Problems

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Total results29,423 problems

Tower Defense Game
Medium6
Graph, Greedy+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Maze
Medium6
Geometry, Math
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Snowstorm
Medium6
Intervals, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fireflies
Medium6
Binary search, Geometry
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sabotage
Medium6
Binary search, Prefix sum
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Counting Friends
Medium6
Graph, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mooo Moo
Medium6
Dynamic programming, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cow Optics
Medium6
Simulation, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fair Photography
Medium6
Prefix sum, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Odometer
Medium6
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dueling GPSs
Medium6
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Taxis
Medium6
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
IOI Manju
Medium6
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Crane Balancing
Medium6
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Surveillance Cameras
Medium6
Greedy, Intervals+1
No attempts yet
Time limit
4s
Memory limit
512 MB
Judgeable
KRAVE
Medium6
Intervals, Binary search+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Orchard
Medium6
Matrix, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Obelisk
Medium6
Shortest path, BFS+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Big Circle
Medium6
Geometry, Sorting
No attempts yet
Time limit
1s
Memory limit
16 MB
Judgeable
Mascot Song
Medium6
Array, Simulation
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Decreasing Sequences of Points
Medium6
Dynamic programming, Prefix sum
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Computer Network
Medium6
Graph, Shortest path
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Tinted Glass Window
Medium6
Prefix sum, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Lazy Fox
Medium6
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
King Gruff
Medium6
Shortest path, Sorting+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
The Shell Game
Medium6
Minimum spanning tree, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Hero
Medium6
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Printing Plate
Medium6
Binary search, Sliding window+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Spectator Seats
Medium6
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Jam Factory
Medium6
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Colored Bead Plate
Medium6
Probability, Simulation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
KCM Travel
Medium6
Dynamic programming, Shortest path+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Expected Ultimate Damage
Medium6
Probability, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cluedo
Medium6
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Quality of Living
Medium6
Binary search, Prefix sum+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Vampire
Medium6
Geometry, Intervals+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Encryption System
Medium6
Brute force, Simulation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Don't Cross the Circles!
Medium6
Graph, Geometry+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Two Knights' Poem
Medium6
BFS, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Driving license test
Medium6
Dynamic programming, Graph
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Mutation
Medium6
String matching, Hash map
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Amanda Lounges
Medium6
Graph, BFS
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
How many squares?
Medium6
Geometry, Hash map
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Ancient Cave Expedition
Medium6
Dynamic programming, Topological sort+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
JuQueen
Medium6
Segment tree
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Not a subsequence
Medium6
Greedy, String+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Pizza veto voting
Medium6
Greedy, Game theory+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Lift Problems
Medium6
Dynamic programming, Prefix sum
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Talent Selection
Medium6
Greedy, Binary search+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Ranks in groups
Medium6
Union-find, Sorting+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Karel the Robot
Medium6
Simulation, Graph
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Fortress Construction
Medium6
Geometry, Brute force
No attempts yet
Time limit
7s
Memory limit
256 MB
Judgeable
Dropping Directions
Medium6
Graph, DFS
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Excellent Engineers
Medium6
Sorting, Segment tree
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Automotive Navigation
Medium6
BFS, Graph+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Group of Strangers
Medium6
Graph, Combinatorics
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Irrigation Lines
Medium6
Graph, DFS+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Speed Skills
Medium6
Simulation, Math
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Help Cupid
Medium6
Dynamic programming, Sorting
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Facility Locations
Medium6
Union-find, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Landline Telephone Network
Medium6
Minimum spanning tree, Union-find+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Aquarium Tank
Medium6
Geometry, Binary search
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Anagram Pyramids
Medium6
Graph, BFS+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Matryoshka Dolls
Medium6
Dynamic programming, Sorting
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Repel
Medium6
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Number Picking Game
Medium6
Dynamic programming, Intervals
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Mosquito, You Are Mine
Medium6
Geometry, Brute force
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Plotting Polynomials
Medium6
Math, Combinatorics
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Island Buses
Medium6
Union-find, Graph+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Multi-touch gesture classification
Medium6
Simulation, Geometry+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Unicycle counting
Medium6
Dynamic programming, Bit manipulation+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Choosing Numbers
Medium6
Number theory, Brute force
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Loopy transit
Medium6
Graph, Backtracking+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Bricks
Medium6
Greedy, Prefix sum+1
No attempts yet
Time limit
6s
Memory limit
256 MB
Judgeable
Digi Comp II
Medium6
Topological sort, Dynamic programming
No attempts yet
Time limit
7s
Memory limit
256 MB
Judgeable
Finding a Line
Medium6
Probability, Geometry+1
No attempts yet
Time limit
4s
Memory limit
256 MB
Judgeable
Knapsack Collection
Medium6
Sorting, Prefix sum+1
No attempts yet
Time limit
4s
Memory limit
512 MB
Judgeable
MAFIJA
Medium6
Dynamic programming, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Dorm Party
Medium6
Dynamic programming, Greedy+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Bob's House Site
Medium6
Stack, Matrix+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Hill Numbers
Medium6
Dynamic programming, Combinatorics
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Towers
Medium6
Backtracking, Brute force
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Gold Leaf
Medium6
Brute force, Simulation+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Increasing Numbers
Medium6
Combinatorics, Dynamic programming
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Epic Win!
