Problems

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Total results29,453 problems

Gimli's Gullet
Medium5
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
The Magic Word
Medium5
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Delicious Cookie
Medium5
Combinatorics, Geometry+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Formula Equivalence
Medium5
Brute force, Recursion
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Race Map Labeling
Medium5
Simulation, Graph
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Population Migration
Medium5
Simulation, Sorting
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Sum of odd-indexed Fibonacci numbers
Medium5
Math, Matrix+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Sum of Even-Indexed Fibonacci Numbers
Medium5
Matrix, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cheating Knight
Medium5
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Song Titles
Medium5
Greedy, Heap+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Falcon Dive
Medium5
Matrix, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Easy Arithmetic
Medium5
Greedy, String
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Insider's Information
Medium5
Simulation, Greedy+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Number of distinct substrings
Medium5
String matching, Hash map+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Jumping Across Logs
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Kinfolk
Medium5
Tree, Math+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Refract Facts
Medium5
Binary search, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Poker
Medium5
Implementation, Sorting
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Boggle
Medium5
Backtracking, Trie+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Running Steps
Medium5
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
A Rational Sequence
Medium5
Math, Tree+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Pyro Tubes
Medium5
Bit manipulation, Hash map
No attempts yet
Time limit
13s
Memory limit
256 MB
Judgeable
Each digit at most twice
Medium5
Backtracking, Greedy+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
From Sinchon to Anam
Medium5
Geometry, Brute force
No attempts yet
Time limit
7s
Memory limit
256 MB
Judgeable
Fraction to Repeating Decimal
Medium5
Hash map, Math+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Condition of deep sleep
Medium5
Greedy, Sliding window
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
That set is a harmful set
Medium5
Math, Simulation
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Checkers
Medium5
Backtracking, DFS+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Surf
Medium5
Dynamic programming, Sorting+1
No attempts yet
Time limit
4s
Memory limit
256 MB
Judgeable
Gears
Medium5
Graph, BFS+1
No attempts yet
Time limit
4s
Memory limit
256 MB
Judgeable
Map Colouring
Medium5
Backtracking, Graph
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Flipping Cards
Medium5
Graph, Union-find
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
The Magical 3
Medium5
Number theory, Math
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Matrix Keypad
Medium5
Matrix, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Checkers
Medium5
Backtracking, DFS
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Number of solutions
Medium5
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Workstation assignment
Medium5
Greedy, Heap+1
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Canvas Painting
Medium5
Greedy, Heap
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Sheldon Numbers
Medium5
Brute force, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Factorial Trailing Zeros
Medium5
Binary search, Math
No attempts yet
Time limit
0.5s
Memory limit
256 MB
Judgeable
LCM of 1 through n
Medium5
Number theory, Math
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Sum of divisors of n^m
Medium5
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
KenKen You Do It?
Medium5
Backtracking, Brute force
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Minimum Cost Route
Medium5
Shortest path, Heap
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
All Pairs Shortest Routes
Medium5
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Feast Coins
Medium5
Dynamic programming, Combinatorics
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Messed Up Pictures
Medium5
Math, Brute force
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Alphabet on a Circle
Medium5
Math, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
64 MB
Judgeable
K-ary Tree
Medium5
Tree, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Black-and-white Square
Medium5
Matrix, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
King's Walk
Medium5
Dynamic programming, Matrix
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Fan migration
Medium5
Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Hyper-minimum
Medium5
Sliding window, Queue
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Riddick's Cube
Medium5
Brute force, Simulation+1
No attempts yet
Time limit
2s
Memory limit
64 MB
Judgeable
Maximal Area
Medium5
Stack, Array
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Perica's Piano
Medium5
Combinatorics, Sorting+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
The Ant Robot
Medium5
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Deception
Medium5
Bit manipulation, Greedy
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Preserving the Grid
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
A Strange Sequence
Medium5
Simulation, Hash map+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
What a Twist
Medium5
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Zombies
Medium5
Shortest path, BFS+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Happy Numbers
Medium5
Number theory, Prefix sum+1
No attempts yet
Time limit
0.5s
Memory limit
64 MB
Judgeable
Fruit Feast
Medium5
Dynamic programming
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Turning on the lights
Medium5
BFS, Graph
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Radio Contact
Medium5
Dynamic programming
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Load Balancing
Medium5
Sorting, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Circular Barn (Silver)
Medium5
Dynamic programming, Brute force
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Load Balancing
Medium5
Brute force, Sorting
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Diamond Collector
Medium5
Sorting, Two pointers
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Field Reduction
Medium5
Brute force, Geometry
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Closing the Farm
Medium5
Union-find, Graph
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Cleaning the Club Room!
