Problems

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Total results29,476 problems

Set
Easy3
Bit manipulation, Implementation
No attempts yet
Time limit
1.5s
Memory limit
4 MB
Judgeable
Number of connected components
Easy3
Graph, DFS
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Finding Parents in a Tree
Easy3
BFS, Tree
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
2 by n Tiling
Easy3
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
2 by n Tiling 2
Easy3
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Merging Two Sorted Arrays
Easy3
Two pointers, Array
No attempts yet
Time limit
1.5s
Memory limit
256 MB
Judgeable
Tower of Hanoi move sequence
Easy3
Recursion, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Settlement Office
Easy3
Hash map, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Mastering Mastermind
Easy3
Array, String
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Shuffling Along
Easy3
Simulation, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Squawk Virus
Easy3
Dynamic programming, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
What's on the Grille?
Easy3
Simulation, Matrix
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Orienting Molecular Bonds
Easy3
BFS, Tree
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Programming Contest Strategy
Easy3
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Even? Odd?
Easy3
Number theory, Math
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Document signatures
Easy3
Greedy, Simulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Collider
Easy3
Array, Simulation
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Josephus Permutation
Easy3
Queue, Simulation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Padding a bracket string
Easy3
Stack, Greedy
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Array Escape
Easy3
Dynamic programming, Shortest path+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Preparing a knapsack problem
Easy3
Combinatorics, Implementation
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Forest Fruits
Easy3
Simulation, Brute force
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Sorting Numbers 4
Easy3
Sorting
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
ACM-ICPC Scoreboard
Easy3
Simulation, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Russian Flag
Easy3
Brute force, Prefix sum
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Pretty printing arrays
Easy3
Stack, Simulation
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Fly Swatter
Easy3
Prefix sum, Matrix+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Resistor Circuit
Easy3
Stack, Math
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Breed Counting
Easy3
Prefix sum, Array
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Contaminated Milk
Easy3
Simulation, Brute force
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Angry Cows (Bronze)
Easy3
Simulation, Sorting
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Mowing the Field
Easy3
Simulation, Hash map
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Balanced Fence Partition
Easy3
Brute force, Sorting
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Diamond Collector (Bronze)
Easy3
Sorting, Sliding window
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Bull in a China Shop (Bronze)
Easy3
Brute force, Simulation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Younghoon the Prankster
Easy3
Combinatorics, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Polynesiaglot (Small 1)
Easy3
Dynamic programming, Combinatorics
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Polynesiaglot
Easy3
Dynamic programming, Combinatorics
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Polynesiaglot (Large)
Easy3
Dynamic programming, Combinatorics
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Lazy Spelling Bee (Small)
Easy3
Combinatorics, String
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Dynamic Grid (Small)
Easy3
BFS, Graph+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
gRanks (Small)
Easy3
Sorting, Hash map+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
gRanks
Easy3
