Problems

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Total results29,197 problems

Forgotten Password
Medium7
Dynamic programming, String+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cow Rescue
Medium7
Graph, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Grand Farm-off
Medium7
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Job Hunt
Medium7
Graph, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bobsledding
Medium7
Greedy, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cheese Towers
Medium7
Dynamic programming, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Covering the Corral
Medium7
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cows on Ice
Medium7
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Slowing down
Medium7
Tree, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Chocolate Eating
Medium7
Binary search, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Toy Shopping
Medium7
Sorting, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Need For Speed
Medium7
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cow Politics
Medium7
Tree, DFS+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Machine Schedule
Medium7
Graph, Union-find+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Watering Plan Check
Medium7
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Baric Bovine
Medium7
Dynamic programming, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Maximum Flow
Medium7
Graph, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pumps and Pipes
Medium7
Dynamic programming, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Leprechaun
Medium7
Array, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Moon Mooing
Medium7
Heap, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Restaurant
Medium7
Dynamic programming, Divide and conquer+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Ski Lessons
Medium7
Dynamic programming, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bovine Embroidery
Medium7
Geometry, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Spreading Out the Cows
Medium7
Dynamic programming, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Random Walk
Medium7
Probability, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Exploration
Medium7
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Summing Sums
Medium7
Math, Matrix+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Bovine Accordion and Banjo Orchestra
Medium7
Dynamic programming, Prefix sum+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cow Jogging
Medium7
Graph, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Crisis on the Farm
Medium7
Brute force, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Corn Fields
Medium7
Dynamic programming, Bit manipulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rooftop Garden Benchmarking
Medium7
Stack, Array+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Fewest Coins
Medium7
Dynamic programming, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Wonderprime Brands
Medium7
Number theory, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Problem Solving
Medium7
Dynamic programming, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Building a New Barn
Medium7
Math, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cow Sorting
Medium7
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Time Planner
Medium7
Intervals, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cow Yahtzee
Medium7
Combinatorics, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Gold Balanced Lineup
Medium7
Hash map, Prefix sum+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dining
Medium7
Graph, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
City Horizon
Medium7
Segment tree, Divide and conquer+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Moving Object Recognition
Medium7
BFS, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Corrupted BST
Medium7
Tree, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
WonderTeam
Medium7
Greedy, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sub-dictionary
Medium7
Graph, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Calculating Taxi Fare
Medium7
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Islands and Bridges
Medium7
Dynamic programming, Bit manipulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Zombie's Treasure Chest
Medium7
Math, Number theory+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Revenge of Fibonacci
Medium7
Math, Binary search+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Palindrome-Free Numbers
Medium7
Dynamic programming, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pipes
Medium7
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Vim
Medium7
Dynamic programming, Greedy+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Solitaire
Medium7
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Left Labyrinths
Medium7
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Family
Medium7
Graph, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Water Treatment Plants
Medium7
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
It's not a Bug, it's a Feature!
