Problems

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Total results29,431 problems

Quantum Moochanics
Medium7
Simulation, Binary search+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Palindrome Game
Medium7
Game theory, Number theory+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Minimum Sum of Maximums
Medium7
Greedy, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Infinite Adventure
Medium7
Dynamic programming, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Central String
Medium7
String, Brute force+2
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Special Physical Attack
Medium7
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Journey
Medium7
Graph, BFS+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Leaders
Medium7
Greedy, Hash map+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Paintings
Medium7
Greedy, Recursion+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Gummy Candies
Medium7
Dynamic programming, Shortest path
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Very Favorite Sequence
Medium7
Prefix sum, Array+1
No attempts yet
Time limit
6s
Memory limit
1024 MB
Judgeable
Light Bulbs
Medium7
Graph, BFS+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Kraniki
Medium7
Intervals, Stack+1
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Hyundai Mobis Autonomous Driving Testing 1
Medium7
Matrix, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Phoenix and Dalgu
Medium7
Dynamic programming, Prefix sum+1
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Tower
Medium7
Dynamic programming, Greedy+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
It did not run away, it just went where the light is
Medium7
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Antifreeze
Medium7
Tree, Union-find+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Clever Cell Choices
Medium7
Graph, BFS
No attempts yet
Time limit
6s
Memory limit
1024 MB
Judgeable
Harmonic Operations
Medium7
Math, String+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cowreography
Medium7
Greedy, String+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Grass Segments
Medium7
Intervals, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Smaller Averages
Medium7
Dynamic programming, Prefix sum
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Bessie's Interview
Medium7
Heap, Union-find+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Logical Moos
Medium7
Segment tree, String+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Farmer John's Favorite Permutation
Medium7
Greedy, Simulation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Flat Tree Theory
Medium7
Tree, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Hypothermia
Medium7
Graph, BFS+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Broken Calculator
Medium7
Math, Greedy+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Wooden Board
Medium7
Dynamic programming, Probability+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Hanbit Media (Hard)
Medium7
Greedy, Segment tree
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rolling balls
Medium7
Tree, Divide and conquer+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Do You Know Palindrome?
Medium7
String, String matching+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Gauss's Law
Medium7
Geometry, Two pointers+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Security Game
Medium7
Graph, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Tree Kadane
Medium7
Tree, Dynamic programming+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Prime Sequence
Medium7
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fibonacci Souvenirs
Medium7
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Manhattan
Medium7
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rooms
Medium7
Graph, Matrix+1
No attempts yet
Time limit
3.5s
Memory limit
1024 MB
Judgeable
Byeokrok's Masks (Hard)
Medium7
Geometry, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Candy Factory
Medium7
Tree, Simulation+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Fill the Circle
Medium7
Segment tree, Binary search+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Ttangttangba Split
Medium7
Geometry, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
A Duel of Two Proud Geniuses
Medium7
Math, String+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Tree Sudoku
Medium7
Tree, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
AtCoder Study
Medium7
Graph, Shortest path+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Lem0nad3's Bar
Medium7
Dynamic programming, Sorting+1
No attempts yet
Time limit
4s
Memory limit
512 MB
Judgeable
Zoo Management
Medium7
Graph, DFS+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Quartets
Medium7
Simulation, Implementation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Tilting Tiles
Medium7
Matrix, Simulation+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Money Copying
Medium7
Graph, Shortest path+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Pirouettes
Medium7
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
밤양갱
Medium7
String, String matching+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
You Have Talent
Medium7
Dynamic programming, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
AK47
Medium7
Binary search, Bit manipulation+1
No attempts yet
Time limit
4.7s
Memory limit
1024 MB
Judgeable
Naruto vs Sasuke
Medium7
Game theory, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Minimum String Extraction
Medium7
Greedy, String+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hyundai Mobis Truck Platooning
Medium7
Graph, Shortest path+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Nice Connected Components and Queries
Medium7
Union-find, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Magic Bean
Medium7
Simulation, Implementation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Return Pickup
Medium7
Dynamic programming, Intervals
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ascending Order
Medium7
Greedy, Array+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Jobs
Medium7
Tree, Greedy+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Portal
Medium7
Number theory, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Trains
Medium7
Dynamic programming, Prefix sum
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Flooding Wall
Medium7
Sorting, Prefix sum+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Tycho
Medium7
Dynamic programming, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
CERN
Medium7
Array, Hash map+2
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Choreography
Medium7
Array, Math+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Counting Increasing Subsequences of G
Medium7
Dynamic programming, Prefix sum+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
ESC and Queries
Medium7
Math, Matrix+1
No attempts yet
Time limit
0.2s
Memory limit
1024 MB
Judgeable
Cramming Schedule
Medium7
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
List Virtualization
Medium7
Tree, Prefix sum+1
No attempts yet
Time limit
6s
Memory limit
1024 MB
Judgeable
Cache Memory Placement
Medium7
Segment tree, Array
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Avoiding an Arrrgument
Medium7
Game theory, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Of the Children
Medium7
Graph, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Copy and Paste
Medium7
Combinatorics, Dynamic programming+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Doubling
Medium7
String, Dynamic programming+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Pedometer Proxy Service
Medium7
Greedy, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Ainta, Binta, and Cinta
Medium7
Graph, Hash map
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Toy
Medium7
Graph, BFS+1
No attempts yet
Time limit
1.35s
Memory limit
1024 MB
Judgeable
Billiards
Medium7
Geometry, Math+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
All Survived?
