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Mediums from real onsites

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Total results3,617 problems

Sasa's Four-Dimensional Candy Bag
Medium5
Prefix sum, Binary search+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
More dogs are better
Medium5
BFS, Array+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Kickboard Commute to School
Medium5
Binary search, Greedy
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
String Game
Medium5
Dynamic programming, String
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Region Coloring
Medium5
Greedy, Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Prize Draw
Medium5
Dynamic programming, Matrix+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Attention
Medium5
Dynamic programming, Segment tree
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Rocket Launching
Medium5
Sorting, Binary search+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Milk Sum
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Asking for Money
Medium5
Graph, DFS+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Empty Squares
Medium5
Dynamic programming, Greedy
No attempts yet
Time limit
0.1s
Memory limit
1024 MB
Judgeable
Thanos Hates Josephus
Medium5
Dynamic programming, Simulation
No attempts yet
Time limit
0.1s
Memory limit
512 MB
Judgeable
I Am Knowledge
Medium5
Greedy, Sorting
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Stairs to the Kimbap Heaven
Medium5
BFS, Shortest path
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
PSAT Special Course
Medium5
BFS, Shortest path+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Rectangular Pizza
Medium5
Sorting, Two pointers+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Demon King's Castle
Medium5
Union-find, Sorting+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Strange Array
Medium5
Array, Hash map+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tree Climbing
Medium5
Dynamic programming, Tree+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Meeting place 2
Medium5
String, Implementation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
prlong longf
Medium5
Dynamic programming, String matching
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Recruiting New SCCC Members
Medium5
Greedy, Graph
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Was the 2022 APC really that hard?
Medium5
Dynamic programming, Prefix sum
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
K-Won Banknotes
Medium5
Shortest path, Graph
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
You Never Learned Geometry and Vectors?
Medium5
Hash map, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Red, Red, Blue, Blue! Sweet Cotton Candy!
Medium5
Array, Greedy+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Allergen Testing
Medium5
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Repetitive String Invention
Medium5
Dynamic programming, String
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Item Collection
Medium5
Binary search, Prefix sum+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Magic with Cards
Medium5
BFS, Graph+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Turn Off the Classroom Lights
Medium5
Dynamic programming, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hungry (Hard)
Medium5
Bit manipulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Yawned-Zoned
Medium5
Dynamic programming, BFS+1
No attempts yet
Time limit
2.5s
Memory limit
1024 MB
Judgeable
Hacking
Medium5
Graph, BFS+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Waiting for Regrading
Medium5
Backtracking, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Wall Value
Medium5
BFS, Graph+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Ant Nest by the Lake
Medium5
Dynamic programming
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Lottery Games
Medium5
Combinatorics, Probability+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Strange Draft
Medium5
Sliding window, Queue+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
K-ary Huffman Encoding
Medium5
Greedy, Heap
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
XOR Necklace
Medium5
Dynamic programming, Bit manipulation
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Algospot Design School
Medium5
Graph, DFS
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ice Cream Machines
Medium5
Greedy, Simulation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Cosmic Commute
Medium5
BFS, Graph+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
German Conference for Public Counting
Medium5
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Investigating Frog Behaviour on Lily Pad Patterns
Medium5
Segment tree, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Loop Invariant
Medium5
String, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bank Counter
Medium5
Greedy, Heap+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rectangle Division
Medium5
Math, Number theory
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fibonacci product
Medium5
Backtracking, Recursion+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Beautiful Sequences
Medium5
Dynamic programming, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Loyalty Game
Medium5
Union-find, Simulation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Calculating Scores
Medium5
Tree, DFS+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Making Sticks
Medium5
Dynamic programming, Number theory+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bullet Hell Game
Medium5
Math, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Mahjong Tenpai
Medium5
Brute force, Backtracking+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Spell Cards
Medium5
Dynamic programming, Intervals+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Burgers
Medium5
Binary search, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Topical
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Leaf Cleanup
Medium5
Sorting, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Citadel Hierarchy
Medium5
Tree, DFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rick's Robe
Medium5
BFS, Graph+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Let's Split Up!