Sorting, Hash map+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Googol String (Small)
Easy3
Recursion, Simulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Bad Horse (Small 1)
Easy3
Graph, BFS
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Bad Horse (Small2)
Easy3
Graph, BFS
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Captain Hammer (Small)
Easy3
Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Sums of 1, 2, 3 (2)
Easy3
Backtracking, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
H-Index
Easy3
Sorting
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Crane Truck (Small)
Easy3
Simulation, Implementation
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Mushroom Monster (Small)
Easy3
Simulation, Greedy
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Standing Ovation (Small)
Easy3
Greedy
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Standing Ovation (Large)
Easy3
Greedy
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Sort a scrambled itinerary (Small)
Easy3
Hash map, Graph
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Sort a scrambled itinerary (Large)
Easy3
Hash map
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
One move captures (small)
Easy3
Simulation, Brute force
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Captures in One Move
Easy3
Simulation, Implementation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Super 2048 (Small)
Easy3
Simulation, Matrix
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Super 2048 (Large)
Easy3
Simulation, Matrix
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Sudoku Solution Checker
Easy3
Matrix, Hash map
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Sudoku Solution Checker
Easy3
Matrix, Hash map+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Meet and party (small)
Easy3
Brute force
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Read Phone Number (Large)
Easy3
Implementation, String
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Bookshelf Sorting
Easy3
Sorting, Array
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Sorting the Bookshelf
Easy3
Sorting, Array
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Cross the maze (Small)
Easy3
Simulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Cross the maze (large)
Easy3
Simulation, Matrix
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Consonants (Small)
Easy3
String, Two pointers
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Hedgemony (Large)
Easy3
Simulation, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Ocean View (Small)
Easy3
Brute force, Array
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Aerobics Mat Placement
Easy3
Simulation, Greedy
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Aerobics (Large)
Easy3
Simulation, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Password Retyping
Easy3
Probability, Math+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Speaking in Tongues (Small)
Easy3
Hash map, String
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Commute War (Small)
Easy3
Probability, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
New Calendar (Small)
Easy3
Simulation, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Equation restoration (Small)
Easy3
Brute force, String+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Snapper Chain (Small)
Easy3
Bit manipulation, Simulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Theme Park (Small)
Easy3
Simulation, Queue
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Perpetual Motion (Small)
Easy3
Brute force, Simulation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Mystery Square (Small)
Easy3
Brute force, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Square Tiles
Easy3
Greedy, Matrix+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Square Tiles (Large)
Easy3
Greedy, Matrix+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Perfect Harmony (Small)
Easy3
Number theory, Brute force
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Ratings Percentage Index
Easy3
Simulation, Math+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
RPI (Large)
Easy3
Simulation, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Button-Pressing Robots