Medium7
Dynamic programming, Probability+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Storing Eggs
Medium7
Binary search, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Increase the Toll Fees
Medium7
Minimum spanning tree, Union-find+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Gathering Colors
Medium7
Graph, Implementation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Tree Extraction
Medium7
Tree, Simulation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
XOR Maximum
Medium7
String, Bit manipulation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Maximize The Value
Medium7
Segment tree, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Contingency Plan 2
Medium7
Dynamic programming, Tree+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Count BFS Graph
Medium7
Graph, BFS+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Deck-Building Game
Medium7
Bit manipulation, Combinatorics+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Triangle Construction
Medium7
Greedy, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Slime Synthesis
Medium7
Dynamic programming, Intervals+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Partitioning a Sequence by Score
Medium7
Dynamic programming, Prefix sum+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Physics Experiment
Medium7
Math, Number theory+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Island Bridges Puzzle
Medium7
Backtracking, Graph+1
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Springfield
Medium7
Union-find, Intervals+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Team Coding
Medium7
Tree, DFS+2
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Quantum MoochanicsGiven alternating mootrinos and antimootrinos on a line that reverse direction at each observation, find the observation number when each particle disappears.	Medium7	SimulationBinary search+1	No attempts yet	2s	1024 MB	Judgeable
Palindrome GameCows take turns removing a positive palindrome number of stones from a pile of S (up to 10^(10^5)). Decide who wins with optimal play.	Medium7	Game theoryNumber theory+1	No attempts yet	2s	1024 MB	Judgeable
Minimum Sum of MaximumsGiven a line of tiles with some fixed positions, the task is to permute the free tiles to minimize the sum of pairwise maximums of adjacent tiles.	Medium7	GreedySorting+1	No attempts yet	2s	1024 MB	Judgeable
Infinite AdventureGiven portals whose cycle times are powers of 2, find the city reached after Delta portal hops from city v starting on day t.	Medium7	Dynamic programmingMath	No attempts yet	2s	1024 MB	Judgeable
Central StringGiven N strings of equal length L and a bound D, the task is to find a string within Hamming distance D of every input string, or report that none exists.	Medium7	StringBrute force+2	No attempts yet	3s	1024 MB	Judgeable
Special Physical AttackPick a set of non-adjacent students to shave so that the cheapest way to punish a cover of the line costs the most, then print that cost.	Medium7	Dynamic programmingArray	No attempts yet	1s	1024 MB	Judgeable
JourneyGiven a connected graph and some recorded shortest-path distances from an unknown city (-1 means unrecorded), find every city where the hotel could be.	Medium7	GraphBFS+1	No attempts yet	2s	1024 MB	Judgeable
LeadersSplit a sequence of integers into the fewest subsequences so that each one has a leader, an element occurring more than half the time.	Medium7	GreedyHash map+1	No attempts yet	3s	1024 MB	Judgeable
PaintingsFind the fewest non-overlapping squares, from n sizes where each size divides the next, that exactly cover an h by w wall, or report -1 if it cannot.	Medium7	GreedyRecursion+1	No attempts yet	2s	1024 MB	Judgeable
Gummy CandiesPick candies so every color appears equally often, and find the minimum cost for each total weight remainder modulo m.	Medium7	Dynamic programmingShortest path	No attempts yet	3s	1024 MB	Judgeable
