Problems

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Total results29,234 problems

Jumping Beans
Medium7
Simulation, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Building Moon City
Medium7
Brute force, Geometry+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hop — Don't Walk!
Medium7
BFS, Backtracking+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Air Strike
Medium7
Geometry, Binary search+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Kind of a Blur
Medium7
Math, Matrix+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Value of a Triangle
Medium7
Dynamic programming, Prefix sum+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Walsh Matrix
Medium7
Divide and conquer, Recursion+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Incidental Points
Medium7
Geometry, Hash map+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Let's Go to the Movies
Medium7
Dynamic programming, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Jonny Hates Math
Medium7
DFS, Backtracking+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
I Hate Number Theory
Medium7
Number theory, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Minimum Spanning Tree
Medium7
Minimum spanning tree, Union-find+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
What's Your Logo?
Medium7
Geometry, BFS+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Sorcerer's Donut
Medium7
String, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Long Distance Taxi
Medium7
Graph, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Encircling Circles
Medium7
Geometry, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Round Trip
Medium7
Graph, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Identically Colored Panels Connection
Medium7
DFS, BFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
And Then, How Many Are There?
Medium7
Dynamic programming, Bit manipulation+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Watchdog Corporation
Medium7
Geometry, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pollock's conjecture
Medium7
Dynamic programming, Number theory+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Word Addition
Medium7
Backtracking, Brute force+2
No attempts yet
Time limit
40s
Memory limit
128 MB
Judgeable
Discrete Speed
Medium7
Graph, Shortest path+2
No attempts yet
Time limit
8s
Memory limit
128 MB
Judgeable
Cards
Medium7
Graph, Number theory+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Secrets in Shadows
Medium7
Geometry, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Traveling by Stagecoach
Medium7
Graph, Shortest path+2
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Robot Vacuum
Medium7
BFS, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Circle and Points
Medium7
Geometry, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cookie Selection
Medium7
Heap, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Power Blogger
Medium7
Graph, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Baggage
Medium7
Math, Number theory+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Knigs of the Forest
Medium7
Heap, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Doodle
Medium7
Math, Number theory+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Allergy Test
Medium7
Combinatorics, Bit manipulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rain Fall
Medium7
Math, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Gokigen Naname
Medium7
Backtracking, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Code Theft
Medium7
String, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fixing the Bugs
Medium7
Dynamic programming, Probability
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hard Evidence
Medium7
Geometry, Binary search+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Full Tank?
Medium7
Graph, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Nested Dolls
Medium7
Sorting, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Moogle Maps
Medium7
Dynamic programming, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Amphiphilic Carbon Molecules
Medium7
Geometry, Two pointers+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Whac-a-Mole
Medium7
Dynamic programming, Geometry+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Random Walking
Medium7
Graph, Probability+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Team Dessert
Medium7
Dynamic programming, Game theory+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Gooseberry Tart BASIC
Medium7
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Standing Pins
Medium7
Graph, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The God Delusion
Medium7
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Extreme Tic-Tac-Toe
Medium7
Implementation, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Congested Networks
Medium7
Graph, Union-find+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Functional Programming Counts
Medium7
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Water?
Medium7
Prefix sum, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Martian Pits
Medium7
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hiking Trails
Medium7
Graph, Union-find+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Emergency Rations
Medium7
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Numerology
Medium7
Brute force, Implementation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Bartering
Medium7
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Ice Cream
Medium7
Greedy, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mendelian Genetics
Medium7
Sorting, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Segment Pricing
Medium7
Dynamic programming, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Network Expansion
Medium7
Graph, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Emergency Room
Medium7
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Social Network Vaccinations
Medium7
Graph, Brute force+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Cherry Picking
Medium7
Dynamic programming, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Health Plan Comparison
Medium7
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Hare and the Hedgehogs
Medium7
Geometry, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hermit Crabs
Medium7
Simulation, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Time Limit Exceeded
Medium7
Stack, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Campaign Stops
Medium7
Dynamic programming, Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sun Bathing
Medium7
Geometry, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Lunch
Medium7
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tutor Man
Medium7
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Buddy, Can You Spare a Tronk?