Medium5
Dynamic programming, Prefix sum
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
LU decomposition of a band matrix
Medium5
Matrix, Math+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Pairing
Medium5
Greedy, Simulation+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Counting four cycles
Medium5
Graph, Combinatorics+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Mr. Kim's Grocery Store (Small)
Medium5
Greedy, Hash map+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Kim Incheon's Grocery Store (Large)
Medium5
Greedy, Hash map+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Robot Rock Band (Small)
Medium5
Hash map, Brute force
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Robot Rock Band (Large)
Medium5
Hash map, Bit manipulation
No attempts yet
Time limit
7s
Memory limit
512 MB
Judgeable
Not So Random
Medium5
Probability, Bit manipulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Not So Random (Large)
Medium5
Bit manipulation, Probability+1
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Virtual Rabbit (Small)
Medium5
Greedy, Intervals
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Total File Count
Medium5
Math, Intervals+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
How Many Files
Medium5
Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Elf Tournament Bracket
Medium5
Brute force, Implementation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Sum of submatrix maxima
Medium5
Sliding window, Matrix+1
No attempts yet
Time limit
20s
Memory limit
1024 MB
Judgeable
Googol String (Large)
Medium5
Recursion, Bit manipulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
gCube (Large)
Medium5
Prefix sum, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
gCampus (Large)
Medium5
Shortest path, Graph
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
2048 (Hard)
Medium5
Brute force, Backtracking+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Lunch Menu
Medium5
Segment tree, Sorting+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
2048 (Easy)
Medium5
Brute force, Backtracking+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Tournament
Medium5
Sorting, Math
No attempts yet
Time limit
3s
Memory limit
64 MB
Judgeable
Fairland (Small)
Medium5
Tree, DFS+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Pegman
Medium5
Greedy, Simulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Typewriter Monkey (Small)
Medium5
Probability, Brute force+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Typewriter Monkey
Medium5
Probability, String matching
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Counter Culture (Small)
Medium5
BFS, Graph
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Haircut Queue
Medium5
Binary search, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Gimli's GulletPack unlimited servings of M foods into capacity C for the most calories, breaking ties by the lexicographically smallest serving counts.	Medium5	Dynamic programming	No attempts yet	1s	256 MB	Judgeable
The Magic WordInterpret a spell of up to 200 lines with variables, arrays, jumps, and prints, and reproduce its output.	Medium5	SimulationImplementation	No attempts yet	1s	256 MB	Judgeable
Delicious CookieSplit every piece of a right triangle with legs a and b N times along the altitude to the hypotenuse and print the natural log of the K-th largest piece area.	Medium5	CombinatoricsGeometry+1	No attempts yet	1s	512 MB	Judgeable
Formula EquivalenceDecide whether two Boolean formulas with AND, OR, and NOT over at most 16 variables agree on every truth assignment.	Medium5	Brute forceRecursion	No attempts yet	1s	256 MB	Judgeable
Race Map LabelingSimulate the smallest-first label-flipping process on the graph and print every place with its final label.	Medium5	SimulationGraph	No attempts yet	2s	256 MB	Judgeable