Medium7
Graph, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fast Food
Medium7
Dynamic programming, Divide and conquer+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sorting Slides
Medium7
Binary search, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Single-Player Games
Medium7
Probability, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pushing Boxes
Medium7
BFS, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
MBone
Medium7
Graph, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Atlantis
Medium7
Geometry, Segment tree+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cog-Wheels
Medium7
Number theory, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Number Game
Medium7
Game theory, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Slash Maze
Medium7
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dreisam Equations
Medium7
Backtracking, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Formatting Text
Medium7
Dynamic programming, String+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Treasure
Medium7
Divide and conquer, Binary search+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Word
Medium7
String, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Time
Medium7
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Puzzle
Medium7
Backtracking, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Gossiping
Medium7
Simulation, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Robot
Medium7
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Unimodal Palindromic Decompositions
Medium7
Dynamic programming, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dehuff
Medium7
Tree, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Picture Puzzle
Medium7
Backtracking, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Follow My Logic
Medium7
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
To the Max
Medium7
Dynamic programming, Array+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bee on the Honeycomb
Medium7
Geometry, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Single Point of Failure
Medium7
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cog-Wheels
Medium7
Number theory, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Enigma
Medium7
Brute force, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Number Game
Medium7
Game theory, Backtracking+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Eeny Meeny
Medium7
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Roman Numerals
Medium7
Brute force, Backtracking+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Calculator Language
Medium7
Implementation, Recursion+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stamps
Medium7
Dynamic programming, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Making Change
Medium7
Dynamic programming, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Graph Coloring
Medium7
Graph, Backtracking+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Solving a Triangle
Medium7
Geometry, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Peter's Calculator
Medium7
Implementation, Recursion+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Frame Stacking
Medium7
Graph, Topological sort+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Channel Allocation
Medium7
Graph, Backtracking+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Gears on a Board
Medium7
Graph, BFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Another Lottery
Medium7
Probability, Math+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Elias Gamma Code
Medium7
Dynamic programming, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Food Portion Size
Medium7
Math, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
String Decoding
Medium7
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Forgotten PasswordFind the lexicographically smallest length-L string that matches a pattern of known letters and '?' and can be written as a concatenation of given dictionary words.	Medium7	Dynamic programmingString+2	No attempts yet	1s	128 MB	Judgeable
Cow RescueFind the minimum walking time from a start triangle to any exit in a triangular maze with up to a million rows, then break ties by row and column.	Medium7	GraphShortest path+2	No attempts yet	1s	128 MB	Judgeable
The Grand Farm-offGenerate weights and utilities for 3N cows, then choose N cows maximizing total utility while minimizing total weight, and print the weight modulo M.	Medium7	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