Easy3
Simulation, Greedy
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Two Button-Pressing Robots
Easy3
Simulation, Greedy
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Magicka (Small)
Easy3
Simulation, Stack
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Magicka Element Combining
Easy3
Simulation, Stack
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Twibet (Small)
Easy3
Graph, DFS
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Building a House (Large)
Easy3
Brute force, Prefix sum+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Grazing Goats (Small)
Easy3
Geometry, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Rope Intranet
Easy3
Sorting, Brute force
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Rope Intranet
Easy3
Sorting, Brute force
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
File Fix-it (Small)
Easy3
Trie, String
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
File Fix-it (Large)
Easy3
Trie, String
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Rotate the Board
Easy3
Simulation, Matrix+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Board Rotation
Easy3
Simulation, Matrix+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Theme Park (Small)
Easy3
Simulation, Queue
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
SetMaintain a set of integers 1 to 20 under add, remove, toggle, check, all, and empty, and print each check result.	Easy3	Bit manipulationImplementation	No attempts yet	1.5s	4 MB	Judgeable
Number of connected componentsCount the connected components of an undirected graph given its vertices and edges.	Easy3	GraphDFS	No attempts yet	3s	512 MB	Judgeable
Finding Parents in a TreeStarting from node 1 as the root, print the parent of every other node in the given tree.	Easy3	BFSTree	No attempts yet	1s	256 MB	Judgeable
2 by n TilingCount the ways to tile a 2 by n rectangle with 1 by 2 dominoes and print the count modulo 10007.	Easy3	Dynamic programming	No attempts yet	1s	256 MB	Judgeable
2 by n Tiling 2Count the ways to tile a 2 by n rectangle with dominoes and 2 by 2 squares, modulo 10007.	Easy3	Dynamic programming	No attempts yet	1s	256 MB	Judgeable
Merging Two Sorted ArraysMerge two sorted arrays into one sorted sequence with a two-pointer walk.	Easy3	Two pointersArray	No attempts yet	1.5s	256 MB	Judgeable
Tower of Hanoi move sequencePrint the minimal sequence of moves that transfers N disks from rod 1 to rod 3 under the smaller-on-larger rule.	Easy3	RecursionImplementation	No attempts yet	1s	256 MB	Judgeable
Settlement OfficeReport each row or column sum in a grid holding x plus y, zeroing that row or column after each query.	Easy3	Hash mapMath	No attempts yet	1s	256 MB	Judgeable
Mastering MastermindGiven a secret code and a guess of colored pegs, count exact position matches and remaining color-only matches.	Easy3	ArrayString	No attempts yet	1s	256 MB	Judgeable
Shuffling AlongGiven a deck size and shuffle type, count how many repeated perfect shuffles restore the original order.	Easy3	SimulationMath	No attempts yet	1s	256 MB	Judgeable
Squawk VirusStarting from user s, propagate squawk counts along links for t minutes and report how many squawks are sent at time t.	Easy3	Dynamic programmingGraph	No attempts yet	1s	256 MB	Judgeable
What's on the Grille?Recover the original grid message from the encrypted letters by rotating the grille, or report that the grille is invalid.	Easy3	SimulationMatrix	No attempts yet	1s	256 MB	Judgeable
Orienting Molecular BondsDirect every tree edge from the endpoint at even distance from node 1 to the one at odd distance.	Easy3	BFSTree	No attempts yet	1s	64 MB	Judgeable
Programming Contest StrategyPick and order contest problems to solve the most within the time limit with the smallest total penalty time.	Easy3	GreedySorting	No attempts yet	1s	256 MB	Judgeable
Even? Odd?Decide for each of up to 100 numbers up to 1e18 whether its divisor count is odd or even.	Easy3	Number theoryMath	No attempts yet	2s	256 MB	Judgeable
Document signaturesSchedule N officials in fixed order on their accepted weekdays to minimize the total days from the first Monday.	Easy3	GreedySimulation	No attempts yet	1s	256 MB	Judgeable