Very Favorite SequenceGiven an array, count index triples i<j<k in the sequence of all contiguous subarray sums (ordered by start, then end) whose values sum to zero.	Medium7	Prefix sumArray+1	No attempts yet	6s	1024 MB	Judgeable
Light BulbsCount the on/off bulb patterns reachable from the initial state when each switch flips its pair of bulbs only if both bulbs match, modulo 1e9+7.	Medium7	GraphBFS+1	No attempts yet	3s	1024 MB	Judgeable
KranikiGiven n shelves at heights 1 to n, each with endpoints l_i and r_i, find the expected number of taps opened over a random order, modulo 1e9+7.	Medium7	IntervalsStack+1	No attempts yet	4s	1024 MB	Judgeable
Hyundai Mobis Autonomous Driving Testing 1Find the fewest moves for a car to cross a 2-row track made of a sample repeated K times, or report -1 if no path exists.	Medium7	MatrixDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Phoenix and DalguDalgu blocks one K by K square avoiding the two corners, and the task is to find the largest-weight monotone path from (1,1) to (N,N) under the best such block.	Medium7	Dynamic programmingPrefix sum+1	No attempts yet	1.5s	1024 MB	Judgeable
TowerGiven blocked step ranges on a staircase, single steps costing A seconds and D-step jumps costing B seconds, find the minimum time to reach each queried step X.	Medium7	Dynamic programmingGreedy+1	No attempts yet	2s	1024 MB	Judgeable
It did not run away, it just went where the light isCount the integers from 1 to p^q - 1 that repeatedly rounded-divide by p and stop with output r, modulo 1,000,000,009.	Medium7	MathNumber theory+1	No attempts yet	1s	1024 MB	Judgeable
AntifreezeGiven a weighted tree with heater rooms, answer whether two heater rooms can be linked by a chain of heater rooms where every gap is at most T.	Medium7	TreeUnion-find+1	No attempts yet	2s	1024 MB	Judgeable
Clever Cell ChoicesCount the empty cells where the first player, placing the opening stone there, wins the game of alternately placing stones on side-adjacent empty cells.	Medium7	GraphBFS	No attempts yet	6s	1024 MB	Judgeable
Harmonic OperationsCount the contiguous sublists of K operations (reverse, rotate left, rotate right) that map the string S back to itself.	Medium7	MathString+1	No attempts yet	1s	1024 MB	Judgeable
CowreographyGiven two binary strings with equal counts of ones, find the fewest swaps of positions at most K apart that turn the first string into the last.	Medium7	GreedyString+1	No attempts yet	2s	1024 MB	Judgeable
Grass SegmentsGiven N intervals, each with a minimum overlap k_i, count for each interval how many other intervals overlap it by at least k_i.	Medium7	IntervalsSorting+1	No attempts yet	2s	1024 MB	Judgeable
Smaller AveragesCount the ways to split two length-N arrays into the same number of contiguous parts, where each a-part's average is at most its paired b-part's average, mod 1e9+7.	Medium7	Dynamic programmingPrefix sum	No attempts yet	2s	1024 MB	Judgeable
Bessie's InterviewGiven K farmers and N cows with interview durations, find when cow N+1 starts her interview and which farmers could interview her.	Medium7	HeapUnion-find+1	No attempts yet	2s	1024 MB	Judgeable
Logical MoosGiven a boolean and/or statement, each query asks whether replacing keywords l through r with one true or false can make the whole statement equal a target value.	Medium7	Segment treeString+1	No attempts yet	2s	1024 MB	Judgeable
Farmer John's Favorite PermutationGiven the hints written while a permutation is taken apart from its ends, find the lexicographically smallest matching permutation or print -1.	Medium7	GreedySimulation+1	No attempts yet	2s	1024 MB	Judgeable
Flat Tree TheoryGiven a weighted tree, find the minimum number of path operations, each subtracting 1 from every edge on a chosen path, needed to bring all edge weights to 0.	Medium7	TreeDynamic programming+1	No attempts yet	2s	1024 MB	Judgeable
HypothermiaGiven an N by M grid of normal and hypothermic people, count those who stay at normal temperature forever when at most K can fall ill each night.	Medium7	GraphBFS+1	No attempts yet	2s	1024 MB	Judgeable