Population MigrationResidents buy each job from the priciest affordable worker and leave when daily income falls below outside earnings; count who stays once departures stop.	Medium5	SimulationSorting	No attempts yet	5s	256 MB	Judgeable
Sum of odd-indexed Fibonacci numbersGiven n up to 1e18, compute the sum of odd-indexed Fibonacci numbers from F_0 to F_n modulo 1,000,000,007.	Medium5	MathMatrix+1	No attempts yet	1s	256 MB	Judgeable
Sum of Even-Indexed Fibonacci NumbersGiven n, add the Fibonacci numbers at even indices from 0 to n and print the sum modulo 1000000007.	Medium5	MatrixMath	No attempts yet	1s	256 MB	Judgeable
Cheating KnightA knight whose jumps of fixed length may land on any point of the plane must reach a target square in the fewest jumps.	Medium5	GeometryMath	No attempts yet	1s	256 MB	Judgeable
Song TitlesRearrange each title into the lexicographically smallest anagram with no equal adjacent letters, or report IMPOSSIBLE when none exists.	Medium5	GreedyHeap+1	No attempts yet	1s	256 MB	Judgeable
Falcon DiveShift the falcon silhouette by its frame-to-frame displacement and draw it over the shared background as a third frame.	Medium5	MatrixImplementation	No attempts yet	1s	256 MB	Judgeable
Easy ArithmeticInsert extra plus and minus signs between the digits of the given expression so the resulting valid expression has the largest possible value.	Medium5	GreedyString	No attempts yet	2s	256 MB	Judgeable
Insider's InformationFollow the given removal order, then insert each university at the front or back to satisfy at least half the betweenness triples.	Medium5	SimulationGreedy+2	No attempts yet	2s	256 MB	Judgeable
Number of distinct substringsCount how many different contiguous substrings appear in a lowercase string of length up to 1000.	Medium5	String matchingHash map+1	No attempts yet	1s	512 MB	Judgeable
Jumping Across LogsArrange the given log heights in a circle to minimize the largest height gap between neighbors.	Medium5	GreedySorting	No attempts yet	1s	256 MB	Judgeable
KinfolkGiven two positions in a binary family tree and the second person's gender, print the English kinship term of the second to the first.	Medium5	TreeMath+1	No attempts yet	1s	256 MB	Judgeable
Refract FactsGiven the submarine depth, jet height, horizontal distance and refraction indices, compute the laser elevation angle that hits the jet after refraction.	Medium5	Binary searchMath	No attempts yet	1s	256 MB	Judgeable
PokerCompare two five-card poker hands by standard rankings and kicker tiebreakers and print the winning hand or Tie.	Medium5	ImplementationSorting	No attempts yet	1s	256 MB	Judgeable
BoggleFind every dictionary word that can be spelled on each letter grid with adjacent cells and no cell reused, treating q as qu.	Medium5	BacktrackingTrie+1	No attempts yet	1s	256 MB	Judgeable
Running StepsCount left-right alternating sequences of one-step and two-step strides where both legs use equal counts and twos are at least as many as ones.	Medium5	CombinatoricsMath	No attempts yet	1s	256 MB	Judgeable
A Rational SequenceGiven a reduced fraction p/q from the Calkin-Wilf tree, compute its position n in breadth-first order.	Medium5	MathTree+1	No attempts yet	1s	256 MB	Judgeable
Pyro TubesFor each value in a sorted list, count larger list values whose 18-bit patterns differ in at most two bits.	Medium5	Bit manipulationHash map	No attempts yet	13s	256 MB	Judgeable
Each digit at most twiceFind the largest integer L not greater than U whose decimal digits each appear at most twice.	Medium5	BacktrackingGreedy+1	No attempts yet	3s	256 MB	Judgeable