Medium5
Binary search, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Interesting celebrations
Medium5
Dynamic programming, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Code Plagiarism
Medium5
Greedy, Two pointers+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
There Are n Chairs
Medium5
Sorting, Binary search+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Terrifying Palindrome
Medium5
String, Hash map+1
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Alarms
Medium5
Dynamic programming, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Inflation
Medium5
Hash map, Implementation
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Biomarkers
Medium5
Greedy, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Lifesaving Riddle
Medium5
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Electronic Lock
Medium5
Dynamic programming, Greedy
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Counting Operations
Medium5
Tree, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Corrupted Password
Medium5
Greedy, String+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Sorting an Array
Medium5
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Wildcard Parentheses String
Medium5
String, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
They
Medium5
Prefix sum, Two pointers+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Sounds from the Basement
Medium5
Game theory, String
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Chaotic Performance
Medium5
Greedy, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Deadly Mathematics
Medium5
BFS, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Wedding
Medium5
Bit manipulation, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Mafia Estate
Medium5
Greedy, Binary search+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
High-speed transport
Medium5
Math, Combinatorics
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Six-Digit Documents
Medium5
Array, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
The Ancient Runic Lock
Medium5
BFS, Shortest path+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Crossword for a Droid
Medium5
Union-find, Sorting+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Superagent Dish
Medium5
Graph, DFS+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Eating Rats
Medium5
Prefix sum, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Painting
Medium5
Segment tree, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Ralph and Arithmetic
Medium5
Dynamic programming, Math
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Drone Elimination
Medium5
Greedy, Sorting
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Magic Castle
Medium5
Dynamic programming, Tree+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Minefield
Medium5
Array, Binary search+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Optimal rearrangement
Medium5
Array, Prefix sum
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Weakening the Fleet
Medium5
Sorting, Binary search+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Report
Medium5
Binary search, Greedy+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Accounts
Medium5
String, Trie+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
AliKingspress
Medium5
Dynamic programming, Array
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Bad Multitasking
Medium5
Simulation, Greedy+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Rick's Matrix
Medium5
Union-find, Matrix+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Sasa's Four-Dimensional Candy BagFor each child, find how many of Sasa's candy grabs from the sequence A are needed to reach B_i candies, or report that the child is sent away.	Medium5	Prefix sumBinary search+1	No attempts yet	2s	1024 MB	Judgeable
More dogs are betterGiven N, spell amounts A and B, and forbidden count intervals that reset the dog count to zero, find the fewest casts that reach exactly N dogs.	Medium5	BFSArray+1	No attempts yet	2s	1024 MB	Judgeable
Kickboard Commute to SchoolFind the smallest battery capacity that lets Geondeok reach school at position L from home at 0 while visiting at most K charging stations.	Medium5	Binary searchGreedy	No attempts yet	1s	512 MB	Judgeable
