Problems

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Total results29,423 problems

Hilbert Sort
Medium6
Recursion, Sorting+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Millionaire
Medium6
Dynamic programming, Probability+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Hovering Hornet
Medium6
Geometry, Probability+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Freight Train
Medium6
Binary search, Greedy
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
The King's Walk
Medium6
Combinatorics, Math
No attempts yet
Time limit
4s
Memory limit
256 MB
Judgeable
Museum
Medium6
Geometry, Combinatorics+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Bundles of Joy
Medium6
Dynamic programming, Tree
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Pipe cleaning
Medium6
Graph, BFS+1
No attempts yet
Time limit
7s
Memory limit
256 MB
Judgeable
Guessing Camels
Medium6
Segment tree, Sorting+1
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Black Vienna
Medium6
Brute force, Backtracking
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Saint John Festival
Medium6
Geometry, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Card Game Strategy
Medium6
Dynamic programming, Game theory
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Kimagure Cleaner
Medium6
Backtracking, Math
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Landscape Improved
Medium6
Binary search, Prefix sum
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Squeeze the Cylinders
Medium6
Dynamic programming, Geometry
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Wall Clocks
Medium6
Greedy, Intervals+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Deadlock Detection
Medium6
Greedy, Binary search+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Tray Bien
Medium6
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Slon's Expression
Medium6
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Performance Assessment 1
Medium6
String matching, Hash map+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Game of Peace
Medium6
Number theory, Math
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Special Christmas Tree
Medium6
Math, Greedy+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Equivalent Passwords
Medium6
Brute force, Hash map+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Robots and the Oil Transportation System
Medium6
Shortest path, DFS+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Frodo and the Monster
Medium6
Simulation, Number theory+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
T9
Medium6
Trie, Simulation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Skyline
Medium6
Dynamic programming
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Ants
Medium6
Math, Sorting
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Experiments with Gorlum
Medium6
Math, Simulation
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Schools
Medium6
Greedy, Sorting
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Crazy old lady
Medium6
Simulation, Brute force
No attempts yet
Time limit
2s
Memory limit
64 MB
Judgeable
Bank
Medium6
Dynamic programming, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
UFO
Medium6
Segment tree, Simulation+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Two-row table
Medium6
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Nimble
Medium6
Game theory, Bit manipulation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Largest Rectangle of Ones
Medium6
Stack, Matrix+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Eraser
Medium6
Combinatorics, Math+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Difference Graph
Medium6
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Twin Eagles
Medium6
Binary search, Math+1
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Power Outage
Medium6
Intervals, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Bubble Sort
Medium6
Segment tree, Sorting+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Multi-piano
Medium6
Hash map, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Two potato stores
Medium6
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Xorbonacci
Medium6
Math, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Max Flow
Medium6
Tree, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
High Card Low Card
Medium6
Greedy, Sorting