Job HuntBessie earns at most D per city visit, travels free paths and paid flights, and can repeat cities; find the maximum total profit or -1 if unbounded.	Medium7	GraphShortest path+2	No attempts yet	1s	128 MB	Judgeable
BobsleddingBessie's speed changes by at most 1 per meter, turn i caps her speed at S_i when she passes marker T_i, and we want the highest speed she can reach anywhere on the course.	Medium7	GreedyImplementation+2	No attempts yet	1s	128 MB	Judgeable
Cheese TowersStack unlimited cheese blocks up to total height T; any block of height at least K crushes everything below it to 4/5 height, maximizing total value.	Medium7	Dynamic programmingGreedy+2	No attempts yet	1s	128 MB	Judgeable
Covering the CorralGiven arcs of given start and length on a circle of circumference C, find the fewest arcs whose union covers the whole circle.	Medium7	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
Cows on IceBessie slides on ice until a rock stops her; find the minimum number of pushes to move from her start cell to the goal cell.	Medium7	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
Slowing downFor each cow in order, count how many pastures already occupied by earlier cows lie on the tree path from node 1 to that cow's pasture.	Medium7	TreeDFS+2	No attempts yet	1s	128 MB	Judgeable
Chocolate EatingSchedule N chocolates, eaten in fixed order over D days, to maximize the smallest bedtime happiness, where happiness halves each night and rises by eaten values.	Medium7	Binary searchGreedy+2	No attempts yet	1s	128 MB	Judgeable
Toy ShoppingSelect three of N toys maximizing the sum of joy/price ratios, and output the total price plus the three indices sorted by ratio.	Medium7	SortingGreedy+1	No attempts yet	1s	128 MB	Judgeable
Need For SpeedGiven a car's base force and mass plus N parts that each add force and mass, choose the subset maximizing total force over total mass, breaking ties by smaller total mass.	Medium7	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
Cow PoliticsGiven a tree with each node belonging to one of K parties, find the diameter (greatest distance between any two nodes) of the nodes in each party.	Medium7	TreeDFS+2	No attempts yet	2s	128 MB	Judgeable
Machine ScheduleGiven jobs each runnable in one of two modes on two machines, minimize the number of mode changes needed to process all jobs.	Medium7	GraphUnion-find+2	No attempts yet	1s	128 MB	Judgeable
Watering Plan CheckDecide whether a grid plan groups every non-scarecrow cell into connected triples with matching letters, then count the fence holes, or print -1.	Medium7	ImplementationSimulation+2	No attempts yet	1s	128 MB	Judgeable
The Baric BovineChoose the smallest subset of N pressure readings so the total interpolation-style error stays within E, and report that size plus the least error for it.	Medium7	Dynamic programmingGreedy+2	No attempts yet	1s	128 MB	Judgeable
Maximum FlowCompute the maximum flow from node A to node Z through a network of pipes with given capacities, using series and parallel reductions.	Medium7	GraphImplementation+2	No attempts yet	1s	128 MB	Judgeable
Pumps and PipesPlace the fewest pumps along a 20 m per pipe water line so pressure stays within limits, choosing the lexicographically smallest position set.	Medium7	Dynamic programmingGreedy+2	No attempts yet	1s	128 MB	Judgeable
The LeprechaunGiven an N x N matrix on a torus, find the contiguous circular run along any row, column, or either diagonal with the largest sum.	Medium7	ArrayDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
Moon MooingStarting from an initial value, repeatedly apply two monotone linear-floor functions to all generated values and report the N-th smallest distinct value.	Medium7	HeapMath+2	No attempts yet	1s	128 MB	Judgeable
RestaurantSplit a sequence of N foods into consecutive groups, where a group costs the square of its number of distinct foods, and minimize the total cost.	Medium7	Dynamic programmingDivide and conquer+2	No attempts yet	1s	128 MB	Judgeable
Ski LessonsGiven ski lessons that overwrite Bessie's skill at fixed start times and slopes with skill and time costs, maximize the number of runs by time T.	Medium7	Dynamic programmingGreedy+2	No attempts yet	1s	128 MB	Judgeable
Bovine EmbroideryGiven N lines and a circle of radius d, count pairs of chords whose intersection point lies within distance d of the origin; lines missing the circle are ignored.	Medium7	GeometrySorting+2	No attempts yet	1s	128 MB	Judgeable