From Sinchon to AnamFind the shortest single segment that connects the Sinchon road network to the Anam road network.	Medium5	GeometryBrute force	No attempts yet	7s	256 MB	Judgeable
Fraction to Repeating DecimalWrite each given fraction as its decimal form with the shortest nonrepeating part and the repeating block in parentheses.	Medium5	Hash mapMath+1	No attempts yet	1s	256 MB	Judgeable
Condition of deep sleepTurn all N bulbs off with flips of exactly K consecutive bulbs using the fewest presses, or report Insomnia when it is impossible.	Medium5	GreedySliding window	No attempts yet	1s	256 MB	Judgeable
That set is a harmful setFor each rational a/b, print the smallest n from 0 to 10 whose stage set misses it, or -1 when all eleven contain it.	Medium5	MathSimulation	No attempts yet	3s	256 MB	Judgeable
CheckersFind the Black piece that captures every White piece in one chained jump, or report Multiple or None.	Medium5	BacktrackingDFS+1	No attempts yet	2s	256 MB	Judgeable
SurfPick waves with no wait-time overlap so the sum of fun points is as large as possible.	Medium5	Dynamic programmingSorting+1	No attempts yet	4s	256 MB	Judgeable
GearsGears that touch drive each other in opposite directions at inverse radius ratios; report the reduced ratio of the last gear to the first, or a jam or no link.	Medium5	GraphBFS+1	No attempts yet	4s	256 MB	Judgeable
Map ColouringColor each map with the fewest colors so bordering countries differ and print 1 to 4, or many when more are needed.	Medium5	BacktrackingGraph	No attempts yet	5s	256 MB	Judgeable
Flipping CardsDecide whether each card can show one of its two pictures so that all n face-up pictures differ.	Medium5	GraphUnion-find	No attempts yet	3s	256 MB	Judgeable
The Magical 3Given n, find the smallest base above 3 in which n ends in digit 3, or report that none exists.	Medium5	Number theoryMath	No attempts yet	3s	256 MB	Judgeable
Matrix KeypadFrom a binary grid that records the AND of pressed rows and columns, mark each button as pressed in none, all, or only some of the press sets that fit the grid.	Medium5	MatrixImplementation	No attempts yet	1s	256 MB	Judgeable
CheckersCount the black kings that can capture all white kings in one chain of diagonal jumps.	Medium5	BacktrackingDFS	No attempts yet	2s	256 MB	Judgeable
Number of solutionsCount the integer pairs (x, y) inside the given x and y ranges that satisfy Ax + By + C = 0.	Medium5	Number theoryMath	No attempts yet	1s	256 MB	Judgeable
Workstation assignmentSeat each arriving researcher at a freed workstation that stayed unlocked to save the most unlocks.	Medium5	GreedyHeap+1	No attempts yet	10s	256 MB	Judgeable
Canvas PaintingArrange the canvases in a line and repeatedly split one color group into two so every canvas ends with its own color at the smallest total repaint cost.	Medium5	GreedyHeap	No attempts yet	1s	256 MB	Judgeable
Sheldon NumbersCount numbers between X and Y whose binary form starts with ones and alternates blocks of N ones and M zeros.	Medium5	Brute forceBit manipulation+1	No attempts yet	1s	256 MB	Judgeable
Factorial Trailing ZerosFind the smallest N whose factorial has exactly M trailing zeros, or print -1 when no such N exists.	Medium5	Binary searchMath	No attempts yet	0.5s	256 MB	Judgeable
LCM of 1 through nCompute the least common multiple of all integers from 1 to n (n up to 10^8) and print it modulo 2^32.	Medium5	Number theoryMath	No attempts yet	2s	256 MB	Judgeable
Sum of divisors of n^mGiven n and m, compute the sum of all divisors of n to the power m modulo 1000000007.	Medium5	Number theoryMath	No attempts yet	1s	256 MB	Judgeable
KenKen You Do It?Count the assignments of numbers 1 to n to the given cage cells that meet the target under the operator with distinct values in shared rows and columns.	Medium5	BacktrackingBrute force	No attempts yet	2s	256 MB	Judgeable