ColliderMove the particle at position i to position j on each exposure and report the particle type at position k for each query.	Easy3	ArraySimulation	No attempts yet	2s	256 MB	Judgeable
Josephus PermutationRemove every Kth person from a circle of N people and print the removal order in angle brackets.	Easy3	QueueSimulation	No attempts yet	2s	512 MB	Judgeable
Padding a bracket stringAdd the fewest opening brackets at the front and closing brackets at the back to turn the given parenthesis string into a correct bracket sequence.	Easy3	StackGreedy	No attempts yet	1s	32 MB	Judgeable
Array EscapeFind the cheapest right-and-down path through a square grid where stepping to a higher or equal neighbor costs the raises needed to exceed it.	Easy3	Dynamic programmingShortest path+1	No attempts yet	2s	256 MB	Judgeable
Preparing a knapsack problemRead t up to 1e18 and print k = 300 with sixty 1s plus extra elements chosen by greedy binomial decomposition so exactly t subsets sum to 300.	Easy3	CombinatoricsImplementation	No attempts yet	1s	32 MB	Judgeable
Forest FruitsChoose a starting fruit, then walk forward eating each fruit that still fits within capacity C, and report the largest count.	Easy3	SimulationBrute force	No attempts yet	1s	64 MB	Judgeable
Sorting Numbers 4Sort N distinct integers in descending order and print one per line.	Easy3	Sorting	No attempts yet	2s	256 MB	Judgeable
ACM-ICPC ScoreboardReplay the judging log to count each team's solved problems and penalty time, then print all teams in rank order.	Easy3	SimulationSorting	No attempts yet	1s	128 MB	Judgeable
Russian FlagChoose the two row boundaries for the white, blue, and red bands so the number of repainted cells is smallest.	Easy3	Brute forcePrefix sum	No attempts yet	2s	512 MB	Judgeable
Pretty printing arraysReprint the given brace array so each word and brace sits on its own line with two-space indent per nesting level.	Easy3	StackSimulation	No attempts yet	1s	64 MB	Judgeable
Fly SwatterFind the K by K placement that encloses the most flies in its strict interior and print the count with the winning border drawn.	Easy3	Prefix sumMatrix+1	No attempts yet	1s	64 MB	Judgeable
Resistor CircuitCompute the equivalent resistance of a nested series-parallel resistor circuit described by a bracketed string.	Easy3	StackMath	No attempts yet	1s	64 MB	Judgeable
Breed CountingGiven the breed of each cow in a row, report the count of each of the three breeds inside every query interval.	Easy3	Prefix sumArray	No attempts yet	2s	512 MB	Judgeable
Contaminated MilkFrom drink and sickness logs, keep each milk every sick person drank before falling sick and report the largest drinker count.	Easy3	SimulationBrute force	No attempts yet	2s	512 MB	Judgeable
Angry Cows (Bronze)Starting from the best bale, count how many bales explode as the blast radius grows by one each step.	Easy3	SimulationSorting	No attempts yet	2s	512 MB	Judgeable
Mowing the FieldSimulate the grid walk and report the smallest time gap between two visits to the same cell, or -1 when no cell repeats.	Easy3	SimulationHash map	No attempts yet	2s	512 MB	Judgeable
Balanced Fence PartitionPlace one vertical and one horizontal fence between grid points to minimize the largest cow count in the four regions.	Easy3	Brute forceSorting	No attempts yet	2s	512 MB	Judgeable
Diamond Collector (Bronze)Choose the largest group of diamonds whose sizes differ by at most K.	Easy3	SortingSliding window	No attempts yet	2s	512 MB	Judgeable
Bull in a China Shop (Bronze)Pick the two pieces from K candidates that shift without rotation to cover the original grid exactly once.	Easy3	Brute forceSimulation	No attempts yet	2s	512 MB	Judgeable
Younghoon the PranksterGiven a digit string where 1 and 6 are interchangeable and 2 and 7 are interchangeable, print its k-th candidate in lexicographic order or -1.	Easy3	CombinatoricsString	No attempts yet	1s	128 MB	Judgeable
Polynesiaglot (Small 1)Count length-L words over C consonants and V vowels in which each consonant is directly followed by a vowel, modulo 1000000007.	Easy3	Dynamic programmingCombinatorics	No attempts yet	5s	512 MB	Judgeable