Broken CalculatorGiven N, find the fewest clicks of +4, -4, *4, or /4 (division only when the number is divisible by 4) needed to reach N from 0.	Medium7	MathGreedy+1	No attempts yet	2s	1024 MB	Judgeable
Wooden BoardGiven N trees with daily growth chances in percent, find the expected area of the largest rectangle under the tree heights after M days, modulo 998244353.	Medium7	Dynamic programmingProbability+1	No attempts yet	5s	1024 MB	Judgeable
Hanbit Media (Hard)Given a stream of insertions and deletions of book prices, report the minimum number of pages where each page holds prices whose maximum is less than twice the minimum.	Medium7	GreedySegment tree	No attempts yet	1s	1024 MB	Judgeable
Rolling ballsGiven depth N and Q ball numbers, find the vertex where each ball stops when balls roll down a perfect binary tree under the balancing rules.	Medium7	TreeDivide and conquer+1	No attempts yet	1s	1024 MB	Judgeable
Do You Know Palindrome?Given a string S of up to 10^6 lowercase letters, count the palindromic substrings that contain the x-th character for each query.	Medium7	StringString matching+1	No attempts yet	1s	1024 MB	Judgeable
Gauss's LawGiven a convex polygon and point charges, remove at most one vertex to maximize the absolute sum of charges strictly inside the polygon.	Medium7	GeometryTwo pointers+1	No attempts yet	1s	1024 MB	Judgeable
Security GameFor each B, find the maximum total protections where each robot covers at most B buildings and each building has between L and U robots, or -1 if impossible.	Medium7	GraphImplementation	No attempts yet	2s	512 MB	Judgeable
Tree KadaneGiven a weighted tree with point updates, find the maximum sum over all connected subsets after each update.	Medium7	TreeDynamic programming+1	No attempts yet	3s	1024 MB	Judgeable
Prime SequenceBuild a length-N sequence of distinct primes up to 1,000,000 where every contiguous window of length K has a sum divisible by K.	Medium7	MathNumber theory+1	No attempts yet	1s	1024 MB	Judgeable
Fibonacci SouvenirsSplit the Fibonacci numbers F_1 to F_N into two groups with equal sums, using as many numbers as possible, and print both groups.	Medium7	MathGreedy	No attempts yet	1s	1024 MB	Judgeable
ManhattanCount the distinct lattice paths that start in zone Z1 and end in zone Z2 for two non-overlapping rectangles, modulo 666013.	Medium7	CombinatoricsMath	No attempts yet	1s	1024 MB	Judgeable
RoomsGiven a letter grid, count the same-letter 4-connected regions that have at least one cell inside each query rectangle.	Medium7	GraphMatrix+1	No attempts yet	3.5s	1024 MB	Judgeable
Byeokrok's Masks (Hard)Count the 4-point subsets of N given points (no three collinear) whose convex hull is a quadrilateral.	Medium7	GeometrySorting+1	No attempts yet	2s	1024 MB	Judgeable
Candy FactoryGiven two belts of candies, apply Q rotations, prefix swaps of length R, and gripper resizes, then print both belts' final contents.	Medium7	TreeSimulation+1	No attempts yet	0.5s	1024 MB	Judgeable
Fill the CircleEach number from 2 to N goes into the x-th empty slot clockwise from a reference number's slot on a circle, and the task is to print the circle starting at 1.	Medium7	Segment treeBinary search+1	No attempts yet	2s	512 MB	Judgeable
Ttangttangba SplitChoose a line ax=by through the origin so that Junseong's share is maximized, given that Seongu takes the heavier side including treasures on the line.	Medium7	GeometrySorting+1	No attempts yet	1s	1024 MB	Judgeable
A Duel of Two Proud GeniusesGiven A in base u and B in base v, each with up to 3,000,000 digits of equal length, decide whether A is larger, B is larger, or they are equal.	Medium7	MathString+1	No attempts yet	0.5s	1024 MB	Judgeable
Tree SudokuAssign each vertex of a tree a distinct value from sequence A so that all adjacent-pair sums are pairwise distinct, or report NO.	Medium7	TreeGreedy+1	No attempts yet	1s	1024 MB	Judgeable
AtCoder StudySeunghyeong starts at building N in a row of 2N-1 buildings and must collect M scattered Gunsu using steps of 1 or N, with free returns to visited buildings. The task asks for the minimum time.	Medium7	GraphShortest path+1	No attempts yet	1s	512 MB	Judgeable
