Problems

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Total results29,453 problems

Barber Shop Queue
Medium5
Binary search, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Infinite House of Pancakes (Small)
Medium5
Brute force, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Infinite House of Pancakes (Large)
Medium5
Brute force, Greedy
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Quaternion Dijkstra
Medium5
Simulation, Brute force+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Filling a board with N-ominoes (Small)
Medium5
Geometry, Game theory+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Dreary Design
Medium5
Combinatorics, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Googlander (Small)
Medium5
Backtracking, Simulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Cube IV (Large)
Medium5
Dynamic programming, Graph+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Taking the Metro (Large)
Medium5
Shortest path, Graph
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Broken Calculator (Small)
Medium5
Dynamic programming, Recursion+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Password Attacker (Large)
Medium5
Combinatorics, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Parentheses Order (Small)
Medium5
Dynamic programming, Combinatorics
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Parentheses Order (Large)
Medium5
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Broken Seven-segment Display
Medium5
Brute force, Bit manipulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Broken Seven-segment Display
Medium5
Brute force, Bit manipulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Cut Tiles (Small)
Medium5
Greedy, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Checkerboard Matrix (Small)
Medium5
Matrix, Greedy
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Up and Down Sequence
Medium5
Brute force, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Up and Down (Large)
Medium5
Greedy, Prefix sum
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Trie Sharding (Small)
Medium5
Brute force, Trie+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Part Elf (Large)
Medium5
Number theory, Math+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
The Repeater
Medium5
String, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
The Repeater (Large)
Medium5
String, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Full Binary Tree
Medium5
Tree, Dynamic programming+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Proper Shuffle (Small)
Medium5
Probability, Array+1
No attempts yet
Time limit
60s
Memory limit
512 MB
Judgeable
Cookie Farms
Medium5
Greedy, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Hex Board State
Medium5
Graph, BFS+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Dragon Maze (Small)
Medium5
BFS, Shortest path+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Dragon Maze (Large)
Medium5
BFS, Dynamic programming
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Spaceship Defence (Small)
Medium5
Shortest path, Graph
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Graduation Requirements (Small)
Medium5
Brute force, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Rural Planning (Small)
Medium5
Brute force, Geometry
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Rural Planning
Medium5
Geometry, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Consonants (Large)
Medium5
String, Combinatorics
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
The Great Wall (Small)
Medium5
Simulation, Intervals+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Osmos (Small)
Medium5
Greedy, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Osmos (Large)
Medium5
Greedy, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Bullseye
Medium5
Binary search, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Bullseye
Medium5
Math, Binary search
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Manage Your Energy
Medium5
Greedy, Simulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Arithmetic Digit Numbers 2
Medium5
Backtracking, Combinatorics+1
No attempts yet
Time limit
0.5s
Memory limit
512 MB
Judgeable
Zombie Smash (Small)
Medium5
Brute force, Intervals+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Havannah (Small)
Medium5
Union-find, BFS
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Diamond Inheritance (Large)
Medium5
Graph, Topological sort+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Safety in Numbers