Medium7
Backtracking, Number theory+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Find Fame in the Disc Arena
Medium7
Graph, Dynamic programming+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Aim It Right!
Medium7
Geometry, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Locate Mining Center
Medium7
Geometry, Binary search+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
BOI-handsome Numbers
Medium7
Dynamic programming, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Spiral
Medium7
Brute force, Implementation+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Trapezoids
Medium7
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sorting
Medium7
Sorting, Array+2
No attempts yet
Time limit
0.3s
Memory limit
64 MB
Judgeable
Points
Medium7
Geometry, Hash map+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Protect Our Treasure!
Medium7
Combinatorics, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Popping Balloons
Medium7
Geometry, Intervals+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Gold Coin Game
Medium7
Game theory, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Walking the Plank
Medium7
Simulation, Queue+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Parking Ships
Medium7
Sorting, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Top 2000
Medium7
Dynamic programming, Prefix sum+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Snooker
Medium7
Simulation, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Wrong Answer
Medium7
Graph, Union-find+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Gearbox
Medium7
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Song Contest
Medium7
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Skatepark's New Ramps
Medium7
Binary search, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Road
Medium7
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Ski Lifts
Medium7
Graph, Union-find+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Attack of the Giant n-pus
Medium7
Binary search, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Polly Wants a Cracker
Medium7
Dynamic programming, String+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Shuriken Game
Medium7
Dynamic programming, Game theory+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Evolution
Medium7
Probability, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Serial Number
Medium7
Dynamic programming, Number theory
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Jumping BeansTrack how beans in a row are rearranged after T seconds of a wrap-around swapping process, printing the final order for each test case.	Medium7	SimulationMath+2	No attempts yet	1s	128 MB	Judgeable
Building Moon CityFind a Hamiltonian cycle over fewer than 9 planets minimizing road costs plus a penalty for each pair of edges that cross.	Medium7	Brute forceGeometry+2	No attempts yet	1s	128 MB	Judgeable
Hop — Don't Walk!Sliding-tile puzzle with walk and hop moves where hops flip the passed tile; find the fewest moves (depth under 10) to make all black tiles contiguous.	Medium7	BFSBacktracking+2	No attempts yet	1s	128 MB	Judgeable
Air StrikeGiven two fixed towers, a total energy T, and N missile landing points, split the energy into two disk radii to deflect as many missiles as possible and report the minimum number that hit.	Medium7	GeometryBinary search+2	No attempts yet	1s	128 MB	Judgeable
Kind of a BlurGiven a blurred grayscale image, recover the original pixel values under a Manhattan-distance averaging blur by solving the resulting linear system.	Medium7	MathMatrix+2	No attempts yet	1s	128 MB	Judgeable
Value of a TriangleGiven up to 400 rows of a triangular grid of unit triangles, find the sub-triangle with the largest sum of unit values.	Medium7	Dynamic programmingPrefix sum+2	No attempts yet	1s	256 MB	Judgeable
Walsh MatrixSum entries in one row of a Walsh matrix over columns S through E, where the matrix size 2^N can reach 2^60.	Medium7	Divide and conquerRecursion+2	No attempts yet	1s	128 MB	Judgeable
Incidental PointsFor each test case, choose two points whose segment contains the most other given points and report that count.	Medium7	GeometryHash map+2	No attempts yet	5s	128 MB	Judgeable