Medium6
Shortest path, Graph+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Christmas Wheat
Medium6
Sorting, Prefix sum+2
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Parliament Party Split
Medium6
Simulation, Graph+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Bulletproof Glass Testing Budget
Medium6
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Web Service Dependencies
Medium6
Dynamic programming, Topological sort+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Concatenating Parenthesis Strings
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
RLE Replacement
Medium6
String matching, Two pointers+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Everlasting Zero
Medium6
Topological sort, Graph
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
ZGODAN
Medium6
Greedy, String+1
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Holstein Fence
Medium6
Brute force, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Meeting Time
Medium6
Dynamic programming, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Fegla's Scooter Test Ride
Medium6
BFS, Shortest path+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Hamzawy
Medium6
String matching
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Fouad
Medium6
Dynamic programming, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
JOI Park
Medium6
Shortest path, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Maximum Average Segment
Medium6
Binary search, Prefix sum
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Tower Defense GameSimulate the greedy sweep that places an improved tower at each town in increasing order unless an earlier tower already covers it within distance two.	Medium6	GraphGreedy+1	No attempts yet	3s	512 MB	Judgeable
MazeDecide whether a string of left and right turns can appear on a single walk around an axis-aligned polygon with right angles.	Medium6	GeometryMath	No attempts yet	3s	512 MB	Judgeable
SnowstormSimulate plows clearing road intervals in order of smallest remaining uncovered length and print the clearing order.	Medium6	IntervalsSimulation+2	No attempts yet	1s	128 MB	Judgeable
FirefliesChoose a shutter time that minimizes the side length of an axis-aligned square holding all fireflies moving at constant velocities.	Medium6	Binary searchGeometry	No attempts yet	1s	128 MB	Judgeable
SabotageRemove a contiguous block of middle machines, keeping the first and last, so the average output of the machines left is as small as possible.	Medium6	Binary searchPrefix sum	No attempts yet	1s	128 MB	Judgeable
Counting FriendsRemoving one of N+1 listed counts, find every entry whose removal leaves counts realizable as mutual friendships among N cows.	Medium6	GraphSorting	No attempts yet	1s	128 MB	Judgeable
Mooo MooFind the fewest cows whose breed volumes explain the recorded volumes when each field spills its total minus one into the next field.	Medium6	Dynamic programmingGreedy	No attempts yet	1s	128 MB	Judgeable
Cow OpticsCount empty integer points where one added 45-degree mirror steers the northbound laser from the origin to the barn through the existing mirrors.	Medium6	SimulationSorting+1	No attempts yet	1s	128 MB	Judgeable
Fair PhotographyCows at distinct positions are white or spotted, and after repainting some white cows you need the widest interval with equal counts.	Medium6	Prefix sumHash map+1	No attempts yet	1s	128 MB	Judgeable
OdometerCount the integers from X to Y with one digit occupying at least half of their decimal digits, ignoring leading zeros.	Medium6	Dynamic programmingCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
Dueling GPSsFind a route from intersection 1 to N that minimizes the count of roads lying off either GPS shortest path to the farm.	Medium6	Shortest pathGraph	No attempts yet	1s	128 MB	Judgeable
TaxisBoard taxis at their home towns, each charging its fare for up to its road limit, to travel from town 1 to town N at minimum cost.	Medium6	Shortest pathGraph+1	No attempts yet	1s	128 MB	Judgeable
IOI ManjuChoose boxes and fill them with the priciest manju so packed value minus box cost is as large as possible.	Medium6	Dynamic programmingSorting+1	No attempts yet	1s	256 MB	Judgeable
Crane BalancingFind the range of extra weight at the first vertex that keeps the polygon balanced on the x-axis.	Medium6	GeometryMath	No attempts yet	1s	128 MB	Judgeable