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Bessie's Dream
Medium6
BFS, Graph
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Build Gates
Medium6
BFS, Graph+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Fort Moo
Medium6
Prefix sum, Brute force+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Orange Shipping
Medium6
Dynamic programming, Sliding window
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Field Reduction
Medium6
Brute force, Geometry
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Closing the Farm
Medium6
Union-find, Graph
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
262144
Medium6
Dynamic programming, Intervals
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Splitting the Field
Medium6
Sorting, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
The 248 Game
Medium6
Dynamic programming, Intervals
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Round Robin Scheduler
Medium6
Sorting, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Dance Around the Clock (Large)
Medium6
Math, Simulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Password-free alphabet arrangement
Medium6
Backtracking, String matching+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
gBalloon (Small)
Medium6
Dynamic programming, Binary search
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
IP Address Summarization
Medium6
Intervals, Bit manipulation+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
IP Address Summarization (Large)
Medium6
Trie, Bit manipulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Paper folding 2
Medium6
Backtracking, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Even-Sum Sequence
Medium6
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Finding 123456789
Medium6
Dynamic programming, String matching+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Number of Strings Containing a Substring
Medium6
Dynamic programming, String matching
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Smoothing Window (Small)
Medium6
Binary search, Intervals+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
River Flow (Small)
Medium6
Brute force, Bit manipulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Pegman (Small)
Medium6
Brute force, Simulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Brattleship
Medium6
Game theory, Greedy+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Less Money, More Problems (Large)
Medium6
Greedy, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Filling a Board with N-Ominoes
Medium6
Game theory, Geometry+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Dreary Design (Large1)
Medium6
Combinatorics, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Power Levels
Medium6
Math, Brute force
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Broken Calculator (Large)
Medium6
Dynamic programming, Number theory
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
New Year's Eve Wine Pyramid
Medium6
Simulation, Dynamic programming
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Addition (Small)
Medium6
Union-find, Graph+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Checkable Additions
Medium6
Union-find, Graph
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Cut Tiles (Large)
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Checkerboard Matrix (Large)
Medium6
Matrix, Greedy+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Power Swapper (Small)
Medium6
Backtracking, Brute force+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Symmetric Trees (Small)
Medium6
Brute force, Tree+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Paradox Sort (Small)
Medium6
Graph, Brute force+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Magical, Marvelous Tour
Medium6
Prefix sum, Two pointers
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Magical, Marvelous Tour
Medium6
Binary search, Prefix sum
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Last Hit (Small)
Medium6
Dynamic programming, Game theory+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Last Hit
Medium6
Dynamic programming, Math
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Crime House (Small)
Medium6
Backtracking, Simulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Crime House (Large)
Medium6
Greedy, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
The Bored Traveling Salesman (Small)