Let's Go to the MoviesEach family is a parent with children, and tickets are either singles or family tickets (one parent plus any subset of their own children). Find the arrangement minimizing cost, breaking ties by fewest tickets.	Medium7	Dynamic programmingGreedy+1	No attempts yet	1s	128 MB	Judgeable
Jonny Hates MathSplit a digit string into positive addends of at most 5 digits with no leading zeros that sum to a given total, minimizing the number of plus signs and breaking ties lexicographically.	Medium7	DFSBacktracking+2	No attempts yet	5s	128 MB	Judgeable
I Hate Number TheoryFor each query interval [L, U] below one million, find the maximum of a score built from prime-factor counts over all subintervals [a, b].	Medium7	Number theoryPrefix sum+1	No attempts yet	1s	128 MB	Judgeable
Minimum Spanning TreeGiven a weighted graph and several spanning trees written as nested lists, decide for each whether it is a minimum spanning tree.	Medium7	Minimum spanning treeUnion-find+2	No attempts yet	1s	128 MB	Judgeable
What's Your Logo?Count the empty closed regions formed by a rectilinear path traced by U, D, L, R moves that may cross but never overlap.	Medium7	GeometryBFS+1	No attempts yet	1s	128 MB	Judgeable
The Sorcerer's DonutOn a torus grid of letters, find the longest string that can be read twice along two non-self-overlapping straight runs in the 8 directions, breaking ties lexicographically.	Medium7	StringBrute force+2	No attempts yet	1s	128 MB	Judgeable
Long Distance TaxiGiven an undirected weighted graph, a tank range, and a set of refueling cities, find the shortest route from src to dest that never runs out of gas.	Medium7	GraphShortest path+2	No attempts yet	1s	128 MB	Judgeable
Encircling CirclesGiven n circles and a radius r, find the length of the boundary of the union of all radius-r circles that enclose every given circle.	Medium7	GeometryMath+2	No attempts yet	1s	128 MB	Judgeable
Round TripFind a non-descending path from town 1 to town n and a non-ascending path back, sharing the first-visit visa fee of each town, minimizing total road cost plus fees.	Medium7	GraphShortest path+2	No attempts yet	1s	128 MB	Judgeable
Identically Colored Panels ConnectionOn a grid of up to 8 by 8 panels in six colors, the upper-left connected region changes color five times, absorbing same-colored neighbors; maximize the final region of the target color.	Medium7	DFSBFS+2	No attempts yet	1s	128 MB	Judgeable
And Then, How Many Are There?Given stacked discs of four colors, repeatedly remove two same-colored discs that are both uncovered; find the maximum number of discs removable.	Medium7	Dynamic programmingBit manipulation+2	No attempts yet	5s	128 MB	Judgeable
Watchdog CorporationGiven a leash length and an axis-aligned rectangular building, find the perimeter of the region a dog tethered at the origin can roam without entering the building.	Medium7	GeometryMath+2	No attempts yet	1s	128 MB	Judgeable
Pollock's conjectureFor each integer below 10^6, find the fewest tetrahedral numbers that sum to it, and the fewest odd tetrahedral numbers that do.	Medium7	Dynamic programmingNumber theory+2	No attempts yet	1s	128 MB	Judgeable
Word AdditionCount letter-to-digit assignments that make a cryptarithmetic addition of up to 12 words valid, with no leading zeros and distinct digits per letter.	Medium7	BacktrackingBrute force+2	No attempts yet	40s	128 MB	Judgeable
Discrete SpeedFind the fastest route from a start to a goal city where a car enters each road at an integer speed, changes speed by at most 1 per city, starts and ends at speed 1, and cannot U-turn.	Medium7	GraphShortest path+2	No attempts yet	8s	128 MB	Judgeable
CardsGiven blue and red cards with numbers, find the maximum number of blue-red pairs whose two numbers share a common divisor greater than 1.	Medium7	GraphNumber theory+2	No attempts yet	5s	128 MB	Judgeable
Secrets in ShadowsGiven unit-disk column centers, find the minimum and maximum total width of their infinite shadow strips as the sun direction varies from east to west.	Medium7	GeometrySorting+1	No attempts yet	1s	128 MB	Judgeable
Traveling by StagecoachWith up to 8 one-use tickets, each giving a speed, find the fastest route from city a to city b, or report Impossible.	Medium7	GraphShortest path+2	No attempts yet	3s	128 MB	Judgeable