Lem0nad3's BarChoose at most K lemonades and the times to drink them so that the total of each fizz level times a drink-order weight is maximized.	Medium7	Dynamic programmingSorting+1	No attempts yet	4s	512 MB	Judgeable
Zoo ManagementDecide whether animals can move along tunnels, in simultaneous cycles, from their starting enclosures to the target arrangement.	Medium7	GraphDFS+1	No attempts yet	5s	1024 MB	Judgeable
QuartetsGiven a log of Quartets moves, decide whether some initial card deal makes every move legal, and if not, find the first move after which cheating is certain.	Medium7	SimulationImplementation+1	No attempts yet	2s	1024 MB	Judgeable
Tilting TilesGiven a start and an end grid of colored tiles, decide whether tilting the grid in four directions can turn the start into the end.	Medium7	MatrixSimulation+1	No attempts yet	3s	1024 MB	Judgeable
Money CopyingGiven barter trades between items and won, find the minimum starting money that lets a holder grow money without bound, or INF if none exists.	Medium7	GraphShortest path+1	No attempts yet	2s	1024 MB	Judgeable
PirouettesCount the ways to place K obstacles on the 2N free cells of a room so that a ballerina starting at 0 and taking T unit steps is back at 0.	Medium7	Dynamic programmingCombinatorics+1	No attempts yet	1s	1024 MB	Judgeable
밤양갱Find the fewest seconds to type 'daldidalgo' N times then 'daldidan', using single-letter appends or pasting a substring already typed.	Medium7	StringString matching+1	No attempts yet	1s	1024 MB	Judgeable
You Have TalentGiven N win values, M loss values, and a protection interval K, find the highest score Minseok can reach after all N+M games.	Medium7	Dynamic programmingGreedy+1	No attempts yet	1s	1024 MB	Judgeable
AK47Find the two treasure zones among N zones in a row using at most 47 range queries, where a query reacts only when exactly one treasure lies in the range.	Medium7	Binary searchBit manipulation+1	No attempts yet	4.7s	1024 MB	Judgeable
Naruto vs SasukeNaruto and Sasuke alternate attack or heal moves from given health and powers; output who wins, or DRAW if neither can force a win.	Medium7	Game theoryMath	No attempts yet	1s	1024 MB	Judgeable
Minimum String ExtractionGiven an N by M grid of lowercase letters, hide exactly K columns and read the remaining cells row by row to find the lexicographically smallest string.	Medium7	GreedyString+1	No attempts yet	1s	1024 MB	Judgeable
Hyundai Mobis Truck PlatooningGiven a road graph, find the minimum total cost for N-1 trucks sent from city 1 along shortest paths, where a truck following another on the same road pays 90 percent.	Medium7	GraphShortest path+1	No attempts yet	1s	1024 MB	Judgeable
Nice Connected Components and QueriesProcess edge additions, whole-component color flips, and queries for the nice component with the most vertices of a given color, printing its smallest vertex.	Medium7	Union-findGraph+1	No attempts yet	1s	1024 MB	Judgeable
Magic BeanGiven a scrambled Magic Bean with 30 beads on three outer circles and a center circle, output at most 240 rotations that restore the solved state.	Medium7	SimulationImplementation	No attempts yet	2s	2048 MB	Judgeable
Return PickupFind the minimum time for a truck starting at position 0 to collect every house's item after its release time and return to 0.	Medium7	Dynamic programmingIntervals	No attempts yet	1s	1024 MB	Judgeable
Ascending OrderGiven a sequence of positive integers, each query asks for the fewest doublings of elements in a subarray needed to make that subarray non-decreasing.	Medium7	GreedyArray+1	No attempts yet	1s	1024 MB	Judgeable
JobsGiven N jobs with profits and prerequisite jobs, find the maximum profit from choosing and ordering jobs when you start with s euros and money must never go negative.	Medium7	TreeGreedy+1	No attempts yet	2s	1024 MB	Judgeable