Medium5
Math, Binary search+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Equal Subset Sums (Small)
Medium5
Brute force, Hash map
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Equal Sums
Medium5
Brute force, Hash map+1
No attempts yet
Time limit
20s
Memory limit
512 MB
Judgeable
Password Problem (Large)
Medium5
Probability, Prefix sum+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Kingdom Rush
Medium5
Greedy, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Kingdom Rush (Large)
Medium5
Greedy, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Recycled Numbers (Large)
Medium5
String, Brute force+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Gem Match Cascade
Medium5
Simulation, Brute force+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Technology Planning
Medium5
Topological sort, Graph
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Technology Planning
Medium5
Topological sort, Graph+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Survivor (Small)
Medium5
Backtracking, Dynamic programming
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Han River (Small)
Medium5
Number theory, Brute force
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
New Calendar (Large)
Medium5
Math, Simulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Choosing a meeting place (Large)
Medium5
Shortest path, Graph
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Infinite Garden (Small)
Medium5
BFS, Simulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Card Shuffle (Large)
Medium5
Simulation, Intervals
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Best coffee (Small)
Medium5
Greedy, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Morning Coffee (Large)
Medium5
Greedy, Heap+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Bit Count (Small)
Medium5
Bit manipulation, Dynamic programming
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Bit Count (Large)
Medium5
Bit manipulation, Greedy
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Theme Park (Large)
Medium5
Simulation, Queue+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Irregular Cakes (Small)
Medium5
Binary search, Geometry
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Irregular Cakes (Large Input)
Medium5
Geometry, Binary search+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Dire Straights (Small)
Medium5
Backtracking, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Airport Walkways (Small)
Medium5
Greedy, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Space Emergency (Small)
Medium5
Brute force, Simulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
FreeCell Statistics
Medium5
Number theory, Brute force
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
FreeCell Statistics (Large)
Medium5
Number theory, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
The Killer Word (Small)
Medium5
Simulation, String+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Candy Splitting
Medium5
Bit manipulation, Greedy
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Candy Splitting (Large)
Medium5
Bit manipulation, Greedy
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Music Collection Search
Medium5
String matching, Brute force+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Irregular Expressions (Large)
Medium5
Brute force, String+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Vanishing Numbers (Small)
Medium5
Math, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Closing the Loop (Large)
Medium5
Greedy, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Building a House (Small)
Medium5
Stack, Matrix
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Making Chess Boards (Small)
Medium5
Simulation, Brute force
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Picking Up Chicks (Small)
Medium5
Greedy, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Picking Up Chicks
Medium5
Greedy, Array
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Snapper Chain (Large)
Medium5
Bit manipulation, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Fair Warning (Small)
Medium5
Number theory, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Theme Park Roller Coaster
Medium5
Queue, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Get to Work (Small)
Medium5
Greedy, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Get to Work (Large)
Medium5
Greedy, Implementation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Doubly-sorted grid (small)