PolynesiaglotCount length-L strings over C consonants and V vowels with no adjacent consonants and no trailing consonant, modulo 1e9+7.	Easy3	Dynamic programmingCombinatorics	No attempts yet	5s	512 MB	Judgeable
Polynesiaglot (Large)Count length-L words over C consonants and V vowels where every consonant is followed by a vowel, modulo 1e9+7.	Easy3	Dynamic programmingCombinatorics	No attempts yet	5s	512 MB	Judgeable
Lazy Spelling Bee (Small)Count distinct words formed by replacing each letter with itself or an adjacent letter of the target word.	Easy3	CombinatoricsString	No attempts yet	5s	512 MB	Judgeable
Dynamic Grid (Small)Count the edge-connected groups of 1s in a binary grid after each point update by flood fill.	Easy3	BFSGraph+1	No attempts yet	5s	512 MB	Judgeable
gRanks (Small)Rank every athlete by summing only their M highest weighted place points, breaking ties alphabetically with skipped ranks.	Easy3	SortingHash map+1	No attempts yet	5s	512 MB	Judgeable
gRanksRank athletes by summing each athlete's top M weighted placement scores and ordering by total, breaking ties alphabetically.	Easy3	SortingHash map+1	No attempts yet	5s	512 MB	Judgeable
Googol String (Small)Build the recursive 0/1 string defined by S with a middle 0 plus a switched reversal, then answer the Kth character for each test case.	Easy3	RecursionSimulation	No attempts yet	5s	512 MB	Judgeable
Bad Horse (Small 1)Decide for each test case whether members joined by troublesome pairs split into two groups with no pair in one group.	Easy3	GraphBFS	No attempts yet	5s	512 MB	Judgeable
Bad Horse (Small2)Decide whether members linked by troublesome pairs split into two groups with no pair inside one group.	Easy3	GraphBFS	No attempts yet	5s	512 MB	Judgeable
Captain Hammer (Small)Given launch speed and target distance, compute the smallest launch angle in degrees that lands exactly on the target.	Easy3	Math	No attempts yet	5s	512 MB	Judgeable
Sums of 1, 2, 3 (2)Find the k-th composition of n using parts 1, 2 and 3 in lexicographic order, or print -1 when it does not exist.	Easy3	BacktrackingDynamic programming	No attempts yet	1s	512 MB	Judgeable
H-IndexGiven N citation counts, compute the largest H with at least H papers cited at least H times.	Easy3	Sorting	No attempts yet	1s	256 MB	Judgeable
Crane Truck (Small)Run each crane program on 240 circular cells with wrapping crate counts and count the truck's forward and backward moves.	Easy3	SimulationImplementation	No attempts yet	10s	512 MB	Judgeable
Mushroom Monster (Small)Given plate counts at 10-second intervals, compute the minimum eaten under free eating and under a constant eating rate.	Easy3	SimulationGreedy	No attempts yet	5s	512 MB	Judgeable
Standing Ovation (Small)Given audience counts per shyness level, find the fewest extra friends to invite so everyone eventually stands and claps.	Easy3	Greedy	No attempts yet	5s	512 MB	Judgeable
Standing Ovation (Large)Find the fewest friends to add so every audience member stands as each shyness threshold is met in order.	Easy3	Greedy	No attempts yet	5s	512 MB	Judgeable
Sort a scrambled itinerary (Small)Rebuild each shuffled set of flight tickets into the single chain where each arrival matches the next departure.	Easy3	Hash mapGraph	No attempts yet	5s	512 MB	Judgeable
Sort a scrambled itinerary (Large)Rebuild the flight order by chaining tickets from the starting city that never appears as a destination.	Easy3	Hash map	No attempts yet	5s	512 MB	Judgeable
One move captures (small)Count all ordered pairs of chess pieces where one can capture the other in a single legal move with blocking.	Easy3	SimulationBrute force	No attempts yet	5s	512 MB	Judgeable
Captures in One MoveCount ordered capture pairs on an 8x8 board by applying each chess piece's capture rules with blocking for sliders.	Easy3	SimulationImplementation	No attempts yet	5s	512 MB	Judgeable
Super 2048 (Small)The program slides all tiles of an N by N 2048 board one move in the given direction, merging equal pairs once with leading tiles first.	Easy3	SimulationMatrix	No attempts yet	5s	512 MB	Judgeable
Super 2048 (Large)Slide every tile on an N by N 2048 board in the given direction, merging equal neighbours once per move.	Easy3	SimulationMatrix	No attempts yet	5s	512 MB	Judgeable