Medium6
Backtracking, DFS+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Charging Chaos (Large)
Medium6
Bit manipulation, Hash map+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Deceitful War (Small)
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Deceitful War (Large)
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Meet and Party (Large)
Medium6
Sorting, Prefix sum+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Hex (Large)
Medium6
Graph, BFS+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Rational Number Tree
Medium6
Math, Number theory+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
X Marks the Spot
Medium6
Geometry, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Can't Stop (Small)
Medium6
Sliding window, Backtracking
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Rigged Roulette
Medium6
Probability, Math+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Multiplayer Pong (Small)
Medium6
Simulation, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Falling Diamonds (Small)
Medium6
Probability, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Hilbert SortSort up to 200,000 labeled grid points by the order in which the Hilbert curve visits them.	Medium6	RecursionSorting+1	No attempts yet	5s	256 MB	Judgeable
MillionaireDecide after each correct quiz answer whether to quit or continue so the expected log utility is maximal, then convert that utility into a dollar amount.	Medium6	Dynamic programmingProbability+1	No attempts yet	2s	256 MB	Judgeable
Hovering HornetExpected number of spots on a die visible from a random point in its box, counting a spot only when the segment to the viewer misses the die.	Medium6	GeometryProbability+1	No attempts yet	1s	512 MB	Judgeable
Freight TrainPartition the train into at most L consecutive groups covering every loaded wagon with a Luxembourg-bound group while minimizing the longest such group.	Medium6	Binary searchGreedy	No attempts yet	2s	256 MB	Judgeable
The King's WalkCount how many shortest king-move paths join two given squares on an N by N board, modulo 5318008.	Medium6	CombinatoricsMath	No attempts yet	4s	256 MB	Judgeable
MuseumCount triples of wall pillars that form a triangle none of whose sides crosses the square pedestal.	Medium6	GeometryCombinatorics+1	No attempts yet	2s	256 MB	Judgeable
Bundles of JoyBuy the cheapest set of nested or disjoint bundles that covers every dessert type.	Medium6	Dynamic programmingTree	No attempts yet	3s	256 MB	Judgeable
Pipe cleaningDecide whether a subset of pipes covers every pipe crossing with exactly one of the two crossing pipes chosen.	Medium6	GraphBFS+1	No attempts yet	7s	256 MB	Judgeable
Guessing CamelsCount the camel pairs ranked in the same relative order in all three given bets.	Medium6	Segment treeSorting+1	No attempts yet	10s	512 MB	Judgeable
Black ViennaCount the three-suspect sets that can form the hidden circle while matching every investigation reply about the two players' hands.	Medium6	Brute forceBacktracking	No attempts yet	1s	256 MB	Judgeable
Saint John FestivalCount how many small lantern points fall inside or on the boundary of the convex hull of the large lantern points.	Medium6	GeometrySorting+1	No attempts yet	1s	256 MB	Judgeable
Card Game StrategyAlice picks t in [a, b] to maximize the gap while Bob replies with k cards whose sum is closest to t.	Medium6	Dynamic programmingGame theory	No attempts yet	5s	1024 MB	Judgeable
Kimagure CleanerFill in the forgotten turns and pick each run length inside its range so the cleaner ends at (X, Y), printing the smallest such log.	Medium6	BacktrackingMath	No attempts yet	10s	1024 MB	Judgeable
Landscape ImprovedPlace up to n stones on a rocky skyline under pyramid support rules to push the highest peak as high as possible.	Medium6	Binary searchPrefix sum	No attempts yet	1s	256 MB	Judgeable
Squeeze the CylindersGiven up to 500 ground-resting cylinders with fixed order, compute the minimum wall-to-wall width when squeezed together.	Medium6	Dynamic programmingGeometry	No attempts yet	1s	256 MB	Judgeable
Wall ClocksEach member sees a section of the office walls inside a 90 degree cone, and the task asks for the fewest clock points so every member sees at least one.	Medium6	GreedyIntervals+1	No attempts yet	1s	256 MB	Judgeable