PortalGiven N portal cells on an infinite grid, find the maximum number of colours that keeps the friend from noticing the teleports, or -1 if the count is unlimited.	Medium7	Number theoryMath	No attempts yet	2s	1024 MB	Judgeable
TrainsCount the journeys from city 1 where a train from city i stops every d_i cities, at most x_i times, without passing city N. Print the count modulo 10^9+7.	Medium7	Dynamic programmingPrefix sum	No attempts yet	2s	1024 MB	Judgeable
Flooding WallEach of N wall segments has one of two candidate heights, so sum the water trapped over all 2^N walls, modulo 1e9+7.	Medium7	SortingPrefix sum+1	No attempts yet	5s	1024 MB	Judgeable
TychoFind the minimum damage for Tycho to travel from 0 to b, where each second costs 1 and each pulse at multiples of p costs d unless Tycho is sheltered.	Medium7	Dynamic programmingMath+1	No attempts yet	2s	1024 MB	Judgeable
CERNFor each range of particles, count the types that can survive as the last remaining type after colliding pairs of different types.	Medium7	ArrayHash map+2	No attempts yet	4s	1024 MB	Judgeable
ChoreographyDetermine a hidden permutation of 1 to 1000 using only queries that report whether the inversion count in a range is odd.	Medium7	ArrayMath+1	No attempts yet	8s	1024 MB	Judgeable
Counting Increasing Subsequences of GCount increasing subsequences of the Golomb sequence with length N that end at value M, modulo 998244353, for N and M up to 300,000.	Medium7	Dynamic programmingPrefix sum+1	No attempts yet	3s	1024 MB	Judgeable
ESC and QueriesFor each query i j k, the task is to sum the coefficients a, b, and c of the n-th derivative of e^x sin x cos x over n = kx for x from i to j, modulo 1e9+7.	Medium7	MathMatrix+1	No attempts yet	0.2s	1024 MB	Judgeable
Cramming ScheduleGiven exam deadlines, credits, and the study hours needed for each grade, find the highest credit-weighted grade point average when only one subject can be studied at a time.	Medium7	Dynamic programmingSorting+1	No attempts yet	1s	1024 MB	Judgeable
List VirtualizationInsert and delete rectangles in a vertical stack of heights, then count the rectangles whose interiors overlap the band from t to b below the top.	Medium7	TreePrefix sum+1	No attempts yet	6s	1024 MB	Judgeable
Cache Memory PlacementPick one contiguous subarray of A to load into cache, paying K per element, to minimize the total time of all uses given the counts B.	Medium7	Segment treeArray	No attempts yet	2s	1024 MB	Judgeable
Avoiding an ArrrgumentGiven gem values per kind, find the first kind to pick in a snake-order draft where each crewman takes two different kinds, maximizing your guaranteed total.	Medium7	Game theoryDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Of the ChildrenGiven per-city donations and travel costs between cities, find the least initial money at city 0 so the traveler can reach city N-1 without running short on any leg.	Medium7	GraphDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Copy and PasteFind the dictionary-order position of name A among all file names reachable from [0] within K copy and paste rounds, modulo 998244353.	Medium7	CombinatoricsDynamic programming+1	No attempts yet	3s	1024 MB	Judgeable
DoublingGiven pairs (s, c) where typing c after s doubles the message, find the fewest appends and deletes needed to build string T from empty.	Medium7	StringDynamic programming+1	No attempts yet	3s	1024 MB	Judgeable
Pedometer Proxy ServiceFind the minimum distance to pick up each customer's phone from its locker, move at least D m before returning it, and walk back to the office.	Medium7	GreedySorting+1	No attempts yet	2s	1024 MB	Judgeable
Ainta, Binta, and CintaAinta overwrites cells of B and C with values from A so that both sorted, deduplicated sequences match, maximizing their length k and printing one such sequence.	Medium7	GraphHash map	No attempts yet	1.5s	1024 MB	Judgeable
ToyDecide whether the horizontal and vertical parts can slide around obstacles until both overlap on the target cell.	Medium7	GraphBFS+1	No attempts yet	1.35s	1024 MB	Judgeable