String GameGiven a board of N letters and a word of length M, find the most word letters Geondeok can match by stepping left or right one cell at a time.	Medium5	Dynamic programmingString	No attempts yet	2s	512 MB	Judgeable
Region ColoringGiven a grid of 0, 1, and 2 cells, find the fewest horizontal strokes that reproduce the picture, where strokes may overpaint but never cover a 0 cell.	Medium5	GreedyArray	No attempts yet	1s	512 MB	Judgeable
Prize DrawGiven a board with nails, find the bottom column where a ball most likely ends up when it restarts from the top each time it gets stuck.	Medium5	Dynamic programmingMatrix+1	No attempts yet	1s	512 MB	Judgeable
AttentionCount the ingredient triples whose positions increase in both recipe books, or report that no such triple exists.	Medium5	Dynamic programmingSegment tree	No attempts yet	1s	512 MB	Judgeable
Rocket LaunchingGiven buildings at distances X_i with heights H_i, find for each query T the highest altitude Taro can be at by time T after climbing one ladder.	Medium5	SortingBinary search+1	No attempts yet	2s	1024 MB	Judgeable
Milk SumEach query sets one cow's milk rate to j, and the task is to find the maximum total milk over all unhooking orders.	Medium5	GreedySorting+2	No attempts yet	4s	1024 MB	Judgeable
Asking for MoneyGiven who each person asks for money, find every person whose two requests can both fail because those people already paid someone else.	Medium5	GraphDFS+1	No attempts yet	0.5s	1024 MB	Judgeable
Empty SquaresGiven N, the placed tile size K, and E empty squares to its left, find how many squares stay empty after Nico covers as many as possible with the other tiles.	Medium5	Dynamic programmingGreedy	No attempts yet	0.1s	1024 MB	Judgeable
Thanos Hates JosephusFind the last squirrel left when each round keeps the first squirrel, removes the next K-1 clockwise, and the first moves to the right, for N and K up to 10^6.	Medium5	Dynamic programmingSimulation	No attempts yet	0.1s	512 MB	Judgeable
I Am KnowledgeGiven books with a start cost a_i and a finish reward b_i, decide whether some reading order keeps joy from going negative.	Medium5	GreedySorting	No attempts yet	2s	1024 MB	Judgeable
Stairs to the Kimbap HeavenGiven N and K, decide whether Minhee can reach stair N in exactly K actions when tapping stair i moves Minhee to stair i + floor(i/2).	Medium5	BFSShortest path	No attempts yet	1s	512 MB	Judgeable
PSAT Special CourseGiven a graph with one letter per vertex, find the lexicographically smallest string along a shortest path from an S-stamped vertex to an E-stamped vertex.	Medium5	BFSShortest path+2	No attempts yet	2s	512 MB	Judgeable
Rectangular PizzaGiven the cut positions on a W by H pizza, count the slices whose area is at most K.	Medium5	SortingTwo pointers+1	No attempts yet	1s	1024 MB	Judgeable
The Demon King's CastleFor each plot, find the total tax of the connected region of plots no higher than it that contains that plot, with the plot as the castle.	Medium5	Union-findSorting+1	No attempts yet	3s	1024 MB	Judgeable
Strange ArrayGiven an array, determine whether every element lying between two equal values is at most that value.	Medium5	ArrayHash map+1	No attempts yet	1s	1024 MB	Judgeable
Tree ClimbingCount the root-to-leaf paths where each jump from vertex i goes down to a descendant at distance 1 to A_i, modulo 998244353.	Medium5	Dynamic programmingTree+1	No attempts yet	1s	1024 MB	Judgeable
Meeting place 2Given a string S of length N, find the K-th lexicographically smallest string that differs from S in at most one position, or print -1 if there is none.	Medium5	StringImplementation+1	No attempts yet	2s	1024 MB	Judgeable
prlong longfCount the original strings that become the given string when every "int" is replaced with "longlong".	Medium5	Dynamic programmingString matching	No attempts yet	2s	1024 MB	Judgeable
Recruiting New SCCC MembersAssign applicants in descending score order to K groups of capacity X, accepting each one only if all accepted applicants can still be seated, moving earlier ones if needed.	Medium5	GreedyGraph	No attempts yet	2s	1024 MB	Judgeable