Deadlock DetectionGiven each process resource needs and the allocation log, find the earliest time when deadlock becomes unavoidable, or print -1.	Medium6	GreedyBinary search+1	No attempts yet	2s	256 MB	Judgeable
Tray BienCount the ways to cover a 3 by m shelf with blocked cells using 1 by 1 and domino trays, where only the domino pairings distinguish arrangements.	Medium6	Dynamic programming	No attempts yet	1s	256 MB	Judgeable
Slon's ExpressionParse a linear expression in x and find the smallest non-negative x with the expression congruent to P modulo M.	Medium6	Number theoryMath+1	No attempts yet	1s	64 MB	Judgeable
Performance Assessment 1Find the shortest sequence over 1 to M missing as a contiguous block of A and count such sequences modulo 1e9+7.	Medium6	String matchingHash map+1	No attempts yet	1s	256 MB	Judgeable
Game of PeaceCompute the gcd of the two container sizes after M cloning steps with Y extra marbles added to the larger container after step N.	Medium6	Number theoryMath	No attempts yet	3s	256 MB	Judgeable
Special Christmas TreeFind the maximum node count of a binary tree with exactly L leaves and height at most H.	Medium6	MathGreedy+1	No attempts yet	3s	256 MB	Judgeable
Equivalent PasswordsGiven an ordered list of short numeric passwords, find the worst-case number typed when passwords equivalent to an earlier typed one are skipped.	Medium6	Brute forceHash map+1	No attempts yet	3s	256 MB	Judgeable
Robots and the Oil Transportation SystemTwo robots start at given stations and cover opposite ends of one trunk pipe, minimizing the slower robot travel time.	Medium6	Shortest pathDFS+1	No attempts yet	2s	256 MB	Judgeable
Frodo and the MonsterSimulate up to 200000 cuts on the head count where odd cuts add the largest smaller prime and even cuts remove every head with the same binary popcount.	Medium6	SimulationNumber theory+2	No attempts yet	1s	256 MB	Judgeable
T9Simulate T9 predictive text: map digit presses to dictionary words ordered by frequency, cycle candidates with star, and update frequencies on accept.	Medium6	TrieSimulation+1	No attempts yet	1s	256 MB	Judgeable
SkylineBuild N towers to exact heights with 1, 2-adjacent and 3-consecutive floor operations costing 3, 5 and 7 for the least total cost.	Medium6	Dynamic programming	No attempts yet	2s	256 MB	Judgeable
AntsSimulate K ants that bounce off the walls of a W by H field and reverse on head-on meetings for T seconds, then report each ant position and direction.	Medium6	MathSorting	No attempts yet	2s	256 MB	Judgeable
Experiments with GorlumA creature repeats a move string K times and you report the smallest and largest squared distances from a laser over all visited points.	Medium6	MathSimulation	No attempts yet	1s	64 MB	Judgeable
SchoolsChoose M cities for music schools and S other cities for sports schools to maximize the total number of attending students.	Medium6	GreedySorting	No attempts yet	2s	256 MB	Judgeable
Crazy old ladyFrom the recorded boarding seats under the displaced-passenger rule, recover the first boarder's assigned seat if it is unique and print 0 otherwise.	Medium6	SimulationBrute force	No attempts yet	2s	64 MB	Judgeable
BankDecide whether M banknotes can be distributed to N people so each person receives exactly the owed salary.	Medium6	Dynamic programmingBit manipulation	No attempts yet	1s	256 MB	Judgeable
UFOSimulate laser shots that each destroy up to R blocks at height h along one row or column, then find the P by P square holding the most surviving blocks.	Medium6	Segment treeSimulation+1	No attempts yet	2s	256 MB	Judgeable
Two-row tableCount ways to place fixed and shared numbers into two increasing rows so every column increases downward.	Medium6	Dynamic programmingCombinatorics	No attempts yet	1s	256 MB	Judgeable
NimbleEach turn slides one coin left along numbered squares, so print which player moves the last coin onto square zero under optimal play.	Medium6	Game theoryBit manipulation	No attempts yet	2s	512 MB	Judgeable
Largest Rectangle of OnesFind the area of the largest all-ones subrectangle in each binary matrix given until 0 0.	Medium6	StackMatrix+1	No attempts yet	3s	512 MB	Judgeable
EraserGiven a sequence, add the products of every triple of entries at distinct positions with three different values, modulo 1,000,000,007.	Medium6	CombinatoricsMath+1	No attempts yet	1s	256 MB	Judgeable