Robot VacuumFind the minimum number of moves for a robot to visit and clean all dirty cells in a grid with furniture, or report -1 if some are unreachable.	Medium7	BFSShortest path+2	No attempts yet	1s	256 MB	Judgeable
Circle and PointsGiven up to 300 points, find the maximum number coverable by one radius-1 circle, using a sweep over candidate centers.	Medium7	GeometryBrute force+2	No attempts yet	1s	128 MB	Judgeable
Cookie SelectionProcess a stream of cookie insertions and median requests; each request outputs the upper median of the currently held multiset, supporting up to 600,000 operations.	Medium7	HeapImplementation+2	No attempts yet	1s	128 MB	Judgeable
Power BloggerFind the cheapest closed walk from city 1 that traverses every required edge at least once, using optional extra edges.	Medium7	GraphDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
BaggageGiven bag drop positions on a circular belt of length L, find the maximum straight-belt speed so that no dropping bag lands within 1 m of another, as a reduced fraction.	Medium7	MathNumber theory+2	No attempts yet	1s	128 MB	Judgeable
Knigs of the ForestGiven the strengths and entry years of all competing moose, find the year Karl-Algtav becomes champion, or report unknown.	Medium7	HeapSimulation+2	No attempts yet	1s	128 MB	Judgeable
DoodleA diagonal walk bounces off the rectangle's borders and corners; count how many distinct cells it marks before returning to the start.	Medium7	MathNumber theory+2	No attempts yet	1s	128 MB	Judgeable
Allergy TestFind the shortest non-adaptive schedule for applying allergens on a single morning each day so that every reaction pattern identifies exactly the allergy set.	Medium7	CombinatoricsBit manipulation+2	No attempts yet	1s	128 MB	Judgeable
Rain FallGiven a leak height, drain rate, rain duration, wait time, and observed level, find the minimum and maximum total rainfall consistent with the reading.	Medium7	MathSimulation+1	No attempts yet	1s	128 MB	Judgeable
Gokigen NanameFill an n by n grid with one diagonal per cell so each numbered lattice point has exactly that many diagonal endpoints and no diagonal cycle forms.	Medium7	BacktrackingDFS+2	No attempts yet	1s	128 MB	Judgeable
Code TheftNormalize two sets of source lines and find the longest consecutive run of lines common to both, reporting the length and which files achieve it.	Medium7	StringHash map+1	No attempts yet	1s	128 MB	Judgeable
Fixing the BugsWith B bugs, T hours, and a failure factor f, choose each hour's bug by dynamic programming to maximize the expected total severity fixed.	Medium7	Dynamic programmingProbability	No attempts yet	1s	128 MB	Judgeable
Hard EvidenceGiven a convex polygon strictly inside a circle centered at the origin, find the point on the circle maximizing the angular width of the polygon and print that angle to 10 decimals.	Medium7	GeometryBinary search+2	No attempts yet	1s	128 MB	Judgeable
Full Tank?For each query (tank capacity c, start s, goal e), find the minimum fuel cost to drive from s to e, buying gas only at cities at given prices; output impossible if unreachable.	Medium7	GraphShortest path+2	No attempts yet	1s	128 MB	Judgeable
Nested DollsGiven a set of dolls with widths and heights, partition them into the fewest strictly increasing chains in both dimensions, which equals the longest antichain by Dilworth's theorem.	Medium7	SortingDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
Moogle MapsChoose c of h house locations to store so that the average linear interpolation error over all houses is minimized, with endpoints always stored.	Medium7	Dynamic programmingMath+2	No attempts yet	1s	128 MB	Judgeable
Amphiphilic Carbon MoleculesPlace a single line to maximize the number of particles that dissolve: hydrophilic on the water side plus hydrophobic on the acetone side, counting any particle on the line.	Medium7	GeometryTwo pointers+2	No attempts yet	5s	128 MB	Judgeable
Whac-a-MoleGiven each mole's position and time, find the maximum number of moles whacked while the hammer moves at most distance d between time steps.	Medium7	Dynamic programmingGeometry+1	No attempts yet	1s	128 MB	Judgeable