Was the 2022 APC really that hard?Count the sequences of N difficulties where each D_i lies in [a_i, b_i] and adjacent values differ by at most K, modulo 1e9+7.	Medium5	Dynamic programmingPrefix sum	No attempts yet	1s	1024 MB	Judgeable
K-Won BanknotesFind the cheapest route from city S to city T on a directed road graph whose total fee is a multiple of K, or report IMPOSSIBLE.	Medium5	Shortest pathGraph	No attempts yet	2s	1024 MB	Judgeable
You Never Learned Geometry and Vectors?Count the pairs of 2D integer vectors whose dot product is zero, where a zero vector counts as perpendicular to every other vector.	Medium5	Hash mapMath	No attempts yet	2s	1024 MB	Judgeable
Red, Red, Blue, Blue! Sweet Cotton Candy!For each interval [l, r], find two R positions followed by two B positions in order inside it, or report -1 if none exist.	Medium5	ArrayGreedy+1	No attempts yet	2s	1024 MB	Judgeable
Allergen TestingGiven n compounds and d days, find the fewest sites needed to identify the one allergen for up to 10^4 queries with n and d up to 10^18.	Medium5	MathImplementation	No attempts yet	1s	2048 MB	Judgeable
Repetitive String InventionCount the ways to pick two non-overlapping substrings, in order, whose concatenation is a repetitive string (a square) for a string of length up to 800.	Medium5	Dynamic programmingString	No attempts yet	2s	2048 MB	Judgeable
Item CollectionGiven N weighted boxes on a grid and Q axis-parallel moves from (1, 1), find the total items collected along the path.	Medium5	Binary searchPrefix sum+1	No attempts yet	3s	1024 MB	Judgeable
Magic with CardsGiven a deck of 2n cards, find the fewest riffle and scuffle shuffles that move the card at position i to position j, or report -1.	Medium5	BFSGraph+1	No attempts yet	2s	1024 MB	Judgeable
Turn Off the Classroom LightsFind the least time for Jinseo to visit every lit classroom from floor 1 and return to a staircase there, using the fewest stairs first.	Medium5	Dynamic programmingImplementation	No attempts yet	1s	1024 MB	Judgeable
Hungry (Hard)For each m up to 10^18, find the pair x <= y whose 2^x + 2^y is closest to m (smallest on ties), and print x and y.	Medium5	Bit manipulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Yawned-ZonedPlace exactly W dividers between columns so the largest group of students who yawn from one starting student is as small as possible, then print that size.	Medium5	Dynamic programmingBFS+1	No attempts yet	2.5s	1024 MB	Judgeable
HackingPick X computers to hack at time 0 to maximize total money before security reaches them, or print -1 if an uninfectable computer earns money.	Medium5	GraphBFS+2	No attempts yet	2s	1024 MB	Judgeable
Waiting for RegradingGiven an answer key and an OMR sheet, find the most matches after at most K pull or shift operations on the sheet.	Medium5	BacktrackingSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Wall ValueGiven a grid with walls, N pieces, and a destination, find the sum of shortest distances and the total drop in that sum when each wall is removed.	Medium5	BFSGraph+1	No attempts yet	2s	512 MB	Judgeable
Ant Nest by the LakePlace ants on a circle of N rooms, each with C_i side chambers, so no two directly connected occupied places touch. Find the maximum number of ants.	Medium5	Dynamic programming	No attempts yet	2s	1024 MB	Judgeable
Lottery GamesGiven several lottery tickets, find which ticket gives the highest chance of matching at least K numbers, listing all tied tickets in order.	Medium5	CombinatoricsProbability+1	No attempts yet	1s	1024 MB	Judgeable
Strange DraftFor each test case, find the K consecutive players whose best defensive ability at each of the nine positions sums to the largest total.	Medium5	Sliding windowQueue+1	No attempts yet	1s	1024 MB	Judgeable
K-ary Huffman EncodingGiven N character frequencies, find the minimum total length of a K-ary prefix-free encoding of the weighted string.	Medium5	GreedyHeap	No attempts yet	1s	1024 MB	Judgeable
XOR NecklaceGiven a necklace of N beads, remove some beads to maximize the sum of XORs between each pair of adjacent beads around the cycle.	Medium5	Dynamic programmingBit manipulation	No attempts yet	3s	1024 MB	Judgeable