Sudoku Solution CheckerCheck whether each completed 9x9 grid has digits 1 to 9 exactly once in every row, column, and 3x3 box.	Easy3	MatrixHash map	No attempts yet	5s	512 MB	Judgeable
Sudoku Solution CheckerCheck whether each completed N-squared by N-squared grid has every row, column, and N by N block holding 1 to N-squared exactly once.	Easy3	MatrixHash map+1	No attempts yet	5s	512 MB	Judgeable
Meet and party (small)Choose an attendee home inside the given rectangles that minimizes the total Manhattan travel distance, breaking ties by smaller x then y.	Easy3	Brute force	No attempts yet	5s	512 MB	Judgeable
Read Phone Number (Large)Print the digit groups from the hyphen format aloud, replacing each run of equal digits with a count word such as double or triple.	Easy3	ImplementationString	No attempts yet	5s	512 MB	Judgeable
Bookshelf SortingSeparate books into odd and even worths, sort the odds up and the evens down, then refill each position with the matching owner.	Easy3	SortingArray	No attempts yet	5s	512 MB	Judgeable
Sorting the BookshelfSeparate the books by odd and even worth, sort the odd ones increasingly and the even ones decreasingly, then put each back on its owner labeled spots.	Easy3	SortingArray	No attempts yet	5s	512 MB	Judgeable
Cross the maze (Small)Simulate the left-hand wall-following robot for up to 10000 steps and report whether it reaches the exit with its path.	Easy3	Simulation	No attempts yet	5s	512 MB	Judgeable
Cross the maze (large)Simulate a left-hand wall-following robot in an N by N maze for up to 10000 steps and print the step count and path if it reaches the exit.	Easy3	SimulationMatrix	No attempts yet	5s	512 MB	Judgeable
Consonants (Small)Count the substrings of each name that contain at least n consecutive consonants.	Easy3	StringTwo pointers	No attempts yet	5s	512 MB	Judgeable
Hedgemony (Large)Simulate one left-to-right pass that trims each bush to the average of its neighbors when taller, then report the final height of bush N-1 with six decimals.	Easy3	SimulationMath	No attempts yet	5s	512 MB	Judgeable
Ocean View (Small)Destroy the fewest houses so the heights of the houses that remain strictly increase from the lake eastward.	Easy3	Brute forceArray	No attempts yet	5s	512 MB	Judgeable
Aerobics Mat PlacementPlace disc centers row by row with the given greedy rule along the longer side of the mat and print the coordinates.	Easy3	SimulationGreedy	No attempts yet	5s	512 MB	Judgeable
Aerobics (Large)Sort students by reach, largest first, then place them line by line on the mat following the prescribed packing rule.	Easy3	SimulationSorting	No attempts yet	5s	512 MB	Judgeable
Password RetypingGiven per-character correctness odds, pick backspaces or a restart to minimize expected keystrokes to finish the password.	Easy3	ProbabilityMath+1	No attempts yet	5s	512 MB	Judgeable
Speaking in Tongues (Small)Translate each Googlerese line back to English with the fixed substitution mapping derived from the given hints and example.	Easy3	Hash mapString	No attempts yet	5s	512 MB	Judgeable
Commute War (Small)Walk the single chain of hourly rides from home to the office, adding each wait, ride time, and geometric checkpoint delay for the expected arrival time.	Easy3	ProbabilitySimulation+1	No attempts yet	5s	512 MB	Judgeable
New Calendar (Small)Given months per year, days per month and days per week, count calendar rows when each month starts after the previous month and never shares a row.	Easy3	SimulationMath	No attempts yet	5s	512 MB	Judgeable
Equation restoration (Small)Fill each ? in an addition or subtraction equation with a digit so the equation holds and the whole string is lexicographically smallest.	Easy3	Brute forceString+1	No attempts yet	5s	512 MB	Judgeable
Snapper Chain (Small)Decide whether N chained toggle switches all turn on after K snaps, which lights the bulb.	Easy3	Bit manipulationSimulation	No attempts yet	5s	512 MB	Judgeable
Theme Park (Small)Groups board a k-seat coaster in queue order and rejoin the back after each run, so simulate R runs and add one euro per rider.	Easy3	SimulationQueue	No attempts yet	5s	512 MB	Judgeable