Random WalkingFor each graph, decide whether every bit position in every one of k random walk outputs has a 1-probability strictly between 25% and 75%.	Medium7	GraphProbability+2	No attempts yet	1s	128 MB	Judgeable
Team DessertDesserts sit in a row; two alternating teams take from either end, and the first-picking team wants the smallest total weight it can guarantee against optimal play.	Medium7	Dynamic programmingGame theory+2	No attempts yet	1s	128 MB	Judgeable
Gooseberry Tart BASICImplement a fast interpreter for a small BASIC subset with LET, GOTO, IF, FOR/NEXT, OUT, and COMMENT, printing each program's output.	Medium7	ImplementationSimulation+2	No attempts yet	1s	128 MB	Judgeable
Standing PinsGiven fallen wires specified by endpoints, reconstruct the unique grid of pin heights, or report no solution when zero or multiple height assignments exist.	Medium7	GraphBrute force+2	No attempts yet	1s	128 MB	Judgeable
The God DelusionOn a tiny grid each atom holds one numbered electron except a blank; slide electrons into empty neighbours to send each to its own atom in the fewest moves.	Medium7	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
Extreme Tic-Tac-ToeRead N-dimensional 3^N-cell tic-tac-toe boards (N up to 10) and count straight lines of three identical X or O symbols, ignoring lines with empty cells.	Medium7	ImplementationBrute force+2	No attempts yet	1s	128 MB	Judgeable
Congested NetworksFor each connected graph with at most 40 nodes, find the maximum number of edge-disjoint paths between any pair of nodes.	Medium7	GraphUnion-find+2	No attempts yet	1s	128 MB	Judgeable
Functional Programming CountsImplement an interpreter for a tiny functional language with variables, single-parameter functions, and call-count profiling per definition line.	Medium7	ImplementationSimulation+2	No attempts yet	1s	128 MB	Judgeable
Water?Given an h by w grid of letters and a set of special letters, find the subrectangle with both sides at least m whose fraction of special pixels is maximum, breaking ties by larger area.	Medium7	Prefix sumBrute force+2	No attempts yet	1s	128 MB	Judgeable
Martian PitsOn a grid with pits, command a rover that moves at speed 0 to 5 to reach the destination stopped in the fewest seconds.	Medium7	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
Hiking TrailsGiven a graph, add the fewest edges so it becomes connected and every vertex has even degree.	Medium7	GraphUnion-find+2	No attempts yet	1s	128 MB	Judgeable
Emergency RationsChoose boxes with a capacity and an expiry day to eat one unit daily starting day 1; report the last reachable day and the fewest boxes needed.	Medium7	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
NumerologyFor each (n, p), find the smallest base 2 to 10^6 where the digits of n form a pattern repetition and print the digit sequence.	Medium7	Brute forceImplementation+1	No attempts yet	2s	128 MB	Judgeable
BarteringGiven starting items, wanted items, and up to 20 barter trades usable at most M times, find the fewest trades to hold all wanted items while never exceeding 5 held items.	Medium7	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
Ice CreamFind the minimum cost to buy single, double, and triple scoops from two flavors so every customer's vanilla and chocolate counts are met without contaminating one-flavor orders.	Medium7	GreedyDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
Mendelian GeneticsFor each data set, find the n largest values among the ceil((x+y)/2) hybrid sizes formed by all pairs of n given sizes, sorted descending.	Medium7	SortingGreedy+1	No attempts yet	1s	128 MB	Judgeable
Segment PricingChoose a non-increasing fare for each boarding stop, with riders boarding only if their budget covers it, to maximize total revenue.	Medium7	Dynamic programmingGreedy+2	No attempts yet	1s	128 MB	Judgeable
Network ExpansionGiven a connected rail network, up to 10 priced expansion routes, and a passenger demand matrix, pick an affordable subset that maximizes the drop in total travel time.	Medium7	GraphBrute force+2	No attempts yet	1s	128 MB	Judgeable