Difference GraphAnswer many shortest-path queries on a directed graph where the cost of an edge from u to v depends only on the difference of the vertices modulo N.	Medium6	Shortest pathGraph+1	No attempts yet	1s	32 MB	Judgeable
Twin EaglesFind the fewest days for two eagles dealing LH damage per attack to kill a lion and a bear that heal each night, or output -1.	Medium6	Binary searchMath+1	No attempts yet	1s	32 MB	Judgeable
Power OutageDecide which lamps run in blackouts to maximize the road length lit both normally and during blackouts.	Medium6	IntervalsSorting+1	No attempts yet	1s	256 MB	Judgeable
Bubble SortCompute the array after K left-to-right bubble sort passes over N numbers without simulating every swap.	Medium6	Segment treeSorting+1	No attempts yet	1s	64 MB	Judgeable
Multi-pianoChoose a nonnegative step K so the walk that starts at the first pitch and moves by K on each rise or fall matches the true pitches in the most positions.	Medium6	Hash mapPrefix sum+1	No attempts yet	1s	64 MB	Judgeable
Two potato storesSplit N potato bags into two stores with one store holding exactly L bags to minimize the product of the two average potato prices.	Medium6	Dynamic programming	No attempts yet	1s	64 MB	Judgeable
XorbonacciGiven the first K terms of an XOR recurrence, answer many queries asking for the XOR of terms l through r with indices up to 1e18.	Medium6	MathPrefix sum+1	No attempts yet	1s	64 MB	Judgeable
Max FlowCount how many of the K given tree paths pass through each stall and report the largest count.	Medium6	TreePrefix sum+1	No attempts yet	2s	512 MB	Judgeable
High Card Low CardOrder Bessie's cards against Elsie's known sequence to win the most rounds under high-card-first-half and low-card-second-half scoring.	Medium6	GreedySorting	No attempts yet	2s	512 MB	Judgeable
Bessie's DreamFind the fewest moves across a colored grid where orange tiles grant a scent, blue tiles need it, and purple tiles force a slide.	Medium6	BFSGraph	No attempts yet	2s	512 MB	Judgeable
Build GatesCount the enclosed regions formed by a walk of up to 1000 unit steps, as each enclosed region needs one gate to reconnect the farm.	Medium6	BFSGraph+1	No attempts yet	2s	512 MB	Judgeable
Fort MooFind the largest interior area of a grid rectangle whose border cells are all grass, with swamp allowed inside.	Medium6	Prefix sumBrute force+1	No attempts yet	2s	512 MB	Judgeable
Orange ShippingPartition the ordered oranges into consecutive boxes of at most M to minimize the sum of K plus size times the size spread in each box.	Medium6	Dynamic programmingSliding window	No attempts yet	1s	256 MB	Judgeable
Field ReductionRemove up to three of N points so the axis-aligned bounding rectangle of the rest has the smallest possible area.	Medium6	Brute forceGeometry	No attempts yet	2s	512 MB	Judgeable
Closing the FarmAfter each barn closure in the given order, report whether the remaining open barns stay connected by open paths.	Medium6	Union-findGraph	No attempts yet	2s	512 MB	Judgeable
262144Merge adjacent equal numbers into a number one larger in any order to build the largest value possible.	Medium6	Dynamic programmingIntervals	No attempts yet	2s	512 MB	Judgeable
Splitting the FieldCompute how much fenced area is saved by covering all points with two disjoint axis-aligned rectangles instead of one.	Medium6	SortingPrefix sum+1	No attempts yet	2s	512 MB	Judgeable
The 248 GameMerge adjacent equal numbers into a number one larger to maximize the largest value left.	Medium6	Dynamic programmingIntervals	No attempts yet	2s	512 MB	Judgeable
Round Robin SchedulerGiven each job's required seconds, compute its finishing time under a round robin scheduler that grants one second per turn in index order.	Medium6	SortingPrefix sum+1	No attempts yet	2s	512 MB	Judgeable
Dance Around the Clock (Large)After N alternating pairwise swaps around a circle of D dancers, report the two neighbors of dancer K.	Medium6	MathSimulation	No attempts yet	5s	512 MB	Judgeable
Password-free alphabet arrangementArrange A to Z in one row so none of the given passwords appears as a contiguous block, choosing the smallest such order or reporting impossibility.	Medium6	BacktrackingString matching+1	No attempts yet	5s	512 MB	Judgeable
gBalloon (Small)Spend at most Q height-change energy across balloons with layered winds to minimize the time when the last balloon reaches position 0.	Medium6	Dynamic programmingBinary search	No attempts yet	5s	512 MB	Judgeable
IP Address SummarizationMerge the given IPv4 subnets and print the shortest ordered list of normalized subnets that covers exactly the same addresses.	Medium6	IntervalsBit manipulation+2	No attempts yet	5s	512 MB	Judgeable
IP Address Summarization (Large)The task merges the given IPv4 subnets into the shortest sorted list of normalized subnets covering exactly the same addresses.	Medium6	TrieBit manipulation+1	No attempts yet	5s	512 MB	Judgeable
Paper folding 2Fold a 6 by 6 or smaller number grid along grid lines so overlapping cells add up, and maximize the value held in one cell.	Medium6	BacktrackingBrute force+1	No attempts yet	1s	128 MB	Judgeable
Even-Sum SequenceReplace the fewest entries so every length-k window sum is even, then output the lexicographically smallest such sequence.	Medium6	MathGreedy	No attempts yet	1s	256 MB	Judgeable
Finding 123456789Count subsets of occurrences of P in S whose starting positions multiply to a common multiple of 1 through 9, modulo 1000000007.	Medium6	Dynamic programmingString matching+1	No attempts yet	1s	512 MB	Judgeable
Number of Strings Containing a SubstringCount length-L lowercase strings that contain the given word S as a contiguous substring, modulo 1,000,000,009.	Medium6	Dynamic programmingString matching	No attempts yet	2s	512 MB	Judgeable
Smoothing Window (Small)Given sliding window sums of an unknown integer sequence, find the smallest possible range between its largest and smallest values.	Medium6	Binary searchIntervals+1	No attempts yet	5s	512 MB	Judgeable
River Flow (Small)Find the fewest farmers whose power-of-two toggling cycles explain N days of river flow, or declare the record impossible.	Medium6	Brute forceBit manipulation+1	No attempts yet	5s	512 MB	Judgeable
Pegman (Small)Change as few arrows as possible so a walker following arrows from any start cell never leaves the grid.	Medium6	Brute forceSimulation	No attempts yet	5s	512 MB	Judgeable
BrattleshipFind the fewest guesses that guarantee sinking a hidden 1 by W ship on an R by C board when an adversary relocates it to fit past answers.	Medium6	Game theoryGreedy+1	No attempts yet	5s	512 MB	Judgeable
Less Money, More Problems (Large)Add the fewest new coin denominations so every value up to V is payable with at most C coins of each denomination.	Medium6	GreedyMath	No attempts yet	5s	512 MB	Judgeable
Filling a Board with N-OminoesFor each case with piece size X and board R by C, decide whether Richard has an X-omino that blocks every tiling or Gabriel tiles the board anyway.	Medium6	Game theoryGeometry+1	No attempts yet	5s	512 MB	Judgeable
Dreary Design (Large1)Count RGB triples with each component between 0 and K whose largest and smallest values differ by at most V.	Medium6	CombinatoricsMath	No attempts yet	5s	512 MB	Judgeable
Power LevelsGiven only the digit count D of a hidden integer, find the fewest exclamation marks E making the multifactorial of 9000 certainly smaller than it.	Medium6	MathBrute force	No attempts yet	5s	512 MB	Judgeable
Broken Calculator (Large)Find the fewest digit, multiply, and equals presses that form factors whose product equals X using only working digits.	Medium6	Dynamic programmingNumber theory	No attempts yet	5s	512 MB	Judgeable
New Year's Eve Wine PyramidSimulate B bottles poured into the top glass of a wine pyramid where overflow splits into three glasses below and report the amount in glass N on level L.	Medium6	SimulationDynamic programming	No attempts yet	5s	512 MB	Judgeable
Addition (Small)You decide which pair sums follow from the surviving equations and print each forced sum in input order.	Medium6	Union-findGraph+1	No attempts yet	5s	512 MB	Judgeable
Checkable AdditionsFrom recorded equations of the form x+y=z, report each queried pair sum forced to one value by them.	Medium6	Union-findGraph	No attempts yet	5s	512 MB	Judgeable
Cut Tiles (Large)Pack square tiles with power-of-two sides into the fewest MxM tiles using only side-parallel cuts.	Medium6	GreedySorting+1	No attempts yet	5s	512 MB	Judgeable
Checkerboard Matrix (Large)Find the fewest row and column swaps that turn the given binary matrix into a checkerboard, or report IMPOSSIBLE.	Medium6	MatrixGreedy+1	No attempts yet	5s	512 MB	Judgeable
Power Swapper (Small)Count the ordered swap sequences that sort the permutation when each block size is used at most once on aligned ranges.	Medium6	BacktrackingBrute force+1	No attempts yet	5s	512 MB	Judgeable