Minimum Cost RouteFind the cheapest bus fare from city A to city B and print the fare, the city count, and the path, preferring fewer cities and then lexicographic order on ties.	Medium5	Shortest pathHeap	No attempts yet	1s	256 MB	Judgeable
All Pairs Shortest RoutesFind the cheapest fare between every pair of cities and print each cheapest route, breaking ties by lexicographic order.	Medium5	Shortest pathGraph	No attempts yet	1s	256 MB	Judgeable
Feast CoinsCount ways to reach total S with owned coins so that every chosen coin value appears the same number of times.	Medium5	Dynamic programmingCombinatorics	No attempts yet	3s	256 MB	Judgeable
Messed Up PicturesFor each given image, find the smallest listed-ratio size that covers it directly or after a 90-degree rotation, and report the operation count.	Medium5	MathBrute force	No attempts yet	3s	256 MB	Judgeable
Alphabet on a CircleStarting at a, walk the 26-letter circle with direction flips at given points and count how often the queried letter occurs in the first n spoken letters.	Medium5	MathPrefix sum+1	No attempts yet	2s	64 MB	Judgeable
K-ary TreeCompute the edge distance for each query pair in a complete K-ary tree with N nodes numbered in breadth-first order.	Medium5	TreeMath	No attempts yet	1s	256 MB	Judgeable
Black-and-white SquareDecide whether the black cells equal the union of some full rows and columns and print the smallest stripe set.	Medium5	MatrixImplementation	No attempts yet	1s	256 MB	Judgeable
King's WalkMove a king n cells over a letter grid to match the motto in as many positions as possible, breaking ties by the smallest coordinate sequence.	Medium5	Dynamic programmingMatrix	No attempts yet	1s	256 MB	Judgeable
Fan migrationAssign every family to a house inside its own supporter block so the total compensation paid to families moving into cheaper houses is minimal.	Medium5	Graph	No attempts yet	1s	256 MB	Judgeable
Hyper-minimumCompute the minimum of every M by M by M by M subcube of a 4D array with up to 1.5 million entries.	Medium5	Sliding windowQueue	No attempts yet	2s	256 MB	Judgeable
Riddick's CubeFind the cheapest column-then-row cyclic shifts that make every row or every column single-colored, or print 100500 when no such shifts exist.	Medium5	Brute forceSimulation+1	No attempts yet	2s	64 MB	Judgeable
Maximal AreaGiven N column heights, find the area of the largest rectangle formed by whole unit squares.	Medium5	StackArray	No attempts yet	2s	256 MB	Judgeable
Perica's PianoSort the N key values and add each value multiplied by the number of K-sets where it is the largest, modulo 1000000007.	Medium5	CombinatoricsSorting+1	No attempts yet	1s	64 MB	Judgeable
The Ant RobotGiven the side lengths of a rectangular box, compute the squared length of the shortest surface path between opposite corners.	Medium5	GeometryMath	No attempts yet	1s	256 MB	Judgeable
DeceptionYou divide the numbers into two nonempty groups with equal XOR to make the first group's sum as large as possible.	Medium5	Bit manipulationGreedy	No attempts yet	1s	256 MB	Judgeable
Preserving the GridPlace d partitions between cells of a 1 by n board holding k horses to maximize cells no horse can reach.	Medium5	GreedySorting	No attempts yet	1s	32 MB	Judgeable
A Strange SequenceYou get the first N terms, each later term equals the count of distinct values before it, and you must output the Mth term.	Medium5	SimulationHash map+1	No attempts yet	1s	64 MB	Judgeable
What a TwistFind the maximum of n times its digitwise nine-complement over all integers from 1 to N for each test case.	Medium5	MathGreedy	No attempts yet	1s	128 MB	Judgeable
ZombiesFind the cheapest route from city 1 to city N, where cities within S roads of a zombie city cost q per night and all other cities cost p.	Medium5	Shortest pathBFS+1	No attempts yet	2s	512 MB	Judgeable