Spreading Out the CowsPlace N cows into S stalls so adjacent gaps are D or D+1 with as many D as possible, minimizing total movement from given start positions.	Medium7	Dynamic programmingGreedy+2	No attempts yet	1s	128 MB	Judgeable
Random WalkParse a small random program with procedures and threshold IF/GOTO or PROC commands, then compute each requested procedure's expected running time to three decimals.	Medium7	ProbabilityGraph+2	No attempts yet	1s	128 MB	Judgeable
ExplorationLandmarks on a number line are visited in order of increasing distance from the origin; find the maximum number she can reach within T minutes.	Medium7	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
Summing SumsEach round every cow replaces her number with the sum of the other cows' numbers mod 98765431; report the values after exactly T rounds.	Medium7	MathMatrix+2	No attempts yet	1s	128 MB	Judgeable
The Bovine Accordion and Banjo OrchestraChoose increasing pairs between two length-N sequences to maximize the sum of A_i*B_j minus the squared sums of each maximal block of unpaired elements on both sides.	Medium7	Dynamic programmingPrefix sum+2	No attempts yet	1s	128 MB	Judgeable
Cow JoggingGiven a DAG with edges pointing from higher to lower numbered nodes, report the K shortest path lengths from node N to node 1, with duplicates allowed.	Medium7	GraphDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
Crisis on the FarmGiven up to 1000 stacks of 30 cows and 1000 haystacks on a grid, choose K whistle moves (all stacks shift together) maximizing cows lifted onto haystacks, then output the lexicographically smallest best sequence.	Medium7	Brute forceSimulation+1	No attempts yet	1s	128 MB	Judgeable
Corn FieldsCount subsets of fertile cells in an M by N grid, M,N at most 12, with no two chosen cells sharing an edge, modulo 100000000.	Medium7	Dynamic programmingBit manipulation+2	No attempts yet	1s	128 MB	Judgeable
Rooftop Garden BenchmarkingCount, over every building, how many strictly shorter buildings stand to its right before a building at least as tall blocks the view.	Medium7	StackArray+2	No attempts yet	1s	128 MB	Judgeable
The Fewest CoinsGiven coin denominations, bounded supplies that John holds, and unlimited shopkeeper change, find the minimum total number of coins exchanged so John pays at least T with exact change returned.	Medium7	Dynamic programmingGreedy+2	No attempts yet	1s	128 MB	Judgeable
Wonderprime BrandsGiven D and N, find the smallest integer at least N whose digit string splits into two primes of length at least D, neither with a leading zero.	Medium7	Number theoryBrute force+2	No attempts yet	1s	128 MB	Judgeable
Problem SolvingGiven a monthly budget M and per-problem advance and completion payments, find the minimum number of months to solve all P problems in order, where each month spends at most the previous month's budget.	Medium7	Dynamic programmingGreedy	No attempts yet	1s	128 MB	Judgeable
Building a New BarnPlace a barn at integer coordinates not used by any cow to minimize the total Manhattan distance to all cows, and count how many such optimal spots exist.	Medium7	MathSorting+2	No attempts yet	1s	128 MB	Judgeable
Cow SortingRearrange a permutation into sorted order by swapping any two elements at a cost equal to their sum, minimizing the total cost.	Medium7	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
Time PlannerGiven each of up to 20 members' busy intervals, output every maximal window of length at least one hour where at most one member is absent throughout.	Medium7	IntervalsSorting+2	No attempts yet	1s	128 MB	Judgeable
Cow YahtzeeCount ordered rolls of N dice with S sides that satisfy at least one OR-ed expression, where each expression ANDs forms like WxR meaning at least W copies of face R.	Medium7	CombinatoricsMath+2	No attempts yet	1s	128 MB	Judgeable
Gold Balanced LineupGiven N cows each with a K-bit feature ID, find the longest contiguous range where every one of the K features appears the same number of times.	Medium7	Hash mapPrefix sum+2	No attempts yet	1s	128 MB	Judgeable
DiningEach cow likes certain foods and drinks, each item can go to one cow; maximize the number of cows that get a liked food and a liked drink.	Medium7	GraphDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
City HorizonGiven N axis-aligned rectangles that all rest on the ground, compute the area of their union.	Medium7	Segment treeDivide and conquer+2	No attempts yet	1s	128 MB	Judgeable