Surveillance CamerasChoose the fewest circular arcs that cover all N rooms on a circle, or report impossible.	Medium6	GreedyIntervals+1	No attempts yet	4s	512 MB	Judgeable
KRAVEYou extend a horizontal or vertical fence from each given point across its current field and report the two resulting areas in order.	Medium6	IntervalsBinary search+1	No attempts yet	5s	256 MB	Judgeable
OrchardPick one rectangle for Bert to minimize the bananas left outside it plus the apples inside it.	Medium6	MatrixPrefix sum+1	No attempts yet	2s	512 MB	Judgeable
ObeliskRoll a 1x1xM block across stacked grid floors with holes and find the fewest tilts to stand it upright on the target cell.	Medium6	Shortest pathBFS+1	No attempts yet	2s	512 MB	Judgeable
Big CircleGiven up to 100000 points on a single circle, find the smallest Euclidean distance between any two of them.	Medium6	GeometrySorting	No attempts yet	1s	16 MB	Judgeable
Mascot SongMaintain an array under point updates and left rotations, reporting the number of maximal strictly increasing runs after each query.	Medium6	ArraySimulation	No attempts yet	1s	32 MB	Judgeable
Decreasing Sequences of PointsCount sequences of lattice points on the diagonals x+y=a_i with nondecreasing x and nonincreasing y.	Medium6	Dynamic programmingPrefix sum	No attempts yet	1s	256 MB	Judgeable
Computer NetworkFind a shortest route between computers a and b in a hidden network, using message queries that report intermediate computer counts within a query limit.	Medium6	GraphShortest path	No attempts yet	1s	64 MB	Judgeable
Tinted Glass WindowN overlapping rectangles each add an integer tint to the area they cover, and you must find the total area whose summed tint is at least T.	Medium6	Prefix sumSorting+1	No attempts yet	1s	256 MB	Judgeable
Lazy FoxStarting from the origin, visit neighbors so each hop is strictly shorter than the last and collect the maximum number of treats.	Medium6	Dynamic programmingSorting+1	No attempts yet	1s	256 MB	Judgeable
King GruffFor each query, sum the shutdown costs of roads lying on some A to B path whose total length is at most D.	Medium6	Shortest pathSorting+1	No attempts yet	2s	256 MB	Judgeable
The Shell GameBuy interval parity hints to fix every ball position while minimizing the worst-case total price.	Medium6	Minimum spanning treeGraph	No attempts yet	1s	256 MB	Judgeable
HeroOrder n monsters so a hero with health z survives each d_i hit and collects each a_i reward, printing TAK with the order or NIE.	Medium6	GreedySorting	No attempts yet	1s	256 MB	Judgeable
Printing PlateFind the shortest plate that, pressed at every aligned position, leaves each fixed stripe in its own pure color.	Medium6	Binary searchSliding window+1	No attempts yet	1s	256 MB	Judgeable
Spectator SeatsPrint the number of seats on circles D1 to D2 with no other seat on the same ray from the center.	Medium6	Number theoryMath+1	No attempts yet	1s	64 MB	Judgeable
Jam FactoryConnect two source vats to a destination vat with minimum total pipe cost, where a shared pipe is paid once.	Medium6	Shortest pathGraph	No attempts yet	1s	256 MB	Judgeable
Colored Bead PlateRun up to 16 random bead drops and tilts on a 4x4 plate and report the probability that the final layout matches the target.	Medium6	ProbabilitySimulation+1	No attempts yet	2s	1024 MB	Judgeable
KCM TravelFind the fastest route from airport 1 to airport N using flights with costs and times without exceeding budget M, or report that it is impossible.	Medium6	Dynamic programmingShortest path+1	No attempts yet	3s	256 MB	Judgeable
Expected Ultimate DamageThe champion casts the ultimate N times with random doubling or plus-one effects on attack and ability, and you compute the expected sum of their product.	Medium6	ProbabilityMath	No attempts yet	1s	256 MB	Judgeable
CluedoFind the hidden triple (murderer, location, weapon) by making guesses; each wrong guess returns one arbitrary component that is incorrect.	Medium6	Brute forceImplementation+2	No attempts yet	1s	256 MB	Judgeable
Quality of LivingFind the smallest median among all H by W subrectangles of a grid holding the numbers 1 to R times C.	Medium6	Binary searchPrefix sum+1	No attempts yet	5s	256 MB	Judgeable
