 MB	Judgeable
Camp room assignmentFor each n from 1 to m, count the length-2n sequences over m universities in which no university appears more than n times.	Medium6	CombinatoricsMath	No attempts yet	3s	1024 MB	Judgeable
Digit-only subrectanglesGiven a grid of digits and asterisks, sum the squared digit totals of all rectangles that contain only digits, modulo 998244353.	Medium6	Prefix sumMath+1	No attempts yet	3s	1024 MB	Judgeable
Bubble SortGiven range-minimum constraints, find the non-negative integer sequence with the fewest bubble sort swaps (inversions), or report -1 if none exists.	Medium6	GreedySegment tree+1	No attempts yet	2s	1024 MB	Judgeable
K-Divisible GraphGiven a weighted undirected graph and K, decide whether every closed walk has total weight divisible by K.	Medium6	GraphUnion-find+1	No attempts yet	2s	1024 MB	Judgeable
Daegu Science High School BetIan reorders his scores to maximize his total winnings against Yehwan's fixed scores, where a win pays 100, a tie pays 20, and a loss costs 50.	Medium6	SortingGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Daegu Ilgwa Science High SchoolCount monotone lattice paths in d dimensions from (1,...,1) to (N,...,N) that visit P given points in order, modulo 1e9+7.	Medium6	Dynamic programmingCombinatorics	No attempts yet	1s	1024 MB	Judgeable