Moving Object RecognitionFind the largest connected white blob in each image, track its centroid over time, and report the average per-second velocity in x and y, each to two decimals.	Medium7	BFSSimulation+2	No attempts yet	1s	128 MB	Judgeable
Corrupted BSTGiven a binary tree with distinct integer keys, find the minimum number of node keys to change so the tree satisfies the BST ordering, keeping its shape fixed.	Medium7	TreeDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
WonderTeamFor each n, find the largest possible rank a team can reach while strictly leading the league in wins, goals scored, and fewest goals conceded in a double round-robin.	Medium7	GreedyMath+2	No attempts yet	1s	128 MB	Judgeable
Sub-dictionaryGiven a dictionary where each word's definition uses only other words, find the smallest self-contained subset of words to teach first so all words become learnable.	Medium7	GraphGreedy+2	No attempts yet	1s	128 MB	Judgeable
Calculating Taxi FareGiven a sequence of streets with lengths and per-kilometer times, compute a passenger's fare between two streets using tiered per-kilometer pricing plus night and traffic surcharges.	Medium7	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Islands and BridgesFind the maximum score of a Hamilton path on a graph where the score adds vertex values, edge products, and triangle products, and count how many paths achieve it.	Medium7	Dynamic programmingBit manipulation+2	No attempts yet	1s	128 MB	Judgeable
Zombie's Treasure ChestGiven a chest capacity and two unlimited gem types with sizes and values, maximize total value of gems that fit.	Medium7	MathNumber theory+2	No attempts yet	1s	128 MB	Judgeable
Revenge of FibonacciFor each of up to 50,000 queries, find the smallest Fibonacci index below 100,000 whose decimal representation starts with the given digit string, or print -1.	Medium7	MathBinary search+2	No attempts yet	5s	128 MB	Judgeable
Palindrome-Free NumbersCount integers in [a, b] whose decimal representation has no palindromic substring of length 2 or more.	Medium7	Dynamic programmingImplementation+2	No attempts yet	1s	128 MB	Judgeable
PipesGiven net volume changes at each vertex of a connected graph, decide whether the flow on every edge is uniquely determined and print those flows if so.	Medium7	GraphDFS+2	No attempts yet	1s	128 MB	Judgeable
VimGiven a string over a-j, find the minimum Vim keypresses (x, h, and f C) to delete every 'e' without touching other characters, starting with the cursor at index 0.	Medium7	Dynamic programmingGreedy+2	No attempts yet	2s	512 MB	Judgeable
SolitaireGiven two placements of four identical pieces on an 8x8 board, decide whether slides and jumps reach the second from the first within 8 moves.	Medium7	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
Left LabyrinthsSimulate a wall-following walker that always keeps its left hand on the wall and report whether it reaches the wider central courtyard.	Medium7	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
FamilyCompute the expected percentage of genes shared by pairs of monsters in a given family graph where each child inherits each gene from one parent at random.	Medium7	GraphDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
Water Treatment PlantsFor each given number of cities NC, count the valid strings of V, <, and > that respect the pipe-sharing rules, where NC can reach 100.	Medium7	Dynamic programmingCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
It's not a Bug, it's a Feature!Each bug state is a bitmask; find the shortest total patch time from all bugs present to no bugs, where patches have presence and absence preconditions.	Medium7	GraphShortest path+2	No attempts yet	1s	128 MB	Judgeable
Fast FoodGiven sorted restaurant positions, choose k of them as depots to minimize the total distance from every restaurant to its nearest depot.	Medium7	Dynamic programmingDivide and conquer+2	No attempts yet	1s	128 MB	Judgeable
Sorting SlidesGiven rectangles and points, print the slide letters whose matching number is the same across every valid one-to-one assignment.	Medium7	Binary searchBrute force+2	No attempts yet	1s	128 MB	Judgeable
Single-Player GamesGiven mutually recursive game-tree definitions, find each identifier's expected score under uniform random play, or report it undefined when the game may never end.	Medium7	ProbabilityMath+2	No attempts yet	1s	128 MB	Judgeable