Perpetual Motion (Small)Count assignments of a direction to each oriented belt on a grid of at most 4 by 4 so no two lemmings land on the same square, modulo 1000003.	Easy3	Brute forceSimulation	No attempts yet	5s	512 MB	Judgeable
Mystery Square (Small)Fill each ? in the binary string with 0 or 1 so the result is a perfect square.	Easy3	Brute forceMath	No attempts yet	5s	512 MB	Judgeable
Square TilesDecide if the blue cells of a grid can be exactly covered by non-overlapping 2x2 tiles and print the tiling.	Easy3	GreedyMatrix+1	No attempts yet	5s	512 MB	Judgeable
Square Tiles (Large)For each test case, decide whether all blue cells can be tiled with non-overlapping 2x2 red tiles and print the tiled picture or Impossible.	Easy3	GreedyMatrix+1	No attempts yet	5s	512 MB	Judgeable
Perfect Harmony (Small)Pick the smallest frequency between L and H that divides or is divided by every given frequency, or report NO.	Easy3	Number theoryBrute force	No attempts yet	5s	512 MB	Judgeable
Ratings Percentage IndexGiven the win-loss matrix of every team, compute each team's RPI from win percentages and opponents' averages and print each as a reduced fraction.	Easy3	SimulationMath+1	No attempts yet	5s	512 MB	Judgeable
RPI (Large)Compute every team RPI rating from the win-loss schedule using own, opponents, and opponents-of-opponents win rates.	Easy3	SimulationMath	No attempts yet	5s	512 MB	Judgeable
Button-Pressing RobotsTwo robots walk through separate hallways in parallel and press one shared ordered list of buttons in the shortest total time.	Easy3	SimulationGreedy	No attempts yet	5s	512 MB	Judgeable
Two Button-Pressing RobotsTwo robots starting at button 1 share one ordered press sequence and move or press each second, so compute the minimum time to finish it.	Easy3	SimulationGreedy	No attempts yet	5s	512 MB	Judgeable
Magicka (Small)Simulate invocations in order, combining the last two list elements when a rule matches and clearing the whole list when opposed elements meet.	Easy3	SimulationStack	No attempts yet	5s	512 MB	Judgeable
Magicka Element CombiningInvoke each base element in order, merging the last two entries when they combine and clearing the list when opposed elements meet, then report the final list.	Easy3	SimulationStack	No attempts yet	5s	512 MB	Judgeable
Twibet (Small)Starting from each monk in turn, count how many monks hear a whisper that spreads from a monk to all direct and indirect followers.	Easy3	GraphDFS	No attempts yet	5s	512 MB	Judgeable
Building a House (Large)Find the area of the largest axis-aligned rectangle containing only grass or shrubs in a grid with fewer than 20 rock, water, or tree cells.	Easy3	Brute forcePrefix sum+1	No attempts yet	5s	512 MB	Judgeable
Grazing Goats (Small)Each of the two disks centered at the poles must cover the bucket point, and the answer is the overlap area of the smallest such disks.	Easy3	GeometryMath	No attempts yet	5s	512 MB	Judgeable
Rope IntranetCount the cable pairs that cross by sorting on the left height and counting opposite-ordered right heights.	Easy3	SortingBrute force	No attempts yet	5s	512 MB	Judgeable
Rope IntranetCount wire pairs that cross by sorting on one endpoint height and counting inverted pairs on the other.	Easy3	SortingBrute force	No attempts yet	5s	512 MB	Judgeable
File Fix-it (Small)Count the mkdir commands needed to create each requested path from its missing prefixes.	Easy3	TrieString	No attempts yet	5s	512 MB	Judgeable
File Fix-it (Large)Count the directories along each wanted path that do not exist yet and report how many mkdir calls they need.	Easy3	TrieString	No attempts yet	5s	512 MB	Judgeable
Rotate the BoardRotate the board 90 degrees clockwise, let every piece fall to the lowest empty cell, then report whether Red, Blue, both, or neither has K in a row.	Easy3	SimulationMatrix+1	No attempts yet	5s	512 MB	Judgeable
Board RotationRotate each board 90 degrees clockwise, let gravity settle the pieces, then report whether Red, Blue, both, or neither has K in a row.	Easy3	SimulationMatrix+1	No attempts yet	5s	512 MB	Judgeable
Theme Park (Small)Groups board a k-seat coaster in queue order without skipping, riders rejoin the back, and total earnings over R runs are computed.	Easy3	SimulationQueue	No attempts yet	5s	512 MB	Judgeable