Medium5
Backtracking, Dynamic programming
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Lights (Small Input)
Medium5
Geometry, Implementation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Crazy Rows (Small)
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Crazy Rows (Large)
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Decision Tree (Large)
Medium5
String, Recursion+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Square Math (Small)
Medium5
BFS, Brute force+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Crossing the Road (Small)
Medium5
Shortest path, Graph+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Watersheds (Large)
Medium5
Graph, DFS+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Counting welcome to code jam subsequences
Medium5
Dynamic programming, String
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Juice (Small Input)
Medium5
Brute force, Geometry+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Scaled Triangle (Small)
Medium5
Geometry, Math+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
What are Birds? (Small)
Medium5
Intervals, Implementation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Barber Shop QueueFind which of B barbers with different cutting times serves the Nth customer when ties go to the smallest barber number.	Medium5	Binary searchMath	No attempts yet	5s	512 MB	Judgeable
Infinite House of Pancakes (Small)Diners eat one pancake per minute in parallel while special minutes split a pile instead of eating, so find the fewest minutes to clear all piles.	Medium5	Brute forceMath	No attempts yet	5s	512 MB	Judgeable
Infinite House of Pancakes (Large)Decide how many times to split pancake stacks so the splits plus the tallest final stack is minimized.	Medium5	Brute forceGreedy	No attempts yet	5s	512 MB	Judgeable
Quaternion DijkstraDecide whether a repeated i/j/k string splits into three nonempty parts reducing to i, j, and k under quaternion multiplication.	Medium5	SimulationBrute force+1	No attempts yet	5s	512 MB	Judgeable
Filling a board with N-ominoes (Small)Given polyomino size X and board size R by C, decide whether the first player can choose a shape that makes the board impossible to tile.	Medium5	GeometryGame theory+1	No attempts yet	5s	512 MB	Judgeable
Dreary DesignCount RGB triples with components from 0 to K whose largest pairwise difference is at most V.	Medium5	CombinatoricsMath	No attempts yet	5s	512 MB	Judgeable
Googlander (Small)Count all distinct walks on an R by C grid where the walker moves straight or turns right and follows forced moves until both moves are blocked.	Medium5	BacktrackingSimulation	No attempts yet	5s	512 MB	Judgeable
Cube IV (Large)Find the longest run of consecutive room numbers placed in neighboring cells and report its starting number and length.	Medium5	Dynamic programmingGraph+1	No attempts yet	5s	512 MB	Judgeable
Taking the Metro (Large)Find the fastest route between two metro stations where each boarding adds a line waiting time and transfers use walking tunnels.	Medium5	Shortest pathGraph	No attempts yet	5s	512 MB	Judgeable
Broken Calculator (Small)Split X into factors typed with working digits only, minimizing the total of digit, multiply, and equals presses.	Medium5	Dynamic programmingRecursion+1	No attempts yet	5s	512 MB	Judgeable
Password Attacker (Large)Count length-N strings over M symbols that use every symbol at least once, modulo 1e9+7.	Medium5	CombinatoricsMath	No attempts yet	5s	512 MB	Judgeable
Parentheses Order (Small)Print the k-th valid parentheses string of n pairs in lexicographic order for each test case, or report that it does not exist.	Medium5	Dynamic programmingCombinatorics	No attempts yet	5s	512 MB	Judgeable
Parentheses Order (Large)Given n and k, output the k-th valid parentheses string of n pairs in lexicographic order, or Doesn't Exist! when fewer than k exist.	Medium5	Dynamic programmingCombinatorics+1	No attempts yet	5s	512 MB	Judgeable
Broken Seven-segment DisplayFrom N consecutive seven-segment readings with unknown start digit and dead segments, infer the next reading, or print ERROR when consistent readings disagree.	Medium5	Brute forceBit manipulation	No attempts yet	5s	512 MB	Judgeable
Broken Seven-segment DisplayFrom N recorded seven-segment states of a countdown with unknown start digit and stuck-off segments, find the single possible next state or report ERROR!.	Medium5	Brute forceBit manipulation+1	No attempts yet	5s	512 MB	Judgeable