Emergency RoomSimulate patients taking the lowest free seat on arrival, track who sits within 2 metres for 20 consecutive minutes, and count infections spreading one day later.	Medium7	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
Social Network VaccinationsGiven a graph with n at most 30 and D at most 6, choose D vertices to vaccinate so that the largest connected component remaining is as small as possible.	Medium7	GraphBrute force+2	No attempts yet	2s	128 MB	Judgeable
Cherry PickingChoose one premium per category so at least m patients are insured and total premiums minus benefits is maximized.	Medium7	Dynamic programmingSorting+2	No attempts yet	1s	128 MB	Judgeable
Health Plan ComparisonParse free-text health plan descriptions to extract premiums and copay rules, then compute each plan's total yearly cost across the given visits.	Medium7	StringImplementation+2	No attempts yet	1s	128 MB	Judgeable
The Hare and the HedgehogsHedgehogs of equal speed start at given points and may move freely; find the maximum number of legs they can collectively reach exactly when the hare arrives.	Medium7	GeometryDynamic programming+1	No attempts yet	1s	128 MB	Judgeable
Hermit CrabsSimulate hermit crabs that outgrow shells over time and fight for larger unoccupied shells, then list survivors at time T.	Medium7	SimulationSorting+2	No attempts yet	1s	128 MB	Judgeable
Time Limit ExceededParse nested loops with arguments x, y, or integers, compute the Big-O polynomial of basic operations, and print terms sorted by degree.	Medium7	StackImplementation+2	No attempts yet	1s	128 MB	Judgeable
Campaign StopsPick campaign stops and a round tour from city 1 that sways the most voters within the available hours.	Medium7	Dynamic programmingGraph	No attempts yet	1s	128 MB	Judgeable
Sun BathingGiven a rectangular body, a circular parasol, and a sun angle range, report the percentage of the body lit by the sun at some moment.	Medium7	GeometryImplementation+1	No attempts yet	1s	128 MB	Judgeable
LunchPick one meeting point and one restaurant that every person can reach so the group's round-trip walking distance is minimized.	Medium7	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
Tutor ManOn a honeycomb of domino tiles where only matching numbers can be crossed, find the shortest path from tile 1 to the last tile of the last row.	Medium7	BFSGraph+1	No attempts yet	1s	256 MB	Judgeable
Buddy, Can You Spare a Tronk?Count and list all multisets of n distinct unit fractions summing to exactly 1, with a repetition limit and forbidden denominators.	Medium7	BacktrackingNumber theory+2	No attempts yet	5s	128 MB	Judgeable
Find Fame in the Disc ArenaA DAG gives games with fame values and prerequisite sets; pick a closed-under-prerequisites set (possibly empty) maximizing total fame.	Medium7	GraphDynamic programming+2	No attempts yet	5s	128 MB	Judgeable
Aim It Right!A cue ball starts at A inside a square table with a circular hole at the center; find the fewest wall rebounds (under 10) to reach B without entering the hole.	Medium7	GeometryMath+2	No attempts yet	1s	128 MB	Judgeable
Locate Mining CenterPlace a center on integer coordinates minimizing the largest Manhattan distance to given sites, breaking ties by Euclidean distance to the origin and then lexicographically.	Medium7	GeometryBinary search+2	No attempts yet	1s	128 MB	Judgeable
BOI-handsome NumbersCount digit strings over {1,2,3} of length n that avoid forbidden adjacent pairs, comparing them under an order given by a permutation of positions, up to a bound B.	Medium7	Dynamic programmingCombinatorics+2	No attempts yet	1s	256 MB	Judgeable
SpiralOn an N by N grid with blocked fountain cells, find the longest path made of four straight segments turning only right, never revisiting a field.	Medium7	Brute forceImplementation+2	No attempts yet	5s	128 MB	Judgeable
TrapezoidsPick the most pairwise disjoint trapezoids between two lines and count those optimal sets modulo 30013.	Medium7	Dynamic programmingSorting+1	No attempts yet	1s	128 MB	Judgeable
SortingGiven a permutation, find all gap sizes X for which repeatedly scanning and swapping positions i and i+X until a pass makes no swap leaves the array sorted.	Medium7	SortingArray+2	No attempts yet	0.3s	64 MB	Judgeable
PointsCount the distinct straight lines in 3D space that pass through at least three of the given points.	Medium7	GeometryHash map+2	No attempts yet	1s	128 MB	Judgeable
Protect Our Treasure!Given each pirate's set of keys, list every minimal group whose union covers all locks, ordered by size then lexicographically.	Medium7	CombinatoricsBrute force+2	No attempts yet	1s	128 MB	Judgeable
Popping BalloonsEach balloon is a circle not containing the origin. Find the minimum number of halflines from the origin that all cross at least one circle.	Medium7	GeometryIntervals+2	No attempts yet	1s	128 MB	Judgeable
Gold Coin GameGiven S coins and a legal move set of powers of K, find the smallest first move that guarantees a win for the starting player, or 0 if none exists.	Medium7	Game theoryMath+1	No attempts yet	1s	128 MB	Judgeable
Walking the PlankSimulate pirates crossing a one-at-a-time plank to ferry N items, honoring side-priority, FIFO queues, and ties broken by slowest pirate.	Medium7	SimulationQueue+1	No attempts yet	1s	128 MB	Judgeable
Parking ShipsThe captain's parking interval is fixed; place the other ships on a line so that as many ship intervals as possible cover their house centers.	Medium7	SortingGreedy+1	No attempts yet	1s	128 MB	Judgeable
Top 2000Partition a fixed sequence of singles into contiguous blocks, letting each block run under or over M minutes with per-minute penalties, and minimize the total penalty.	Medium7	Dynamic programmingPrefix sum+2	No attempts yet	1s	128 MB	Judgeable
SnookerGiven the sequence of potted ball values in a valid snooker game with hidden scores, find the earliest shot after which the trailing player can no longer win.	Medium7	SimulationGreedy+2	No attempts yet	1s	128 MB	Judgeable
Wrong AnswerGiven horizontal and vertical words, remove the fewest words so no horizontal and vertical word demand different letters at a shared cell.	Medium7	GraphUnion-find+2	No attempts yet	1s	256 MB	Judgeable
GearboxGiven gears of unknown teeth counts grouped on rods and pairs of interlocked gears, decide whether every rod can turn for any assignment of teeth counts to gear types.	Medium7	GraphDFS+2	No attempts yet	1s	128 MB	Judgeable
Song ContestGiven each nation's voting type, capital, and quality rank, split one act into s-1 parts to maximize the points it receives from all nations.	Medium7	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
The Skatepark's New RampsRamps have allowed height intervals and a fixed concrete budget; volume scales with the triangle area, so find the minimum and maximum possible height spread.	Medium7	Binary searchGreedy+2	No attempts yet	1s	128 MB	Judgeable
RoadGiven a road with passing places and a matrix describing where each eastbound car passes each westbound car, compute the minimum total time to realize that schedule. Cars drive at 12.5 m/s or wait, and cars in the same direction keep 25 m apart.	Medium7	ImplementationSimulation+2	No attempts yet	1s	128 MB	Judgeable
Ski LiftsGiven a grid of heights, find the minimum number of unidirectional lifts so any cell can reach any other by skiing downhill or level and using lifts.	Medium7	GraphUnion-find+2	No attempts yet	1s	128 MB	Judgeable
Attack of the Giant n-pusAssign p pirates to n tentacles so the captain can reach the head as early as possible; each pirate pins one tentacle, the captain starts when all are pinned.	Medium7	Binary searchGreedy+2	No attempts yet	1s	128 MB	Judgeable
Polly Wants a CrackerMatch each spoken word to a distinct original word minimizing total Levenshtein edit distance, and report that minimum sum.	Medium7	Dynamic programmingString+2	No attempts yet	1s	128 MB	Judgeable
Shuriken GameTwo players remove 1 to N shurikens from a pile, but a player cannot repeat the opponent's previous move; find the smallest winning first move.	Medium7	Dynamic programmingGame theory+1	No attempts yet	1s	128 MB	Judgeable
EvolutionGiven N DNA strings linked in an unknown parent-child order, compute each creature's probability of being the original ancestor.	Medium7	ProbabilityBit manipulation+1	No attempts yet	1s	128 MB	Judgeable
Serial NumberGiven distinct serial numbers and a modulus M, choose the largest subset whose sum is a multiple of M.	Medium7	Dynamic programmingNumber theory	No attempts yet	3s	128 MB	Judgeable