Algospot Design SchoolGiven rectangles for drawings on the front and back of a sheet, find the maximum number of drawings you can cut out as separate pieces.	Medium5	GraphDFS	No attempts yet	1s	1024 MB	Judgeable
Ice Cream MachinesGiven a queue of flavour requests and k machines, find the fewest machine cleanings needed to serve every customer in order.	Medium5	GreedySimulation+1	No attempts yet	2s	1024 MB	Judgeable
Cosmic CommuteFind the expected minimum number of light trains from planet 1 to planet n when one random wormhole teleport is allowed.	Medium5	BFSGraph+1	No attempts yet	3s	1024 MB	Judgeable
German Conference for Public CountingGiven n, find the fewest digit signs needed so every number from n down to 0 can be displayed with them.	Medium5	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Investigating Frog Behaviour on Lily Pad PatternsFrogs sit on sorted lily pads and each jump lands on the nearest empty pad to the right. Output the landing pad for every recorded jump.	Medium5	Segment treeSimulation	No attempts yet	1s	1024 MB	Judgeable
Loop InvariantGiven a balanced parentheses string read as a circle, find a cyclic rotation that is balanced and differs from the original, or print no.	Medium5	StringPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Bank CounterGiven N people, each with a deadline T_i and a job time P_i, find the maximum number who can finish their jobs when served one at a time.	Medium5	GreedyHeap+1	No attempts yet	1s	1024 MB	Judgeable
Rectangle DivisionGiven a board of size a by b, k cuts, and m rectangles, find the horizontal and vertical cut counts h and v, preferring fewer horizontal cuts, or print -1.	Medium5	MathNumber theory	No attempts yet	1s	1024 MB	Judgeable
Fibonacci productGiven n, count the ways to write it as a product of Fibonacci numbers greater than 1, where order does not matter.	Medium5	BacktrackingRecursion+1	No attempts yet	1s	1024 MB	Judgeable
Beautiful SequencesCount length-n sequences from the set A (values 1 to 8) where any two equal values x are more than x positions apart, modulo 1e9+7.	Medium5	Dynamic programmingBit manipulation	No attempts yet	1s	1024 MB	Judgeable
Loyalty GameEach type 1 query pours x liters from student i onward, with each student drinking up to their capacity, and type 2 asks a student's total drunk amount.	Medium5	Union-findSimulation+1	No attempts yet	2s	1024 MB	Judgeable
Calculating ScoresGiven a tree with node scores, answer each query for node v's total score when node r is the root, which is the sum of scores in v's subtree.	Medium5	TreeDFS+1	No attempts yet	2s	1024 MB	Judgeable
Making SticksFor each query length L, count the ways to reach L from some base stick A by multiplying by a sequence of integers k of at least 2.	Medium5	Dynamic programmingNumber theory+1	No attempts yet	1s	1024 MB	Judgeable
Bullet Hell GameDecide whether a character on an N by M grid can dodge bullets that chase it in 8 directions for T seconds, moving first each second.	Medium5	MathSimulation	No attempts yet	1s	1024 MB	Judgeable
Mahjong TenpaiGiven 13 mahjong tiles, check whether the hand is in tenpai and list every tile kind that completes a valid 14-tile win.	Medium5	Brute forceBacktracking+1	No attempts yet	2s	1024 MB	Judgeable
Spell CardsGiven N cards with mana costs, merge adjacent pairs where each merge costs the sum and leaves the larger value. Find the minimum total cost.	Medium5	Dynamic programmingIntervals+1	No attempts yet	1s	1024 MB	Judgeable
BurgersGiven stock x_i and the per-ingredient needs a_i and b_i of two burger recipes, find the maximum number of burgers that can be made.	Medium5	Binary searchMath+1	No attempts yet	1s	1024 MB	Judgeable
TopicalGiven knowledge requirements and gains for n modules across k topics, find the maximum number of modules Benson can complete in some order.	Medium5	GreedySorting+1	No attempts yet	1s	1024 MB	Judgeable
Leaf CleanupGiven n pile sizes, choose a range of k consecutive integers within 1 to c that minimizes the total size of the piles falling inside it.	Medium5	SortingPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Citadel HierarchyGiven a rooted tree of Ricks with Mortys as leaves, decide whether each Rick can reorder its direct subordinates so the bottom-level Mortys end up sorted.	Medium5	TreeDFS+1	No attempts yet	1s	1024 MB	Judgeable
Rick's RobeGiven a graph with wet vertices and existing holes, find the vertex for a new hole that minimizes the time for every wet point to reach its nearest hole.	Medium5	BFSGraph+1	No attempts yet	3s	1024 MB	Judgeable
Let's Split Up!Split n people into two groups, each with one leader and one room, to minimize the largest danger akb, and print the minimum with the assignment.	Medium5	Binary searchMath+1	No attempts yet	1s	1024 MB	Judgeable
Interesting celebrationsCount the subsequences of string s that equal one of the words seq_1 to seq_26, modulo 998244353.	Medium5	Dynamic programmingString	No attempts yet	1s	1024 MB	Judgeable
Code PlagiarismGiven strings s and t, decide whether t can remain after repeatedly deleting any two adjacent characters from s.	Medium5	GreedyTwo pointers+1	No attempts yet	1s	1024 MB	Judgeable
There Are n ChairsPick chairs whose total width reaches H so that the largest height gap between neighbors in the row is as small as possible.	Medium5	SortingBinary search+1	No attempts yet	1s	1024 MB	Judgeable
Terrifying PalindromeOrder n equal-length strings so their concatenation is a palindrome, or report -1 if no such order exists.	Medium5	StringHash map+1	No attempts yet	1.5s	1024 MB	Judgeable
AlarmsGiven three alarms and N required wake-up times, find the fewest taps needed to move one alarm per day so that each required time has a ringing alarm.	Medium5	Dynamic programmingImplementation	No attempts yet	2s	1024 MB	Judgeable
InflationGiven N dish prices, apply Q events (add x to every price, or set each price equal to x to y) and print the price sum after each event.	Medium5	Hash mapImplementation	No attempts yet	3s	1024 MB	Judgeable
BiomarkersGiven a decimal string n, delete some digits to get the largest number divisible by 3 without leading zeros, or print 0 if none exists.	Medium5	GreedyString	No attempts yet	1s	1024 MB	Judgeable
The Lifesaving RiddleFor each shift x from 1 to n-1, decide whether some array a can produce the given difference array b under a left cyclic shift.	Medium5	MathNumber theory+1	No attempts yet	1s	1024 MB	Judgeable
Electronic LockFind the largest integer without leading zeros that uses exactly n lit segments, with digits drawn only from the given set.	Medium5	Dynamic programmingGreedy	No attempts yet	2s	1024 MB	Judgeable
Counting OperationsGiven a rooted tree with integers on its vertices, find the fewest +1 or -1 root-path operations that make every vertex zero.	Medium5	TreeMath	No attempts yet	2s	1024 MB	Judgeable
Corrupted PasswordGiven strings s and t, find a position x and a character c different from s_x so that replacing s_x with c makes s a subsequence of t.	Medium5	GreedyString+1	No attempts yet	2s	1024 MB	Judgeable
Sorting an ArrayGiven an array of up to 8 values and swap operations with costs, find the minimum total cost to sort the array, or -1 if impossible.	Medium5	Shortest pathGraph+1	No attempts yet	1s	1024 MB	Judgeable
Wildcard Parentheses StringGiven a string of '(', ')', '?', and '', decide whether the '?' and '' can be filled in to form a correct bracket string.	Medium5	StringGreedy	No attempts yet	1s	1024 MB	Judgeable
TheyGiven n points with child counts, pick a prefix ending at l and a suffix starting at r (l < r) so that the two sums differ by as little as possible.	Medium5	Prefix sumTwo pointers+1	No attempts yet	2s	1024 MB	Judgeable
Sounds from the BasementGiven a strip of R and B cells, decide whether the first player wins the game of cutting strips whose end colors differ.	Medium5	Game theoryString	No attempts yet	2s	1024 MB	Judgeable
Chaotic PerformanceGiven viewer decency levels and police intervals, lower the levels by a total of at most k to minimize the sum of each viewer's coverage times its level.	Medium5	GreedyPrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
Deadly MathematicsGiven two natural numbers a and b, find the fewest actions that replace one of them with its rounded geometric or quadratic mean until they are equal.	Medium5	BFSMath	No attempts yet	2s	1024 MB	Judgeable
WeddingAfter each arrival, departure, or XOR dance, the task is to print the total sociability of the fairies currently present.	Medium5	Bit manipulationImplementation	No attempts yet	2s	1024 MB	Judgeable
Mafia EstateSplit the estate into n contiguous segments, each containing one son's mansion, so that the longest segment is as short as possible.	Medium5	GreedyBinary search+1	No attempts yet	2s	1024 MB	Judgeable
High-speed transportCount the ways to pick new Maglev and Hyperloop ranges inside and around the old ones that keep total length and do not overlap.	Medium5	MathCombinatorics	No attempts yet	1s	1024 MB	Judgeable
Six-Digit DocumentsGiven n six-digit identifiers, find the cyclic shift that minimizes the total number of inversions summed over all six digit positions.	Medium5	ArrayPrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
The Ancient Runic LockFind the shortest walk from S that touches the k stones in the given order and then reaches F, or report -1 if it is impossible.	Medium5	BFSShortest path+1	No attempts yet	2s	1024 MB	Judgeable
Crossword for a DroidFill the free cells with digits so every horizontal and vertical word is a palindrome, minimizing the total digit change from the original grid.	Medium5	Union-findSorting+1	No attempts yet	2s	1024 MB	Judgeable
Superagent DishGiven ingredients that can be bought, made from others, or both, find the minimum store cost to make the dish, or -1 if impossible.	Medium5	GraphDFS+1	No attempts yet	2s	1024 MB	Judgeable
Eating RatsGiven a protocol of 1s and 2s that splits into two eaters with k each, find the largest lead Kratos could have over Atreus at any moment.	Medium5	Prefix sumDynamic programming+1	No attempts yet	2s	1024 MB	Judgeable
PaintingAfter each flip on a checkerboard grid, report the fewest cells to recolor so that black cells form a top block and white cells form the rest.	Medium5	Segment treePrefix sum+1	No attempts yet	2s	1024 MB	Judgeable
Ralph and ArithmeticCount the integers from 1 to n (n up to 10^18) whose decimal digits avoid every digit in a given set of minor digits.	Medium5	Dynamic programmingMath	No attempts yet	2s	1024 MB	Judgeable
Drone EliminationGiven n drone positions, find a shooting order so that no drone reaches the origin when drones move one step in any of 8 directions after each shot, or report -1.	Medium5	GreedySorting	No attempts yet	2s	1024 MB	Judgeable
Magic CastleGiven a triangulation of a regular n-gon, find the minimum number of diagonals to remove so that every triangle loses at least one side.	Medium5	Dynamic programmingTree+1	No attempts yet	2s	1024 MB	Judgeable
MinefieldEvery cell starts with a mine. Process digs and find the nearest remaining mine above, below, left, or right of a given cell.	Medium5	ArrayBinary search+1	No attempts yet	2s	1024 MB	Judgeable
Optimal rearrangementGiven a permutation, pick a value x and regroup fish into strengths below x, exactly x, and above x, keeping order within groups. Find the minimum number of inversions.	Medium5	ArrayPrefix sum	No attempts yet	4s	1024 MB	Judgeable
Weakening the FleetGiven n ship powers, output the powers in removal order, where each step removes a ship whose power equals the lower median of the remaining ships.	Medium5	SortingBinary search+1	No attempts yet	2s	1024 MB	Judgeable
ReportSplit two word lists by a vertical line on a w-wide roll so the greedy line-wrapping needs the fewest rows, then print that row count.	Medium5	Binary searchGreedy+1	No attempts yet	2s	1024 MB	Judgeable
AccountsPair 2n strings into n couples so that in each couple one string is a prefix of the other, and print the indices of each couple.	Medium5	StringTrie+1	No attempts yet	2s	1024 MB	Judgeable
AliKingspressGiven daily point values a_1 to a_n that repeat after day n, find the fewest days needed to collect exactly x points, or -1 if impossible.	Medium5	Dynamic programmingArray	No attempts yet	2s	1024 MB	Judgeable
Bad MultitaskingEach second the first queued task runs up to b operations, then goes to the back if unfinished. Find the second when the first task (a1) finishes.	Medium5	SimulationGreedy+1	No attempts yet	2s	1024 MB	Judgeable
Rick's MatrixGiven an n by m matrix, find the fewest cells to change so that every row and every column reads the same forwards and backwards.	Medium5	Union-findMatrix+1	No attempts yet	2s	1024 MB	Judgeable