VampireA circular sun of radius r rises from the horizon behind rectangular buildings, and each dataset asks for the last time the whole disk stays hidden.	Medium6	GeometryIntervals+1	No attempts yet	3s	256 MB	Judgeable
Encryption SystemGiven an encrypted string, list every original string that the chained first-letter replacement turns into it.	Medium6	Brute forceSimulation+1	No attempts yet	1s	256 MB	Judgeable
Don't Cross the Circles!Decide whether two points can be joined by a curve that crosses none of up to 100 given circle circumferences.	Medium6	GraphGeometry+1	No attempts yet	1s	256 MB	Judgeable
Two Knights' PoemDecide whether two knights moving in chess-knight steps on a 40-key keyboard can type each given poem, using the other knight on Shift for capitals.	Medium6	BFSGraph	No attempts yet	1s	256 MB	Judgeable
Driving license testMove only right and down from the top left corner to the bottom right corner with at most G fuel to arrive as early as possible.	Medium6	Dynamic programmingGraph	No attempts yet	2s	256 MB	Judgeable
MutationCount overlapping occurrences in a DNA string of a marker and all strings formed by reversing one substring of the marker.	Medium6	String matchingHash map	No attempts yet	2s	256 MB	Judgeable
Amanda LoungesChoose the fewest airports for lounges so every route has zero, exactly one, or two lounges as required.	Medium6	GraphBFS	No attempts yet	2s	256 MB	Judgeable
How many squares?Count quadruples of the given infinite lines that form the four sides of a square.	Medium6	GeometryHash map	No attempts yet	1s	256 MB	Judgeable
Ancient Cave ExpeditionFrom cave 1, choose a route that only moves deeper to maximize treasure values minus tunnel costs, breaking profit ties by lexicographic order.	Medium6	Dynamic programmingTopological sort+1	No attempts yet	1s	256 MB	Judgeable
JuQueenApply point and range frequency steps to cores clamped between 0 and N and report applied steps or queried states.	Medium6	Segment tree	No attempts yet	3s	512 MB	Judgeable
Not a subsequenceGiven alphabet size k and string s, find the length of the shortest string over the alphabet that is not a subsequence of s and count such strings modulo 1e9+7.	Medium6	GreedyString+1	No attempts yet	2s	256 MB	Judgeable
Pizza veto votingDecide whether your vetoes can keep your favorite pizza standing when Alice always vetoes the highest-calorie kind and Bob the lowest.	Medium6	GreedyGame theory+1	No attempts yet	3s	256 MB	Judgeable
Lift ProblemsDecide the lift stops for given per-floor student counts to minimize total annoyance from stops and skipped floors.	Medium6	Dynamic programmingPrefix sum	No attempts yet	1s	256 MB	Judgeable
Talent SelectionHand out all fixed-value stickers to candidates so as many favorites as possible finish among the top s scorers.	Medium6	GreedyBinary search+1	No attempts yet	3s	256 MB	Judgeable
Ranks in groupsGroups of students merge together and each query asks for the score rank of one student inside its current group.	Medium6	Union-findSorting+1	No attempts yet	5s	256 MB	Judgeable
Karel the RobotGiven a maze and a short cyclic command program, count the starting squares from which the robot eventually reaches the exit.	Medium6	SimulationGraph	No attempts yet	3s	256 MB	Judgeable
Fortress ConstructionChoose up to four of the given points as corners of a convex polygon with maximum area.	Medium6	GeometryBrute force	No attempts yet	7s	256 MB	Judgeable
Dropping DirectionsPlace the fewest directing signs at 4-way intersections so a walker who otherwise goes straight reaches the goal from any start.	Medium6	GraphDFS	No attempts yet	2s	256 MB	Judgeable
Excellent EngineersCount the engineers no rival beats in all three skill ranks for each test case.	Medium6	SortingSegment tree	No attempts yet	3s	256 MB	Judgeable
Automotive NavigationFrom a street map, a start point, and per-step distance and compass readings, the program lists every location where the car can be at time t.	Medium6	BFSGraph+1	No attempts yet	5s	256 MB	Judgeable
Group of StrangersCount the triples of users where none of the three pairs are connected.	Medium6	GraphCombinatorics	No attempts yet	2s	256 MB	Judgeable
Irrigation LinesOpen the fewest row and column lines so every planted cell shares a row or column with an open line.	Medium6	GraphDFS+1	No attempts yet	1s	256 MB	Judgeable