Pushing BoxesGiven a grid maze with a player, a box, and a target, find the minimum number of pushes to move the box to the target, then the minimum total moves among those solutions.	Medium7	BFSShortest path+2	No attempts yet	1s	128 MB	Judgeable
MBoneSimulate a multicast network of routers and hosts: process join, leave, and send events, propagating each packet along tunnels with TTL thresholds, and report the highest remaining TTL each host receives.	Medium7	GraphSimulation+2	No attempts yet	1s	128 MB	Judgeable
AtlantisGiven up to 100 axis-aligned rectangles, compute the area of their union and print it with two decimals.	Medium7	GeometrySegment tree+2	No attempts yet	1s	128 MB	Judgeable
Cog-WheelsGiven wheel sizes that all divide the smallest, decide for each target ratio a:b whether an unlimited gear train of meshing wheels realizes exactly that ratio.	Medium7	Number theoryMath+2	No attempts yet	1s	128 MB	Judgeable
Number GameGiven the numbers still allowed by previous choices, list every move that leaves the opponent in a losing position, or report that none exists.	Medium7	Game theoryDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
Slash MazeCount the closed loops in a grid of slash and backslash walls and report the longest loop's length, where each cell splits into two triangles.	Medium7	GraphDFS+2	No attempts yet	1s	128 MB	Judgeable
Dreisam EquationsInsert +, -, and * into a number-and-parenthesis equation so it holds under strict left-to-right evaluation, choosing the lexicographically smallest valid string.	Medium7	BacktrackingImplementation+2	No attempts yet	1s	128 MB	Judgeable
Formatting TextBreak a paragraph into lines of fixed width, choosing line breaks to minimize total badness with a lexicographic tie-break on gap widths.	Medium7	Dynamic programmingString+2	No attempts yet	1s	128 MB	Judgeable
TreasureFind all treasure cells on an N x N grid by asking rectangle count queries whose cost grows as the rectangle shrinks.	Medium7	Divide and conquerBinary search+2	No attempts yet	2s	256 MB	Judgeable
WordApply a cyclic cellular rewriting rule s times to a binary word of length n, then print the lexicographically smallest rotation.	Medium7	StringSimulation+2	No attempts yet	1s	128 MB	Judgeable
TimeGiven two valid dates and a period such as 3 months or 2 days, count how many whole periods aligned to unit boundaries fit between them using Gregorian leap year rules.	Medium7	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
PuzzleGiven up to 36 fixed-orientation pieces, each with flat, jut, or cavity edges, decide whether they can tile an n by m rectangle with matching jut-cavity adjacencies.	Medium7	BacktrackingImplementation+2	No attempts yet	1s	128 MB	Judgeable
GossipingGiven bus loops with drivers moving in lockstep, decide whether every driver eventually meets every other driver's news.	Medium7	SimulationMath+2	No attempts yet	1s	128 MB	Judgeable
RobotA circular robot on a grid of tracks must go from a start crossing with a given facing to a target crossing, moving 1 to 3 meters per GO and turning 90 degrees per TURN, each command costing one second; find the minimum time, or -1.	Medium7	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
Unimodal Palindromic DecompositionsCount the number of ways to write N as a sum of a palindromic sequence whose values rise to the middle then fall.	Medium7	Dynamic programmingCombinatorics+2	No attempts yet	1s	128 MB	Judgeable
DehuffGiven a sample string and its full binary encoding, reconstruct the unique prefix-code table for the alphabet, or report several possible tables.	Medium7	TreeDFS+2	No attempts yet	1s	128 MB	Judgeable
Picture PuzzleCount the number of ways to place and rotate nine square pieces into a 3x3 grid so every touching edge pair matches (same letter, one L half and one R half).	Medium7	BacktrackingBrute force+2	No attempts yet	1s	128 MB	Judgeable
Follow My LogicParse ASCII circuit diagrams made of wires, junctions, AND/OR gates, and inversions, then evaluate the output for each given input assignment.	Medium7	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
To the MaxFind the contiguous rectangular subregion of an N by N integer matrix with the largest possible sum and print that sum.	Medium7	Dynamic programmingArray+2	No attempts yet	1s	128 MB	Judgeable
Bee on the HoneycombGiven hexagonal tiling with side s and two points A and B, find the minimum-length path that goes from A to its hexagon center, hops between adjacent centers, then reaches B.	Medium7	GeometryMath+2	No attempts yet	1s	128 MB	Judgeable