Symmetric Trees (Small)Decide whether a colored tree with at most 12 vertices admits a planar straight-line drawing with a vertical line of symmetry.	Medium6	Brute forceTree+1	No attempts yet	5s	512 MB	Judgeable
Paradox Sort (Small)Find the lexicographically smallest candy order whose sequential pairwise elimination leaves candy A standing, or report IMPOSSIBLE.	Medium6	GraphBrute force+1	No attempts yet	5s	512 MB	Judgeable
Magical, Marvelous TourArnar picks a contiguous segment, Solveig claims the largest of the three parts it creates, and Arnar keeps the rest.	Medium6	Prefix sumTwo pointers	No attempts yet	5s	512 MB	Judgeable
Magical, Marvelous TourArnar names a middle interval and Solveig keeps the richest of the three pieces, so compute the split that leaves Arnar the most transistors.	Medium6	Binary searchPrefix sum	No attempts yet	5s	512 MB	Judgeable
Last Hit (Small)Choose which monster to shoot or when to pass on each turn so your shots land the killing blow on the most valuable monsters before the tower kills them.	Medium6	Dynamic programmingGame theory+1	No attempts yet	5s	512 MB	Judgeable
Last HitChoose which monsters to last-hit for gold while a tower shoots the closest living monster on its own turns.	Medium6	Dynamic programmingMath	No attempts yet	10s	512 MB	Judgeable
Crime House (Small)Assign each masked passage to a person so inside and outside states stay valid and report the smallest possible final occupancy, or CRIME TIME.	Medium6	BacktrackingSimulation	No attempts yet	5s	512 MB	Judgeable
Crime House (Large)Decide if an enter and leave log with masked identities fits a single door and find the smallest possible number of people left inside.	Medium6	GreedySimulation+1	No attempts yet	5s	512 MB	Judgeable
The Bored Traveling Salesman (Small)Choose a start city and a depth-first ticket tour of the graph so the concatenated first-visit ZIP codes form the smallest number.	Medium6	BacktrackingDFS+1	No attempts yet	5s	512 MB	Judgeable
Charging Chaos (Large)Find a bit mask applied to every outlet string that makes the outlet set match the device set with the fewest flipped bits, or report that it is impossible.	Medium6	Bit manipulationHash map+1	No attempts yet	5s	512 MB	Judgeable
Deceitful War (Small)Given both players' block weights, compute Naomi's best scores under honest War rules and under optimal lying in Deceitful War.	Medium6	GreedySorting+1	No attempts yet	5s	512 MB	Judgeable
Deceitful War (Large)Given both players' block weights, compute Naomi's optimal scores under honest play and under bluffed announcements.	Medium6	GreedySorting+1	No attempts yet	5s	512 MB	Judgeable
Meet and Party (Large)Pick an invited home inside the given rectangles that minimizes the total Manhattan distance walked by all guests and report its coordinates and the sum.	Medium6	SortingPrefix sum+1	No attempts yet	5s	512 MB	Judgeable
Hex (Large)Decide whether an N by N Hex board is impossible, won by Red, won by Blue, or still undecided.	Medium6	GraphBFS+1	No attempts yet	5s	512 MB	Judgeable
Rational Number TreeGiven the infinite binary tree that lists every positive rational once, find the nth fraction in level order and the level-order position of a given fraction.	Medium6	MathNumber theory+2	No attempts yet	5s	512 MB	Judgeable
X Marks the SpotFind the shortest integer direction so two movable perpendicular lines split the 4N points into four groups of N each.	Medium6	GeometrySorting+1	No attempts yet	5s	512 MB	Judgeable
Can't Stop (Small)Find the longest consecutive run of roll sets where every set contains at least one of k chosen numbers.	Medium6	Sliding windowBacktracking	No attempts yet	5s	512 MB	Judgeable
Rigged RouletteChoose integer bets within a budget on roulette numbers so the rigged wheel favors the least-bet numbers and expected profit is as large as possible.	Medium6	ProbabilityMath+1	No attempts yet	5s	512 MB	Judgeable
Multiplayer Pong (Small)Decide which pong team misses first, or draws, from wall bounce heights with paddle speed limits and a fixed return order.	Medium6	SimulationMath	No attempts yet	5s	512 MB	Judgeable
Falling Diamonds (Small)N diamonds fall onto a pile and slide left or right at random, and you compute the probability that one stops exactly at the given spot.	Medium6	ProbabilitySimulation+1	No attempts yet	5s	512 MB	Judgeable