Speed SkillsSimulate Anna's car as its speed averages with overlapping cars every quarter second and report its arrival time and speed.	Medium6	SimulationMath	No attempts yet	3s	256 MB	Judgeable
Help CupidGiven N time zones, split everyone into pairs to minimize the total circular hour difference.	Medium6	Dynamic programmingSorting	No attempts yet	3s	256 MB	Judgeable
Facility LocationsDecide whether k candidate locations can be chosen so every client is served at zero cost.	Medium6	Union-findMath	No attempts yet	1s	256 MB	Judgeable
Landline Telephone NetworkFind the cheapest network joining all buildings so no route between two buildings passes through a different insecure building.	Medium6	Minimum spanning treeUnion-find+2	No attempts yet	2s	256 MB	Judgeable
Aquarium TankA convex polygon tank of depth D holds L litres of water, and the task asks for the height of the water surface.	Medium6	GeometryBinary search	No attempts yet	1s	256 MB	Judgeable
Anagram PyramidsDecide whether dictionary words can link the base word to the apex word by deleting and rearranging one letter at each step.	Medium6	GraphBFS+1	No attempts yet	2s	256 MB	Judgeable
Matryoshka DollsChoose and nest the most dolls so each doll carries its own weight plus every doll inside it.	Medium6	Dynamic programmingSorting	No attempts yet	1s	256 MB	Judgeable
RepelReach the exit from the entrance with the fewest unprotected entries onto wild squares, using Repel squares that shield a fixed number of steps.	Medium6	Shortest pathGraph	No attempts yet	1s	256 MB	Judgeable
Number Picking GameAhyeon removes interior numbers one at a time, scores each pick plus its live neighbors, and maximizes the total score.	Medium6	Dynamic programmingIntervals	No attempts yet	1s	256 MB	Judgeable
Mosquito, You Are MineCover as many of up to 32 points as possible with one circle of the given diameter and report the maximum count.	Medium6	GeometryBrute force	No attempts yet	2s	256 MB	Judgeable
Plotting PolynomialsCompute the initial forward-difference constants that let the given loop evaluate a degree-n polynomial at consecutive integers.	Medium6	MathCombinatorics	No attempts yet	2s	256 MB	Judgeable
Island BusesCount the rectangular islands, the straight bridges joining them, and the connected island groups that share one bus in each grid map.	Medium6	Union-findGraph+2	No attempts yet	2s	256 MB	Judgeable
Multi-touch gesture classificationFrom two side-by-side touch images, extract finger blobs and centers, pair the touches, and report pan, zoom, or rotation with its direction.	Medium6	SimulationGeometry+1	No attempts yet	2s	256 MB	Judgeable
Unicycle countingFind the smallest number of arithmetic progressions that leave marks exactly at the observed road positions.	Medium6	Dynamic programmingBit manipulation+2	No attempts yet	2s	256 MB	Judgeable
Choosing NumbersPick the largest number that shares no prime factor with any other number in the set.	Medium6	Number theoryBrute force	No attempts yet	2s	256 MB	Judgeable
Loopy transitCount distinct directed simple cycles in a graph of up to 9 stations, treating rotations of a loop as one.	Medium6	GraphBacktracking+1	No attempts yet	2s	256 MB	Judgeable
BricksSplit the run-length encoded brick row into the most contiguous blocks that all share one white-to-black ratio.	Medium6	GreedyPrefix sum+1	No attempts yet	6s	256 MB	Judgeable
Digi Comp IIBalls fall through a DAG of toggle switches that flip after each visit, and the task is to report the final state of every switch.	Medium6	Topological sortDynamic programming	No attempts yet	7s	256 MB	Judgeable
Finding a LineDecide whether any single line passes through at least p percent of N given points.	Medium6	ProbabilityGeometry+1	No attempts yet	4s	256 MB	Judgeable
Knapsack CollectionOver every starting slot, find the min, max, and average time to collect all bags from a rotating carousel when each pickup takes t units.	Medium6	SortingPrefix sum+1	No attempts yet	4s	512 MB	Judgeable
MAFIJAEach of N players accuses one other, and mobsters never accuse mobsters, so find the largest set with no internal accusation.	Medium6	Dynamic programmingGraph	No attempts yet	1s	256 MB	Judgeable
Dorm PartyChoose up to K building resets over N daily move-ins to minimize the sum of current occupancy counts at each arrival.	Medium6	Dynamic programmingGreedy+1	No attempts yet	1s	256 MB	Judgeable