Single Point of FailureFor each undirected connected graph, list every articulation point and the number of connected components its removal creates.	Medium7	GraphDFS+2	No attempts yet	1s	128 MB	Judgeable
Cog-WheelsGiven a set of cog sizes where every size is a multiple of the smallest, decide for each ratio a:b whether it can be realized by chaining products of available sizes.	Medium7	Number theoryMath+2	No attempts yet	1s	128 MB	Judgeable
EnigmaGiven a partial Enigma key and plaintext with a few unknowns, complete the decryption of the ciphertext.	Medium7	Brute forceSimulation+2	No attempts yet	1s	128 MB	Judgeable
Number GameGiven the available numbers from 2 to 20 in a Number Game position, list every move that leaves the opponent in a losing position.	Medium7	Game theoryBacktracking+2	No attempts yet	1s	128 MB	Judgeable
Eeny MeenyFor each range of tribe sizes, find the smallest position that survives the 15-syllable counting-out for every size and both directions, or report that none exists.	Medium7	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Roman NumeralsEach line gives a Roman sum A+B=C. Decide whether it holds as a Roman numeral equation, then classify its cryptarithm as impossible, ambiguous, or valid.	Medium7	Brute forceBacktracking+2	No attempts yet	1s	128 MB	Judgeable
Calculator LanguageEvaluate expressions in a tiny language with right-associative equal-precedence operators, assignment, and right-to-left operand evaluation, then report changed variables.	Medium7	ImplementationRecursion+2	No attempts yet	1s	128 MB	Judgeable
StampsFor each h and k with h+k<=9, find k stamp values whose at-most-h sums cover 1..n consecutively for the longest range, then print the lexicographically smallest such set and n.	Medium7	Dynamic programmingBrute force+2	No attempts yet	1s	128 MB	Judgeable
Making ChangeFor each transaction, find the fewest total coins exchanged when you pay with your limited coins and the shopkeeper returns change using unlimited coins.	Medium7	Dynamic programmingGreedy+2	No attempts yet	1s	128 MB	Judgeable
Graph ColoringFor each graph, find a maximum independent set and output one optimal coloring whose sorted black node list is lexicographically smallest.	Medium7	GraphBacktracking+2	No attempts yet	1s	128 MB	Judgeable
Solving a TriangleGiven some sides and angles of a triangle, use the trigonometry identities to determine whether missing values are unique, finite-many, or impossible.	Medium7	GeometryMath+2	No attempts yet	1s	128 MB	Judgeable
Peter's CalculatorParse assignment, PRINT, and RESET statements, evaluate expressions with variables, detect cycles or undefined references, and print values or UNDEF.	Medium7	ImplementationRecursion+2	No attempts yet	1s	128 MB	Judgeable
Frame StackingGiven a picture of several stacked lettered frames on a grid, recover the bottom-to-top stacking order, printing all valid orders alphabetically.	Medium7	GraphTopological sort+2	No attempts yet	1s	128 MB	Judgeable
Channel AllocationGiven a planar graph of up to 26 repeaters, find the chromatic number, the fewest colors needed so adjacent repeaters differ.	Medium7	GraphBacktracking+2	No attempts yet	1s	128 MB	Judgeable
Gears on a BoardDetermine each gear's rotation direction and speed from the motor, propagating through same-level ring contacts, and report overlap or conflicting rotation errors.	Medium7	GraphBFS+2	No attempts yet	1s	128 MB	Judgeable
Another LotteryEach of n players buys tickets across m rounds; round j pays 2^j to one random ticket. For each player, print the reduced fraction for the probability of winning strictly more money than everyone else.	Medium7	ProbabilityMath+2	No attempts yet	1s	256 MB	Judgeable
Elias Gamma CodeGiven counts of numbers by binary bit length, choose prefix shifts and optional leading zeros to minimize the total encoded length.	Medium7	Dynamic programmingGreedy	No attempts yet	1s	128 MB	Judgeable
Food Portion SizeChoose a real portion size S to minimize a(wasted food) + b(number of servings, each student at most 3), and print the optimum as a reduced fraction.	Medium7	MathBrute force+2	No attempts yet	1s	128 MB	Judgeable
String DecodingGiven a string, a permutation, and a large repetition count m, recover the string that the permutation maps to the given encoded string.	Medium7	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable