Problems

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Total results29,478 problems

Politics
Easy3
Sorting, Hash map
No attempts yet
Time limit
15s
Memory limit
256 MB
Judgeable
Generations of Tribbles
Easy3
Dynamic programming
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Languages
Easy3
Hash map, String
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Football
Easy3
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
What does the fox say?
Easy3
Hash map, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bus 3000
Easy3
Math, Recursion
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Between the Mountains
Easy3
Two pointers, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Goldilocks and the N Cows
Easy3
Sorting, Intervals
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Lucky Numbers
Easy3
Brute force, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Equal Sum Sets
Easy3
Dynamic programming, Combinatorics
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Maximum Word Frequency
Easy3
Hash map, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
GCD Sum
Easy3
Number theory, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Meeting Room Arrangement
Easy3
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
BABBA
Easy3
Dynamic programming, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Self-descriptive sentence
Easy3
Brute force, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Grachten
Easy3
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stone Game
Easy3
Dynamic programming, Game theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stone Game 2
Easy3
Game theory, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stone Game 3
Easy3
Dynamic programming, Game theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stone Game 4
Easy3
Dynamic programming, Game theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stone Game 6
Easy3
Game theory, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Original Number of Medallions
Easy3
Math, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Picking a device for the movie
Easy3
Simulation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sifar
Easy3
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Who you know
Easy3
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Filter and Perform
Easy3
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Sultan's Chapati
Easy3
Simulation, Array+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rainforest Canopy
Easy3
DFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Charles Babbage's Difference Engine
Easy3
Simulation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Surface Area
Easy3
Simulation, Matrix
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bi-coloring
Easy3
BFS, Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Perfect Cube
Easy3
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Negative Binary
Easy3
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mini Sudoku X
Easy3
Implementation, Matrix
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Pair Sum
Easy3
Two pointers, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dihedral Group Product
Easy3
Math, Implementation
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Sharkovski's Ordering
Easy3
Sorting, Math
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Permutation
Easy3
Combinatorics, Math
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Product of two distinct primes
Easy3
Number theory, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Candy Factory
Easy3
Tree, Recursion+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Village closeness
Easy3
Brute force, Geometry
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Six Equations
Easy3
Number theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Straight Flush
Easy3
Sorting, Hash map
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Largest Pairwise GCD
Easy3
Brute force, Number theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Unlock My Safe
Easy3
Combinatorics, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Two Mysterious Alphabets from a Tree
Easy3
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Range Sum Query
Easy3
Prefix sum, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Knight Moves
Easy3
BFS, Matrix
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Boiled Eggs
Easy3
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Damage Over Time
Easy3
Sorting, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Common Fraction
Easy3
Number theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Olympic Games Ranking
Easy3
Sorting, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Elephant Show
Easy3
DFS, Matrix
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Another Word Sorting
Easy3
Sorting, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cracking Tree Codes
Easy3
Simulation, Tree+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cabric Number
Easy3
Simulation, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Quantity of White Mice
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Color Change of Go Stones
Easy3
Simulation, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Selecting the Ten Best Teachers
Easy3
Simulation, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Paint
Easy3
Greedy, Sorting
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Best Machine Rental Profit
Easy3
Dynamic programming, Array
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
The nth prime number
Easy3
Number theory, Math
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
LVM
Easy3
Simulation, Stack
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Gecko
Easy3
Dynamic programming, Matrix
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Playing Fair with Cryptography
Easy3
Simulation, Implementation+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Calling All Programmers
Easy3
Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rocky
Easy3
Simulation, Matrix
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Record Keeping
Easy3
Hash map, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Ski Course Design
Easy3
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
E-Casino
Easy3
String matching, Brute force
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Quadtree Image Compression
Easy3
Divide and conquer, Recursion+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Mystery Graph Coloring
Easy3
Graph, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Complete Binary Tree
Easy3
Tree, Recursion
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bree's pantry
Easy3
Sorting, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Paula's dress search
Easy3
Simulation, Binary search
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Recycling Bin Allocation
Easy3
Brute force, Combinatorics
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Reversing Words
Easy3
String, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Word Crosses
Easy3
String, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Byte Me!
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
World's Worst Bus Schedule
Easy3
Simulation, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Does This Make Me Look Fat?
Easy3
Sorting, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Frogger's For Dinner
Easy3
Simulation, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Asteroids!
Easy3
BFS, Matrix
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
When I miss Korea, I log in to the server
Easy3
String matching, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Reordering the Cows
Easy3
Array, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Color Weakness
Easy3
BFS, Matrix
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Three Friends
Easy3
String, Brute force
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
The Geneva Confection
Easy3
Stack
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
One Number Hint
Easy3
Combinatorics, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Seat Assignment
Easy3
Simulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Ant
Easy3
Math
No attempts yet
Time limit
0.15s
Memory limit
256 MB
Judgeable
Balance Scale
Easy3
Graph, DFS
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Colored Paper
Easy3
Simulation, Matrix+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Grid Path Count
Easy3
Combinatorics, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Opposite Words
Easy3
Hash map, String
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Federation Favorites
Easy3
Number theory, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Snake game simulation
Easy3
Simulation, Queue
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Coupon Discount 2
Easy3
Hash map, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Underwater Trip
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Minion Walk
Easy3
BFS, Matrix+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
PoliticsOrder supporters by the listed candidate order, keep original order within each candidate, and group unlisted candidates at the end by first appearance.	Easy3	SortingHash map	No attempts yet	15s	256 MB	Judgeable
Generations of TribblesCompute the nth term of a four-term Fibonacci-like recurrence for up to 68 test cases with precomputation.	Easy3	Dynamic programming	No attempts yet	2s	128 MB	Judgeable
LanguagesEach sample line is assigned to the language whose keywords it contains, matched case-insensitively after splitting on spaces and punctuation.	Easy3	Hash mapString	No attempts yet	3s	128 MB	Judgeable
FootballDistribute at most G bought goals across N finished matches to maximize total points, with 3 for a win and 1 for a draw.	Easy3	GreedySorting	No attempts yet	1s	128 MB	Judgeable
What does the fox say?Remove every known animal sound from the recording and print the remaining words in order as the fox sounds.	Easy3	Hash mapString	No attempts yet	1s	128 MB	Judgeable
Bus 3000Given k stops where half the riders plus half a rider get off each time until the bus is empty, find the starting passenger count.	Easy3	MathRecursion	No attempts yet	1s	128 MB	Judgeable
Between the MountainsPick one altitude from each mountain so the absolute difference between the two is as small as possible.	Easy3	Two pointersSorting	No attempts yet	1s	128 MB	Judgeable
Goldilocks and the N CowsChoose an integer barn temperature that maximizes total milk when each cow yields X if cold, Y if inside its range, and Z if hot.	Easy3	SortingIntervals	No attempts yet	1s	128 MB	Judgeable
Lucky NumbersCount distinct sums of one element from each of three arrays whose decimal digits are only 5 and 8.	Easy3	Brute forceHash map+1	No attempts yet	1s	128 MB	Judgeable
Equal Sum SetsCount subsets of {1..n} with exactly k elements that sum to s for each dataset.	Easy3	Dynamic programmingCombinatorics	No attempts yet	3s	128 MB	Judgeable
Maximum Word FrequencyCount n lowercase words and print the most frequent word and its count, breaking ties by last lexicographical order.	Easy3	Hash mapString	No attempts yet	1s	128 MB	Judgeable
GCD SumGiven several integers per test case, add the greatest common divisor of every unordered pair and print each sum.	Easy3	Number theoryBrute force	No attempts yet	1s	128 MB	Judgeable
Meeting Room ArrangementPick the largest set of non-overlapping events in each test case from given start and finish times.	Easy3	GreedySorting	No attempts yet	1s	128 MB	Judgeable
BABBAStarting from A and rewriting each B as BA and each A as B, count the As and Bs after K presses.	Easy3	Dynamic programmingMath	No attempts yet	1s	128 MB	Judgeable
Self-descriptive sentenceFill the blank in the sentence with the smallest number below 1000 whose glued English spelling makes the total letter count equal that number.	Easy3	Brute forceString+1	No attempts yet	1s	128 MB	Judgeable
GrachtenThree paced distances along two sight lines fix similar triangles that yield the canal width as a reduced fraction.	Easy3	GeometryMath	No attempts yet	1s	128 MB	Judgeable
Stone GameTwo players alternately take 1 or 3 stones from a pile of N, and the program names the winner under perfect play.	Easy3	Dynamic programmingGame theory	No attempts yet	1s	128 MB	Judgeable
Stone Game 2Two players alternately take 1 or 3 stones from a pile of N and the player taking the last stone loses, so print whether the first player wins.	Easy3	Game theoryDynamic programming	No attempts yet	1s	128 MB	Judgeable
Stone Game 3Two players alternately take 1, 3, or 4 stones from a pile of N, and the program reports whether the first player wins with perfect play.	Easy3	Dynamic programmingGame theory	No attempts yet	1s	128 MB	Judgeable
Stone Game 4Two players alternately take 1, 3, or 4 stones and the player taking the last stone loses; report whether the first player wins with optimal play.	Easy3	Dynamic programmingGame theory	No attempts yet	1s	128 MB	Judgeable
Stone Game 6Two players alternately take 1, 3, or 4 stones from a pile of N, and the program prints which player wins with perfect play.	Easy3	Game theoryDynamic programming	No attempts yet	1s	128 MB	Judgeable
The Original Number of MedallionsGiven the daughter count and the medallions left after the youngest keeps one smallest split share, find the smallest and largest possible original counts.	Easy3	MathBrute force	No attempts yet	1s	128 MB	Judgeable
Picking a device for the movieGiven a movie resolution, pick the cheapest of eight listed devices that maximizes the full-screen usage ratio in either orientation.	Easy3	SimulationMath+1	No attempts yet	1s	128 MB	Judgeable
SifarFor each N up to 1,000,000 given one per line until 0, print the count of trailing zeros of N! as Case #x: M.	Easy3	Number theoryMath	No attempts yet	1s	128 MB	Judgeable
Who you knowFind the cheapest chain of introductions from politician 0 to politician M-1 in an undirected graph with edge weights 1 to 4, printing -1 when unreachable.	Easy3	Shortest pathGraph	No attempts yet	1s	128 MB	Judgeable
Filter and PerformClassify each token as integer, real, or string and apply the matching digit-sum, deletion, or exponential-format operation per case.	Easy3	StringImplementation	No attempts yet	1s	128 MB	Judgeable
The Sultan's ChapatiFollow the prescribed flip procedure to sort each stack largest on the bottom and print the flip positions ending with 0.	Easy3	SimulationArray+1	No attempts yet	1s	128 MB	Judgeable
Rainforest CanopyCount the groups of 1s connected through all eight neighbours in each square binary image.	Easy3	DFSGraph+1	No attempts yet	1s	128 MB	Judgeable
Charles Babbage's Difference EngineGiven the first values of a low-degree polynomial, extend its finite-difference table forward and report the value at x = 50.	Easy3	SimulationMath+1	No attempts yet	1s	128 MB	Judgeable
Surface AreaGiven column heights on a grid, compute the total exposed surface area of the solid, including top, sides, and floor.	Easy3	SimulationMatrix	No attempts yet	1s	128 MB	Judgeable
Bi-coloringCount the two-colorings where every edge joins different colors, or report -1 when the graph is not bipartite.	Easy3	BFSGraph	No attempts yet	1s	128 MB	Judgeable
Perfect CubeCount the integers between A and B, inclusive, that are perfect cubes for each of up to 100000 test cases.	Easy3	Math	No attempts yet	1s	128 MB	Judgeable
Negative BinaryConvert each given decimal integer to its base negative two representation without leading zeros.	Easy3	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Mini Sudoku XRead 6 by 6 grids and report whether each row, column, diagonal, and 2 by 3 block holds digits 1 to 6 exactly once.	Easy3	ImplementationMatrix	No attempts yet	1s	256 MB	Judgeable
Pair SumCount pairs in a sorted distinct array that sum to a target M for each test case.	Easy3	Two pointersArray	No attempts yet	1s	128 MB	Judgeable
Dihedral Group ProductMultiply two given elements of D_{m,n} with the relation ba = a^{m-1}b and print each product with exponents reduced modulo m and n.	Easy3	MathImplementation	No attempts yet	5s	128 MB	Judgeable
Sharkovski's OrderingSort each test case of up to 255 integers into Sharkovski ordering and print them space-separated on one line.	Easy3	SortingMath	No attempts yet	2s	128 MB	Judgeable
PermutationGiven up to 10 distinct sorted characters and a 1-based position, print the permutation at that position or No permutation when it exceeds n!.	Easy3	CombinatoricsMath	No attempts yet	5s	128 MB	Judgeable
Product of two distinct primesFor each K, print the smallest number at or above K that equals the product of two different primes.	Easy3	Number theoryBrute force	No attempts yet	1s	128 MB	Judgeable
Candy FactoryEach parent in a heap-ordered binary tree makes as many candies as the smaller child count, and the total subtracts consumed ingredients from all made candies.	Easy3	TreeRecursion+1	No attempts yet	1s	128 MB	Judgeable
Village closenessGiven N points in 3D, find the smallest sum of Manhattan distances from one point to two other distinct points.	Easy3	Brute forceGeometry	No attempts yet	1s	128 MB	Judgeable
Six EquationsRecover six bounded primes from six pairwise products by taking gcds of the pairs that share a prime.	Easy3	Number theory	No attempts yet	1s	128 MB	Judgeable
Straight FlushFind the longest run of consecutive ranks sharing one suit after merging duplicate cards.	Easy3	SortingHash map	No attempts yet	5s	512 MB	Judgeable
Largest Pairwise GCDGiven up to 100 positive integers below one million, find the largest GCD over all pairs from distinct positions.	Easy3	Brute forceNumber theory	No attempts yet	1s	128 MB	Judgeable
Unlock My SafeThe program prints the sorted permutation of digits 1 to N at index floor(N factorial / 3) for each N.	Easy3	CombinatoricsSorting+1	No attempts yet	1s	128 MB	Judgeable
Two Mysterious Alphabets from a TreeFind the max-sum root-to-leaf path in a number triangle, breaking ties by larger sum of squares, then print both sums and their mod-26 letters.	Easy3	Dynamic programming	No attempts yet	1s	128 MB	Judgeable
Range Sum QueryAnswer many inclusive range sum queries on a static integer list using precomputed prefix sums.	Easy3	Prefix sumArray	No attempts yet	1s	128 MB	Judgeable
Knight MovesFind the fewest knight moves from K to X on a grid with blocked squares, or output -1 when unreachable.	Easy3	BFSMatrix	No attempts yet	1s	128 MB	Judgeable
Boiled EggsSort the eggs by weight and boil the lightest ones while the count stays within P and the total weight stays within Q.	Easy3	GreedySorting	No attempts yet	1s	128 MB	Judgeable
Damage Over TimePick up to M abilities to maximize total damage per second, breaking ties by longest shared duration, and report both numbers.	Easy3	SortingGreedy	No attempts yet	1s	128 MB	Judgeable
Common FractionReduce each of n fractions to lowest terms by dividing out the greatest common divisor.	Easy3	Number theory	No attempts yet	1s	128 MB	Judgeable
Olympic Games RankingSort up to 250 nations by gold, silver, then bronze medals and print competition ranks with totals, breaking ties alphabetically.	Easy3	SortingImplementation	No attempts yet	1s	128 MB	Judgeable
Elephant ShowCount the yellow tiles reachable from the elephant start by moving up, down, left, or right.	Easy3	DFSMatrix	No attempts yet	1s	128 MB	Judgeable
Another Word SortingSort up to 1000 lowercase words by letter-value totals plus a bonus for each adjacent equal pair, breaking ties alphabetically.	Easy3	SortingString	No attempts yet	1s	128 MB	Judgeable
Cracking Tree CodesGiven a tree and its leaf-stripping code with some entries erased, the program replays the encoding to recover the missing numbers.	Easy3	SimulationTree+1	No attempts yet	1s	128 MB	Judgeable
Cabric NumberSimulate the Kaprekar digit routine to 6174 or 0 for each input and print every subtraction step.	Easy3	SimulationSorting	No attempts yet	1s	128 MB	Judgeable
Quantity of White MiceSimulate monthly mouse pairs with age-based births, death after month n, and newborn removal past 100 survivors to find the month k count.	Easy3	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Color Change of Go StonesRepeat k times the rule that replaces each circular gap with the xor of its two neighbors, then count the white stones.	Easy3	SimulationArray	No attempts yet	1s	128 MB	Judgeable
Selecting the Ten Best TeachersTally valid ballots into weighted place scores and print the top ten teachers with vote breakdowns in fixed-width columns.	Easy3	SimulationSorting+1	No attempts yet	1s	128 MB	Judgeable
PaintDo n paint jobs one per day, highest daily price rise first, to minimize base prices plus accumulated surcharges.	Easy3	GreedySorting	No attempts yet	2s	512 MB	Judgeable
Best Machine Rental ProfitEach record maps letters to profits, and the task asks for the largest sum over any contiguous block, or zero when every block loses money.	Easy3	Dynamic programmingArray	No attempts yet	2s	512 MB	Judgeable
The nth prime numberGiven n up to 10000, print the nth prime number.	Easy3	Number theoryMath	No attempts yet	2s	512 MB	Judgeable
LVMSimulate the stack machine program and print the value shown by the first DONE instruction.	Easy3	SimulationStack	No attempts yet	2s	512 MB	Judgeable
GeckoPick a top-row tile and move straight down, down-left, or down-right each row to maximize the mosquitoes eaten.	Easy3	Dynamic programmingMatrix	No attempts yet	2s	512 MB	Judgeable
Playing Fair with CryptographyGiven a key and a plaintext, build the 5x5 Playfair grid and encrypt the text into digraphs with cycling filler letters.	Easy3	SimulationImplementation+2	No attempts yet	2s	128 MB	Judgeable
Calling All ProgrammersCount around n callers in a circle with step m and report the position of the k-th caller removed.	Easy3	Simulation	No attempts yet	1s	128 MB	Judgeable
RockyA horse walks straight across a grid and turns by fixed rules when a rock blocks it; report the exit square and the number of stepped squares.	Easy3	SimulationMatrix	No attempts yet	1s	128 MB	Judgeable
Record KeepingCount how many times the most repeated unordered group of three cow names appears in N lines.	Easy3	Hash mapSorting	No attempts yet	1s	128 MB	Judgeable
Ski Course DesignJohn moves each hill by an integer amount at squared cost so all heights fit in an interval of length 17 for the minimum total.	Easy3	Brute forceMath	No attempts yet	1s	128 MB	Judgeable
E-CasinoFind the smallest shift k where the observed bits match the public array up to a repeating mask.	Easy3	String matchingBrute force	No attempts yet	2s	512 MB	Judgeable
Quadtree Image CompressionCount the bits produced by recursively splitting an L by L binary image into quadrants until each block is uniform.	Easy3	Divide and conquerRecursion+1	No attempts yet	2s	1024 MB	Judgeable
Mystery Graph ColoringColor vertices 0 to V-1 with the smallest color unused by colored neighbors, then print the color count, the colors, and the loop counter.	Easy3	GraphGreedy+1	No attempts yet	1s	128 MB	Judgeable
Complete Binary TreeReconstruct each level of a complete binary tree from its inorder visit order.	Easy3	TreeRecursion	No attempts yet	1s	128 MB	Judgeable
Bree's pantrySort the cans by height with a case-insensitive code tiebreak, then place them alternately left and right from the middle and print the row.	Easy3	SortingSimulation	No attempts yet	1s	128 MB	Judgeable
Paula's dress searchCount how many middle-shop visits Paula needs to reach the shop holding her dress.	Easy3	SimulationBinary search	No attempts yet	1s	128 MB	Judgeable
Recycling Bin AllocationFind the waste-to-bin assignment that needs the fewest bin changes across all surveyed cities.	Easy3	Brute forceCombinatorics	No attempts yet	1s	128 MB	Judgeable
Reversing WordsReverse the letters of each word on every input line while keeping punctuation, spaces, and the capital pattern in place.	Easy3	StringSimulation	No attempts yet	1s	128 MB	Judgeable
Word CrossesFor each set of four words, print both leading word crosses side by side on one shared row.	Easy3	StringSimulation	No attempts yet	1s	128 MB	Judgeable
Byte Me!Simulate the dealer's fixed hitting rules in binary blackjack and report each hit and whether the dealer wins, busts, or loses.	Easy3	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
World's Worst Bus ScheduleGiven each bus's repeating route durations and your arrival time, compute how long you wait for the next bus to reach the station.	Easy3	SimulationMath	No attempts yet	1s	128 MB	Judgeable
Does This Make Me Look Fat?Sort each group of dieters by current weight, computed as starting weight minus days on the diet, heaviest first.	Easy3	SortingImplementation	No attempts yet	1s	128 MB	Judgeable
Frogger's For DinnerSimulate a frog walking down a 10 by 10 road while cars wrap around their lanes and decide if any starting column reaches the far side alive.	Easy3	SimulationBrute force+1	No attempts yet	1s	128 MB	Judgeable
Asteroids!Find the shortest 6-directional path through an N by N by N grid with blocked cells, or report that no route exists.	Easy3	BFSMatrix	No attempts yet	1s	128 MB	Judgeable
When I miss Korea, I log in to the serverDecide for each of up to 100 file names whether it starts with the pattern prefix and ends with the pattern suffix around the single asterisk.	Easy3	String matchingString	No attempts yet	1s	128 MB	Judgeable
Reordering the CowsGiven the current and target cow orders, count the permutation cycles longer than one and report the longest cycle length.	Easy3	ArraySimulation	No attempts yet	1s	128 MB	Judgeable
Color WeaknessCount connected R, G, B regions in an N by N grid twice, once normally and once with R and G merged.	Easy3	BFSMatrix	No attempts yet	1s	128 MB	Judgeable
Three FriendsGiven U, find the string S such that deleting one character from U yields S repeated twice, or report NOT POSSIBLE or NOT UNIQUE.	Easy3	StringBrute force	No attempts yet	1s	256 MB	Judgeable
The Geneva ConfectionDecide if cars arriving top to bottom can be released in order 1 to N using a side branch as a stack.	Easy3	Stack	No attempts yet	1s	256 MB	Judgeable
One Number HintImplement two fixed rules over 6-element subsets of 1 to 12: output the smallest element in S(x) missing from S(y), and answer yes when h lies in S(q).	Easy3	CombinatoricsImplementation	No attempts yet	1s	256 MB	Judgeable
Seat AssignmentFind the (x, y) seat of the K-th person placed in a clockwise inward spiral from the bottom-left corner of a C by R grid, or print 0 when K exceeds capacity.	Easy3	Simulation	No attempts yet	1s	256 MB	Judgeable
AntCompute the position of an ant moving diagonally and reflecting off the walls of a w by h box after t hours.	Easy3	Math	No attempts yet	0.15s	256 MB	Judgeable
Balance ScaleGiven pairwise heavier-than results, count for each object how many others have no implied comparison.	Easy3	GraphDFS	No attempts yet	1s	256 MB	Judgeable
Colored PaperCompute the area of each of N overlapping axis-aligned rectangles that stays visible after later rectangles cover it.	Easy3	SimulationMatrix+1	No attempts yet	1s	64 MB	Judgeable
Grid Path CountCount right-and-down paths from the top-left to the bottom-right corner that pass through a given cell, if one is specified.	Easy3	CombinatoricsDynamic programming	No attempts yet	1s	256 MB	Judgeable
Opposite WordsDecide for each word whether every letter appears as often as its opposite letter from the other end of the alphabet, ignoring case and non-letters.	Easy3	Hash mapString	No attempts yet	1s	256 MB	Judgeable
Federation FavoritesRead integers until -1 and print each perfect number with its divisors or state that it is not perfect.	Easy3	Number theoryImplementation	No attempts yet	1s	256 MB	Judgeable
Snake game simulationSimulate 20 snake moves on a 15 by 15 board with growth on pellets and print the pellet count or game over with the final board.	Easy3	SimulationQueue	No attempts yet	1s	256 MB	Judgeable
Coupon Discount 2Apply each matching coupon discount to the purchased UPC prices and list coupons with no matching purchase as invalid.	Easy3	Hash mapImplementation	No attempts yet	1s	256 MB	Judgeable
Underwater TripSimulate each steering sequence through the tunnel and report whether it reaches the end or crashes into the ceiling, floor, or a stalagmite.	Easy3	SimulationImplementation	No attempts yet	1s	256 MB	Judgeable
Minion WalkMark every grid cell reachable from the top-left corner, print the room as an ASCII table, and report whether the bottom-right cell is reachable.	Easy3	BFSMatrix+1	No attempts yet	1s	256 MB	Judgeable