Cut Tiles (Small)Find the fewest M by M tiles that yield all required power-of-two squares when cut without joining pieces.	Medium5	GreedyMath	No attempts yet	5s	512 MB	Judgeable
Checkerboard Matrix (Small)Find the fewest row and column swaps that turn a binary 2N by 2N matrix into an alternating checkerboard, or report IMPOSSIBLE.	Medium5	MatrixGreedy	No attempts yet	5s	512 MB	Judgeable
Up and Down SequenceCount the fewest adjacent swaps that turn distinct numbers into a sequence that rises to one peak and then falls.	Medium5	Brute forceSorting	No attempts yet	5s	512 MB	Judgeable
Up and Down (Large)Find the fewest adjacent swaps that turn the sequence into one that rises to a peak and then falls.	Medium5	GreedyPrefix sum	No attempts yet	5s	512 MB	Judgeable
Trie Sharding (Small)Split up to 8 strings across labeled servers to maximize the summed trie node counts and count the optimal splits.	Medium5	Brute forceTrie+1	No attempts yet	5s	512 MB	Judgeable
Part Elf (Large)Given a claimed elf fraction P/Q, decide whether 40 generations of averaging can produce it and report the closest possible generation of a full elf ancestor.	Medium5	Number theoryMath+1	No attempts yet	5s	512 MB	Judgeable
The RepeaterEqualize N lowercase strings using only adjacent duplicate insertions and deletions with the fewest moves, or report impossibility.	Medium5	StringSorting+1	No attempts yet	5s	512 MB	Judgeable
The Repeater (Large)Decide whether N lowercase strings can be made identical by duplicating or deleting adjacent equal letters, and report the fewest moves.	Medium5	StringSorting+1	No attempts yet	5s	512 MB	Judgeable
Full Binary TreeGiven a tree with up to 15 nodes, delete as few nodes as possible so the remaining nodes form a full binary tree for some choice of root.	Medium5	TreeDynamic programming+1	No attempts yet	5s	512 MB	Judgeable
Proper Shuffle (Small)Given a permutation of 1000 numbers, decide whether it came from the uniform shuffle (GOOD) or the biased shuffle (BAD) by using probability.	Medium5	ProbabilityArray+1	No attempts yet	60s	512 MB	Judgeable
Cookie FarmsStarting at 2 cookies per second, decide how many farms that cost C and add F each to buy before waiting until X cookies are held.	Medium5	GreedyMath	No attempts yet	5s	512 MB	Judgeable
Hex Board StateGiven each Hex board with red and blue stones, decide whether the position is unreachable, won by red, won by blue, or still open.	Medium5	GraphBFS+2	No attempts yet	5s	512 MB	Judgeable
Dragon Maze (Small)Find the fewest-step walk from the entrance to the exit of a cell grid and report the most power gathered on such a route.	Medium5	BFSShortest path+1	No attempts yet	5s	512 MB	Judgeable
Dragon Maze (Large)In a grid with blocked cells, walk from the entrance to the exit in the fewest moves and collect the most power among such walks.	Medium5	BFSDynamic programming	No attempts yet	5s	512 MB	Judgeable
Spaceship Defence (Small)Soldiers cross rooms with free jumps between same-color rooms and timed one-way turbolifts, and each query asks for the fastest trip time.	Medium5	Shortest pathGraph	No attempts yet	5s	512 MB	Judgeable
Graduation Requirements (Small)Find the longest clockwise drive around a traffic circle that never meets or head-on crosses any observed car.	Medium5	Brute forceSimulation+1	No attempts yet	5s	512 MB	Judgeable
Rural Planning (Small)Order all given points into a simple polygon whose area exceeds half the largest achievable area and print the lexicographically smallest such order.	Medium5	Brute forceGeometry	No attempts yet	5s	512 MB	Judgeable
Rural PlanningArrange every post into a simple polygon larger than half the convex hull area by building the two specified hull-chain orders and keeping the larger one.	Medium5	GeometrySorting+1	No attempts yet	5s	512 MB	Judgeable
Consonants (Large)Count the substrings of each given name that contain at least n consecutive consonants.	Medium5	StringCombinatorics	No attempts yet	5s	512 MB	Judgeable
The Great Wall (Small)Count the interval attacks that breach a wall which rises to each successful attack's strength, judging attacks on the same day against the unchanged wall.	Medium5	SimulationIntervals+1	No attempts yet	5s	512 MB	Judgeable
Osmos (Small)Starting from size A, sort the other motes and absorb each smaller one, adding helper motes or deleting blockers for the fewest operations.	Medium5	GreedySorting	No attempts yet	5s	512 MB	Judgeable