BilliardsGiven a billiard table with balls and a coin, find every ball that, struck at 45 degrees, reaches the coin after cushion bounces before hitting another ball or a corner hole.	Medium7	GeometryMath+1	No attempts yet	8s	1024 MB	Judgeable
All Survived?Given each player's team and hit probability, choose targets to maximize the chance that no ally is popped before the game ends.	Medium7	Dynamic programmingProbability+1	No attempts yet	8s	1024 MB	Judgeable
Storing EggsPlace K eggs in usable cells of a 3 by N carton so the closest pair of eggs is as far apart as possible, or report -1 if K eggs cannot fit.	Medium7	Binary searchDynamic programming+1	No attempts yet	2s	1024 MB	Judgeable
Increase the Toll FeesGiven a weighted graph with a unique minimum spanning tree, find the least total increase in tree edge prices so that no original tree edge stays in the new MST, or report -1.	Medium7	Minimum spanning treeUnion-find+1	No attempts yet	2s	1024 MB	Judgeable
Gathering ColorsGiven N boxes with two balls each and one empty box, find the minimum number of moves so that both balls of every color end up in the same box.	Medium7	GraphImplementation+1	No attempts yet	2s	1024 MB	Judgeable
Tree ExtractionGiven a rooted tree with distinct weights, repeatedly shift weights along the min-child path to a leaf, remove that leaf, and print vertex 1's weight before each step.	Medium7	TreeSimulation	No attempts yet	2s	1024 MB	Judgeable
XOR MaximumGiven a binary string, find the largest XOR of the binary values of two of its substrings, which may overlap or be equal.	Medium7	StringBit manipulation+1	No attempts yet	2s	1024 MB	Judgeable
Maximize The ValueFor each position K and operation range [S, T], find the largest sum of X over a contiguous block of operations l to r, counting only operations whose range covers K.	Medium7	Segment treePrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
Contingency Plan 2Given a tree of N computers, add the fewest directed cables so that the resulting network has exactly one topological order.	Medium7	Dynamic programmingTree+1	No attempts yet	2s	1024 MB	Judgeable
Count BFS GraphCount the simple undirected graphs on N nodes whose BFS from node 1 visits the nodes in the given order A, modulo 998244353.	Medium7	GraphBFS+2	No attempts yet	2s	1024 MB	Judgeable
Deck-Building GameCount the ways to pick up to two disjoint decks from N cards so both decks have the same XOR, modulo 998244353.	Medium7	Bit manipulationCombinatorics+1	No attempts yet	2s	1024 MB	Judgeable
Triangle ConstructionGiven a regular polygon whose sides carry A_i equally spaced points, find the most non-crossing, non-degenerate triangles with disjoint corners.	Medium7	GreedyMath+1	No attempts yet	2s	1024 MB	Judgeable
Slime SynthesisGiven a row of slimes with digit levels, merge adjacent pairs of equal level into one slime of level plus one, and find the maximum number of merges possible.	Medium7	Dynamic programmingIntervals+1	No attempts yet	8s	1024 MB	Judgeable
Partitioning a Sequence by ScoreSplit the sequence into contiguous parts and find the k-th largest total of the squared part sums over all partitions.	Medium7	Dynamic programmingPrefix sum+1	No attempts yet	8s	1024 MB	Judgeable
Physics ExperimentFind a start coordinate x0 and speed v for a wave bouncing in a length-m machine that match all shuffled position and direction records.	Medium7	MathNumber theory+1	No attempts yet	8s	1024 MB	Judgeable
Island Bridges PuzzleDraw bridges between numbered islands on a grid so each island has exactly its number of bridges and all islands form one connected group.	Medium7	BacktrackingGraph+1	No attempts yet	Not set	1024 MB	Judgeable
SpringfieldEach machine holds a union of integer ranges. Process merge commands and report how many distinct flavors a given machine holds.	Medium7	Union-findIntervals+1	No attempts yet	3s	1024 MB	Judgeable
Team CodingPick a team lead in a rooted tree so that, after swaps between same-depth employees, the most people share the lead's language, and count the minimum swaps.	Medium7	TreeDFS+2	No attempts yet	4s	1024 MB	Judgeable