Happy NumbersFind the smallest start of K consecutive integers with exactly L numbers that are at most M or prime, or output -1.	Medium5	Number theoryPrefix sum+1	No attempts yet	0.5s	64 MB	Judgeable
Fruit FeastEat unlimited fruits that add A or B without passing T, using at most one halving, to reach the largest fullness.	Medium5	Dynamic programming	No attempts yet	2s	512 MB	Judgeable
Turning on the lightsBessie walks through lit adjacent rooms to press switches that light new rooms, and every room ever lit counts.	Medium5	BFSGraph	No attempts yet	2s	512 MB	Judgeable
Radio ContactJohn and Bessie each walk or wait along their fixed routes to minimize the summed squared distance until both reach their final points.	Medium5	Dynamic programming	No attempts yet	2s	512 MB	Judgeable
Load BalancingPlace one vertical and one horizontal fence between the odd-coordinate cow positions to minimize the largest cow count in any of the four regions.	Medium5	SortingPrefix sum+1	No attempts yet	2s	512 MB	Judgeable
Circular Barn (Silver)Cows waiting at ring doors walk clockwise to fill each room with one cow at the smallest total squared walking distance.	Medium5	Dynamic programmingBrute force	No attempts yet	2s	512 MB	Judgeable
Load BalancingJohn places one vertical and one horizontal fence to minimize the largest cow count in the four regions.	Medium5	Brute forceSorting	No attempts yet	1s	512 MB	Judgeable
Diamond CollectorSort the diamond sizes and pick two disjoint groups with spread at most K to maximize the total count.	Medium5	SortingTwo pointers	No attempts yet	2s	512 MB	Judgeable
Field ReductionYou remove one of N points to minimize the axis-aligned bounding box area of the rest.	Medium5	Brute forceGeometry	No attempts yet	2s	512 MB	Judgeable
Closing the FarmBarns close one by one in a given order, and the task asks after each step whether all open barns remain connected.	Medium5	Union-findGraph	No attempts yet	2s	512 MB	Judgeable
Cleaning the Club Room!Pick exactly M evenings to reset dirt to zero so the sum of daily visitors times dirt since the last cleaning is smallest.	Medium5	Dynamic programmingPrefix sum	No attempts yet	1s	128 MB	Judgeable
LU decomposition of a band matrixFactor a tridiagonal matrix into unit-diagonal L and upper U, printing -1 when the factors do not exist or a pivot is zero.	Medium5	MatrixMath+1	No attempts yet	3s	128 MB	Judgeable
PairingGiven complete preference rankings of N men and N women, compute the man-optimal stable pairing.	Medium5	GreedySimulation+1	No attempts yet	3s	128 MB	Judgeable
Counting four cyclesCount ordered 4-vertex cycles in an undirected graph given as an N by N adjacency matrix with N up to 250.	Medium5	GraphCombinatorics+1	No attempts yet	2s	128 MB	Judgeable
Mr. Kim's Grocery Store (Small)Given the sorted pile of 2N mixed normal and discounted price tags, recover the N sale prices.	Medium5	GreedyHash map+1	No attempts yet	5s	512 MB	Judgeable
Kim Incheon's Grocery Store (Large)Given 2N sorted tags that pair N sale prices with regular prices at 4/3 of each sale price, recover the N sale tags.	Medium5	GreedyHash map+1	No attempts yet	5s	512 MB	Judgeable
Robot Rock Band (Small)Count quadruples with one element from each of four lists whose bitwise XOR equals K.	Medium5	Hash mapBrute force	No attempts yet	5s	512 MB	Judgeable
Robot Rock Band (Large)Count quadruples with one element from each of four lists whose bitwise XOR equals K.	Medium5	Hash mapBit manipulation	No attempts yet	7s	512 MB	Judgeable
Not So RandomFeed X through N stages that each apply bitwise AND, OR, or XOR with K at given probabilities and report the expected final value.	Medium5	ProbabilityBit manipulation+1	No attempts yet	5s	512 MB	Judgeable