Osmos (Large)Starting from size A, absorb the sorted motes in order and use the fewest added or removed motes to clear each blocker.	Medium5	GreedySorting	No attempts yet	5s	512 MB	Judgeable
BullseyeStarting from a white circle of radius r, count how many alternating 1cm black rings the paint budget can complete.	Medium5	Binary searchMath	No attempts yet	5s	512 MB	Judgeable
BullseyeMaria starts from inner radius r with t millilitres of paint and paints alternating 1 cm black and white rings; find how many full black rings fit.	Medium5	MathBinary search	No attempts yet	5s	512 MB	Judgeable
Manage Your EnergyAllocate a capped energy reserve that recharges after each activity across fixed-order tasks to maximize value times energy spent.	Medium5	GreedySimulation	No attempts yet	5s	512 MB	Judgeable
Arithmetic Digit Numbers 2Count the integers from 1 to N, with N up to 10^18, whose decimal digits form an arithmetic sequence.	Medium5	BacktrackingCombinatorics+1	No attempts yet	0.5s	512 MB	Judgeable
Zombie Smash (Small)Plan a route from (0, 0) that smashes the most zombies, each catchable for 1000 ms after it appears, with 8-direction moves and a 750 ms smasher recharge.	Medium5	Brute forceIntervals+1	No attempts yet	5s	512 MB	Judgeable
Havannah (Small)The program places the given stones in order on a hexagonal board and reports the first move that completes a ring, bridge, or fork.	Medium5	Union-findBFS	No attempts yet	5s	512 MB	Judgeable
Diamond Inheritance (Large)Decide whether any pair of classes in each inheritance DAG has two different inheritance paths between them.	Medium5	GraphTopological sort+1	No attempts yet	5s	512 MB	Judgeable
Safety in NumbersCompute for each contestant the smallest vote percentage that guarantees another contestant ties or trails them no matter how the remaining votes split.	Medium5	MathBinary search+1	No attempts yet	5s	512 MB	Judgeable
Equal Subset Sums (Small)For each set of 20 distinct numbers, print two different non-empty subsets with equal sum in code order, or Impossible.	Medium5	Brute forceHash map	No attempts yet	5s	512 MB	Judgeable
Equal SumsGiven up to 20 distinct numbers, print the two lexicographically smallest distinct subsets that share the smallest repeated sum, or Impossible.	Medium5	Brute forceHash map+1	No attempts yet	20s	512 MB	Judgeable
Password Problem (Large)Choose how many typed characters to keep or erase to minimize the expected keystrokes to finish a password with known per-character correctness odds.	Medium5	ProbabilityPrefix sum+1	No attempts yet	5s	512 MB	Judgeable
Kingdom RushEarn one-star and two-star clears with star thresholds in an order that finishes every level with two stars in the fewest plays.	Medium5	GreedySorting	No attempts yet	5s	512 MB	Judgeable
Kingdom Rush (Large)Find the fewest level completions that earn a 2-star rating on every level when each level needs minimum star counts for its 1-star and 2-star plays.	Medium5	GreedySorting	No attempts yet	5s	512 MB	Judgeable
Recycled Numbers (Large)Count pairs n < m in [A, B] with equal digits where m is a rotation of n with no leading zero, counting each pair once.	Medium5	StringBrute force+1	No attempts yet	5s	512 MB	Judgeable
Gem Match CascadeTry every adjacent swap on the gem board, simulate the match and fall cascade, and report the largest number of cleared gems.	Medium5	SimulationBrute force+1	No attempts yet	5s	512 MB	Judgeable
Technology PlanningFind every goal technology plus its prerequisites and print the smallest valid research order, breaking ties lexicographically.	Medium5	Topological sortGraph	No attempts yet	5s	512 MB	Judgeable
Technology PlanningPlan the smallest set of technologies covering every goal plus its dependencies, then print the lexicographically smallest valid research order.	Medium5	Topological sortGraph+2	No attempts yet	5s	512 MB	Judgeable
Survivor (Small)Pick which foods to eat and in what order, respecting each shelf life, to maximize total survival time.	Medium5	BacktrackingDynamic programming	No attempts yet	5s	512 MB	Judgeable
Han River (Small)Count the composite houses below N that have as many divisors as house N and whose smallest prime divisor is at least M.	Medium5	Number theoryBrute force	No attempts yet	5s	512 MB	Judgeable
New Calendar (Large)From the counts of months, days per month, and days per week, compute the number of rows the year calendar occupies under the layout rules.	Medium5	MathSimulation	No attempts yet	5s	512 MB	Judgeable