Bob's House SiteCount the subrectangles of an N by M elevation grid whose covered cells all have equal height.	Medium6	StackMatrix+1	No attempts yet	1s	64 MB	Judgeable
Hill NumbersGiven N with up to 70 digits, count hill numbers smaller than N, or print -1 when N is not one.	Medium6	Dynamic programmingCombinatorics	No attempts yet	5s	256 MB	Judgeable
TowersFill an n by n Latin square with heights 1 to n that matches fixed cells and border visibility counts, printing the smallest solution or no.	Medium6	BacktrackingBrute force	No attempts yet	10s	256 MB	Judgeable
Gold LeafLocate the single horizontal, vertical, or 45-degree fold that explains the observed gold and bare paper pixels.	Medium6	Brute forceSimulation+1	No attempts yet	5s	256 MB	Judgeable
Increasing NumbersFor each given number, print -1 unless its digits never decrease, else count smaller integers whose digits never decrease.	Medium6	CombinatoricsDynamic programming	No attempts yet	5s	256 MB	Judgeable
Epic Win!Implement the given belief-state construction to print a rock-paper-scissors machine that beats a known opponent from any start state.	Medium6	Shortest pathGraph+2	No attempts yet	1s	256 MB	Judgeable
Christmas WheatMirko raises one shortest stalk to the next height and Slavko lowers one tallest stalk until two distinct heights remain; report the winner and both extremes.	Medium6	SortingPrefix sum+2	No attempts yet	1s	32 MB	Judgeable
Parliament Party SplitSimulate the greedy process that repeatedly moves the smallest-numbered member with at least three same-party quarrel partners to the other party.	Medium6	SimulationGraph+1	No attempts yet	1s	64 MB	Judgeable
Bulletproof Glass Testing BudgetCompute the minimum worst-case budget to find the exact breaking distance when each bullet and each broken pane costs money.	Medium6	Dynamic programming	No attempts yet	1s	256 MB	Judgeable
Web Service DependenciesCount the launch orders that place each container after all of its dependencies for each configuration.	Medium6	Dynamic programmingTopological sort+1	No attempts yet	1s	256 MB	Judgeable
Concatenating Parenthesis StringsDecide whether the given parenthesis strings can be ordered so their concatenation forms a correct bracket sequence.	Medium6	GreedySorting+1	No attempts yet	2s	128 MB	Judgeable
RLE ReplacementReplace the first occurrence of RLE string B inside RLE string A with RLE string C and print the result in RLE form.	Medium6	String matchingTwo pointers+1	No attempts yet	2s	128 MB	Judgeable
Everlasting ZeroDecide if every special command can be learned by raising skills that never decrease while respecting each upper and lower bound.	Medium6	Topological sortGraph	No attempts yet	5s	128 MB	Judgeable
ZGODANGiven a non-handsome integer with up to 1000 digits, find the nearest integer whose consecutive digits alternate between even and odd, printing both on a tie.	Medium6	GreedyString+1	No attempts yet	1s	32 MB	Judgeable
Holstein FenceEnclose the most Holsteins in an axis-aligned rectangle with no Guernsey inside, breaking ties by smallest area.	Medium6	Brute forceSorting+1	No attempts yet	1s	256 MB	Judgeable
Meeting TimeBessie and Elsie each choose a downhill route from field 1 to field N with their own edge times so both arrive at the same earliest moment.	Medium6	Dynamic programmingGraph	No attempts yet	1s	256 MB	Judgeable
Fegla's Scooter Test RideFind the fewest rooms in a directed cycle that starts and ends at the same room and visits at least one other room.	Medium6	BFSShortest path+1	No attempts yet	1s	256 MB	Judgeable
HamzawyFind the longest string that is a non-overlapping prefix, suffix, and middle substring of each given string.	Medium6	String matching	No attempts yet	1s	256 MB	Judgeable
FouadCount distinct numbers divisible by 7 formed by using each given digit exactly once with no leading zero.	Medium6	Dynamic programmingCombinatorics+1	No attempts yet	1s	256 MB	Judgeable
JOI ParkPick a distance X from square 1 to minimize C times X plus the total length of roads not fully inside the X radius.	Medium6	Shortest pathSorting+1	No attempts yet	1s	256 MB	Judgeable
Maximum Average SegmentFind the largest average over all contiguous subarrays of length at least K and print it truncated to six decimals.	Medium6	Binary searchPrefix sum	No attempts yet	1s	64 MB	Judgeable