Not So Random (Large)N machines each apply AND, OR, or XOR with K at given probabilities, and the expected output after chaining them must be computed.	Medium5	Bit manipulationProbability+1	No attempts yet	10s	512 MB	Judgeable
Virtual Rabbit (Small)Feed a pet at allowed times of day so no gap between feedings exceeds X seconds, using as few feedings as possible.	Medium5	GreedyIntervals	No attempts yet	5s	512 MB	Judgeable
Total File CountGiven printed pairs of truncated percent and files done, find the unique total file count that fits all lines or report ambiguity.	Medium5	MathIntervals+1	No attempts yet	5s	512 MB	Judgeable
How Many FilesFrom printed percentage and count pairs, recover the unique total file count that fits every truncated percentage, or report that several fit.	Medium5	Math	No attempts yet	5s	512 MB	Judgeable
Elf Tournament BracketDecide if up to 8 elves can be ordered so no sensitive elf meets a listed friend within its first K rounds under any match outcomes.	Medium5	Brute forceImplementation	No attempts yet	5s	512 MB	Judgeable
Sum of submatrix maximaAdd up the maximum value inside every K by K submatrix of an N by N matrix generated from two arrays.	Medium5	Sliding windowMatrix+1	No attempts yet	20s	1024 MB	Judgeable
Googol String (Large)Answer the Kth character of a recursively defined binary string for each query with K up to 10^18.	Medium5	RecursionBit manipulation	No attempts yet	5s	512 MB	Judgeable
gCube (Large)Answer many range queries asking for the geometric mean of array values with nine digits after the decimal point.	Medium5	Prefix sumMath	No attempts yet	5s	512 MB	Judgeable
gCampus (Large)Find every road that never appears on a shortest travel-time path between any pair of offices.	Medium5	Shortest pathGraph	No attempts yet	5s	512 MB	Judgeable
2048 (Hard)Slide and merge tiles on an N by N board for at most ten moves to maximize the largest tile.	Medium5	Brute forceBacktracking+1	No attempts yet	1s	512 MB	Judgeable
Lunch MenuCount the menus whose spiciness falls in [u, v] and whose sweetness falls in [x, y] for each query.	Medium5	Segment treeSorting+1	No attempts yet	1s	512 MB	Judgeable
2048 (Easy)Find the largest tile reachable within at most five 2048 moves on a given board where no new tiles appear.	Medium5	Brute forceBacktracking+1	No attempts yet	1s	512 MB	Judgeable
TournamentWith free seeding of 2^N numbers in a knockout bracket, find the best level each number can reach.	Medium5	SortingMath	No attempts yet	3s	64 MB	Judgeable
Fairland (Small)Marie keeps the largest manager-closed team containing herself whose salaries span at most D.	Medium5	TreeDFS+2	No attempts yet	5s	512 MB	Judgeable
PegmanFind the fewest arrow direction changes so a walker starting from any cell never leaves the grid, or report that it is impossible.	Medium5	GreedySimulation	No attempts yet	5s	512 MB	Judgeable
Typewriter Monkey (Small)Find the expected leftover bananas, which is the maximum achievable count of the target word minus its expected count in a random length S string.	Medium5	ProbabilityBrute force+1	No attempts yet	5s	512 MB	Judgeable
Typewriter MonkeyFrom keyboard letter frequencies, subtract the expected overlapping occurrences of a target word in a random length-S string from the maximum possible count.	Medium5	ProbabilityString matching	No attempts yet	5s	512 MB	Judgeable
Counter Culture (Small)Count from 1 to N where each step adds 1 or reverses the digits, and find the fewest spoken numbers.	Medium5	BFSGraph	No attempts yet	5s	512 MB	Judgeable
Haircut QueueFind which of B barbers with fixed cutting times serves the Nth customer when each free barber takes the next waiting customer.	Medium5	Binary searchMath	No attempts yet	5s	512 MB	Judgeable