Choosing a meeting place (Large)Each friend moves at their own speed, so run Dijkstra once per friend and pick the city with the smallest worst arrival time.	Medium5	Shortest pathGraph	No attempts yet	5s	512 MB	Judgeable
Infinite Garden (Small)Simulate the wall-drawing robot in the first quadrant and answer shortest path queries between even-coordinate points without crossing walls.	Medium5	BFSSimulation	No attempts yet	5s	512 MB	Judgeable
Card Shuffle (Large)Find the card at position W after moving the given blocks of a numbered M-card deck to the top C times.	Medium5	SimulationIntervals	No attempts yet	5s	512 MB	Judgeable
Best coffee (Small)Pick one coffee cup per day from kinds with limited cups and expiry days to maximize total satisfaction over K days.	Medium5	GreedySorting	No attempts yet	5s	512 MB	Judgeable
Morning Coffee (Large)Choose one cup per day from day 1 to K so no kind is drunk past its deadline and total satisfaction is largest.	Medium5	GreedyHeap+1	No attempts yet	5s	512 MB	Judgeable
Bit Count (Small)Given N, split it into nonnegative a and b with a plus b equal to N to maximize the total count of 1 bits in a and b.	Medium5	Bit manipulationDynamic programming	No attempts yet	5s	512 MB	Judgeable
Bit Count (Large)For each N, choose nonnegative a and b with a plus b equal to N to maximize the total number of 1 bits in a and b.	Medium5	Bit manipulationGreedy	No attempts yet	5s	512 MB	Judgeable
Theme Park (Large)Groups board a coaster holding at most k people in queue order and rejoin the back after riding, and R runs of earnings must be totaled.	Medium5	SimulationQueue+1	No attempts yet	5s	512 MB	Judgeable
Irregular Cakes (Small)Split the region between two polylines into G equal areas with vertical cuts and print each cut position.	Medium5	Binary searchGeometry	No attempts yet	5s	512 MB	Judgeable
Irregular Cakes (Large Input)Find the vertical cut positions that split the region between two polylines into G slices of equal area.	Medium5	GeometryBinary search+1	No attempts yet	5s	512 MB	Judgeable
Dire Straights (Small)Split the hand into groups of consecutive values to make the shortest group as long as possible.	Medium5	BacktrackingSorting	No attempts yet	5s	512 MB	Judgeable
Airport Walkways (Small)Spend up to t seconds running, choosing walkway and plain sections, to minimize travel time over a corridor of length X.	Medium5	GreedySorting	No attempts yet	5s	512 MB	Judgeable
Space Emergency (Small)Place up to two speed boosters that all finish at time t so the flagship moving from star 0 through every star in order reaches star N earliest.	Medium5	Brute forceSimulation	No attempts yet	5s	512 MB	Judgeable
FreeCell StatisticsDecide whether some day total D up to N and overall total G can yield exact win rates PD and PG.	Medium5	Number theoryBrute force	No attempts yet	5s	512 MB	Judgeable
FreeCell Statistics (Large)For each test case, decide whether exact win percentages P_D and P_G can come from some day count D up to N and some total count G.	Medium5	Number theoryMath	No attempts yet	5s	512 MB	Judgeable
The Killer Word (Small)Pick the dictionary word that makes Sean miss the most guesses under his order-based guessing rule, breaking ties by dictionary order.	Medium5	SimulationString+1	No attempts yet	5s	512 MB	Judgeable
Candy SplittingDivide the candies into two nonempty piles that look equal under addition without carries and keep the largest possible true sum for yourself.	Medium5	Bit manipulationGreedy	No attempts yet	5s	512 MB	Judgeable
Candy Splitting (Large)Split the candies into two nonempty piles with equal xor totals and keep the pile with the largest ordinary sum.	Medium5	Bit manipulationGreedy	No attempts yet	5s	512 MB	Judgeable
Music Collection SearchFor each song name, find the shortest case-insensitive substring that appears in that name alone, breaking ties by a custom lexicographic order.	Medium5	String matchingBrute force+1	No attempts yet	5s	512 MB	Judgeable
Irregular Expressions (Large)Decide if any substring of each string splits into equal start and end words of two or more syllables around a middle word.	Medium5	Brute forceString+1	No attempts yet	5s	512 MB	Judgeable
Vanishing Numbers (Small)Sort each decimal by the round it is removed from the Cantor middle-third process, placing numbers that never vanish last.	Medium5	MathSorting	No attempts yet	5s	512 MB	Judgeable
Closing the Loop (Large)Pick equal numbers of red and blue rope segments to maximize total length minus one centimeter per knot.	Medium5	GreedySorting	No attempts yet	5s	512 MB	Judgeable
Building a House (Small)Find the area of the largest axis-aligned rectangle containing only grass and shrub cells on each grid map.	Medium5	StackMatrix	No attempts yet	5s	512 MB	Judgeable
Making Chess Boards (Small)You repeatedly cut the largest alternating-color square from a hex-encoded grid and report the count for each board size.	Medium5	SimulationBrute force	No attempts yet	5s	512 MB	Judgeable
Picking Up Chicks (Small)Count the fewest adjacent swaps that let at least K chicks reach the barn by time T given positions and speeds.	Medium5	GreedyMath	No attempts yet	5s	512 MB	Judgeable
Picking Up ChicksCount the fewest adjacent swaps so at least K chicks, slowed by slower chicks ahead, reach the barn by time T.	Medium5	GreedyArray	No attempts yet	5s	512 MB	Judgeable
Snapper Chain (Large)After K snaps on a chain of N toggling snappers, decide whether power reaches the light plugged into the last one.	Medium5	Bit manipulationMath	No attempts yet	5s	512 MB	Judgeable
Fair Warning (Small)You compute the shortest wait until every elapsed time is a multiple of the largest shared divisor.	Medium5	Number theoryMath	No attempts yet	5s	512 MB	Judgeable
Theme Park Roller CoasterSimulate R rides where groups at the front board until the next group cannot fit, then return to the back; report total earnings.	Medium5	QueueSimulation+1	No attempts yet	5s	512 MB	Judgeable
Get to Work (Small)Assign drivers so every employee reaches town T using the fewest cars, and report how many cars leave each town.	Medium5	GreedySimulation+1	No attempts yet	5s	512 MB	Judgeable
Get to Work (Large)For each town, count how many drivers and passengers must leave; report per-town car counts or IMPOSSIBLE if seats do not cover riders.	Medium5	GreedyImplementation	No attempts yet	5s	512 MB	Judgeable
Doubly-sorted grid (small)Given a partially filled R by C letter grid with R and C at most 4, count the completions whose rows and columns are non-decreasing modulo 10007.	Medium5	BacktrackingDynamic programming	No attempts yet	5s	512 MB	Judgeable
Lights (Small Input)For one pillar at most, compute the areas lit by red only, green only, both, and neither within a 100 by 100 square.	Medium5	GeometryImplementation	No attempts yet	5s	512 MB	Judgeable
Crazy Rows (Small)Given an N by N binary matrix, reorder the rows using adjacent swaps so each row's rightmost 1 is at or left of its position, minimizing swaps.	Medium5	GreedySorting+2	No attempts yet	5s	512 MB	Judgeable
Crazy Rows (Large)Given a binary N x N matrix, swap adjacent rows to move every 1 to or below the main diagonal, and output the minimum number of swaps.	Medium5	GreedySorting+1	No attempts yet	5s	512 MB	Judgeable
Decision Tree (Large)Parse a nested decision tree with optional feature names, then multiply node weights along the path chosen by each animal's features.	Medium5	StringRecursion+2	No attempts yet	5s	512 MB	Judgeable
Square Math (Small)On a small grid of digits and plus/minus signs, find the shortest, then lexicographically smallest, walking expression that evaluates left to right to each query value.	Medium5	BFSBrute force+1	No attempts yet	5s	512 MB	Judgeable
Crossing the Road (Small)On a tiny grid whose intersections have periodic pedestrian lights, find the minimum time to walk from the southwest corner of the grid to the northeast corner.	Medium5	Shortest pathGraph+1	No attempts yet	5s	512 MB	Judgeable
Watersheds (Large)Each cell drains to its lowest neighbor, sinks define basins, and each basin gets the letter that makes the row-major label string smallest.	Medium5	GraphDFS+2	No attempts yet	5s	512 MB	Judgeable
Counting welcome to code jam subsequencesCount subsequences of each input text that spell the 19-character target string, printed as the last four digits.	Medium5	Dynamic programmingString	No attempts yet	5s	512 MB	Judgeable
Juice (Small Input)Given up to 10 guests with minimum fractions of three juices summing to 1, find the largest subset satisfiable by one mix.	Medium5	Brute forceGeometry+1	No attempts yet	5s	512 MB	Judgeable
Scaled Triangle (Small)Given a triangle and its rotated, translated, and shrunk copy with matching corners, find the unique fixed point of the similarity transformation.	Medium5	GeometryMath+1	No attempts yet	5s	512 MB	Judgeable
What are Birds? (Small)Given labeled bird and non-bird points in 2D, decide for unlabeled animals whether they must be birds, cannot be birds, or are unknown.	Medium5	IntervalsImplementation+1	No attempts yet	5s	512 MB	Judgeable