Problems

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Total results29,476 problems

Neighborhoods in Graphs
Easy3
BFS, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Theseus and the Minotaur
Easy3
Simulation, Hash map
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
The Trojan Horse
Easy3
DFS, Simulation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Maximum Subarray Sum
Easy3
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Counting Communication Groups
Easy3
Union-find, Geometry
No attempts yet
Time limit
8s
Memory limit
256 MB
Judgeable
Memory
Easy3
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Corn maze
Easy3
BFS, Matrix
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Chain Disappearance Puzzle
Easy3
Simulation, Matrix+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Real Estate Auction
Easy3
Sliding window, Two pointers+1
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Henry
Easy3
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Algebraic Teamwork
Easy3
Combinatorics, Math
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Gold Rush
Easy3
Bit manipulation, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Ribbon
Easy3
Number theory
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Tigger's bounces
Easy3
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cookie Farm
Easy3
Greedy, Math
No attempts yet
Time limit
10s
Memory limit
64 MB
Judgeable
Spiral Area Division
Easy3
Geometry, Simulation+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Maximal Sum
Easy3
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Fun House
Easy3
Simulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Word Cloud
Easy3
Simulation, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Pantun Grader
Easy3
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Spokes Wheel
Easy3
Bit manipulation, Brute force
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Buffcraft
Easy3
Sorting, Greedy+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Grave
Easy3
Geometry, Implementation
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
The Cost of Moving
Easy3
Sorting, Hash map
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Two Tower Mod 3
Easy3
Math, Number theory
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Yet Satisfiability Again
Easy3
Brute force, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Valid Parenthesis Count
Easy3
Combinatorics, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Line Up Back Steps
Easy3
Simulation, Brute force
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Islands in the Data Stream
Easy3
Brute force, Array
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Happy Prime
Easy3
Simulation, Hash map+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Rank Order
Easy3
Sorting
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Algorist Club
Easy3
Simulation, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Eureka Theorem
Easy3
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Permutation Cycles
Easy3
Graph, DFS
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Time Travel
Easy3
Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
XOR Range
Easy3
Bit manipulation, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Rolling Encryption
Easy3
Sliding window, Array+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Let's make some space
Easy3
Brute force, Sorting
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cross Flip
Easy3
Brute force, Simulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Goldbach's Conjecture
Easy3
Number theory, Brute force
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Four Fours
Easy3
Brute force, Implementation
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Even Up Solitaire
Easy3
Stack, Greedy
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Good morning!
Easy3
Brute force, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Refueling Stops
Easy3
Greedy, Simulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Hyacinth frequency assignment
Easy3
Tree, DFS+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Judging Troubles
Easy3
Hash map
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
The Spoiled Marathoner
Easy3
Hash map
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
DOM TV Channels
Easy3
Graph, Simulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Skyscraper Silhouette
Easy3
Simulation, Array+1
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Knockout Racing
Easy3
Simulation, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Ideal Scoreboard
Easy3
Simulation, Sorting
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Multiple of 30
Easy3
Sorting, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
A Population of Rabbits
Easy3
Dynamic programming, Simulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Marathon 1
Easy3
Greedy, Array+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cow Jog
Easy3
Greedy, Array
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Hamza
Easy3
Hash map, Array
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Compo
Easy3
Sorting, Intervals
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cable Cleanup
Easy3
Graph, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Prof. Ossama's budget
Easy3
Math, String
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Meteor
Easy3
Simulation, Matrix+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
COW
Easy3
Dynamic programming, String
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Big Integer Addition
Easy3
String, Simulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Bessie Gets Even
Easy3
Brute force, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Zero Stack
Easy3
Stack
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Jerseys
Easy3
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Largest Stock Price Decline
Easy3
Array, Greedy+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Iron Bars
Easy3
Stack
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Sort by Age
Easy3
Sorting
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Number Cards
Easy3
Hash map, Binary search
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Number Cards 2
Easy3
Hash map
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Korean, English, math
Easy3
Sorting
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Fibonacci Numbers 4
Easy3
Dynamic programming, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Stack
Easy3
Stack
No attempts yet
Time limit
0.5s
Memory limit
256 MB
Judgeable
Matrix power
Easy3
Matrix, Divide and conquer
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Stair Number Count
Easy3
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Queue
Easy3
Queue
No attempts yet
Time limit
0.5s
Memory limit
256 MB
Judgeable
Legacy Code
Easy3
Graph, BFS
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Milling machines
Easy3
Simulation, Implementation
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Deque
Easy3
Queue, Implementation
No attempts yet
Time limit
0.5s
Memory limit
256 MB
Judgeable
Sort without duplicates
Easy3
Sorting
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Minimum value
Easy3
Segment tree
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Your life
Easy3
BFS, Shortest path+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
BASE64 Encoding
Easy3
Bit manipulation, String+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
BASE64 Decoding
Easy3
Implementation, String+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Base32 Encoding
Easy3
Bit manipulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
BASE32 Decoding
Easy3
Bit manipulation, String+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
All Permutations
Easy3
Backtracking, Recursion
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Simple Arithmetic
Easy3
Stack, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Heading to World Finals
Easy3
Sorting, Hash map
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sorting Numbers 3
Easy3
Sorting, Array
No attempts yet
Time limit
5s
Memory limit
8 MB
Judgeable
Printing Stars - 19
Easy3
Recursion, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
K-th smallest number
Easy3
Sorting
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Master of copy and paste
Easy3
Greedy, String matching
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Short Phrase
Easy3
Simulation, Brute force
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Coins 0
Easy3
Greedy
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Moving
Easy3
Dynamic programming, Matrix
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Binomial Coefficient 2
Easy3
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Buying cards
Easy3
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Largest Sum Increasing Subsequence
Easy3
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Ascending Numbers
Easy3
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Neighborhoods in GraphsCount the distinct vertices at distance 1 or 2 from a query vertex in an undirected graph, excluding the vertex itself.	Easy3	BFSGraph	No attempts yet	1s	256 MB	Judgeable
Theseus and the MinotaurWalk each path on the grid, toggle every used corridor, and answer Yes when no corridor stays unwound.	Easy3	SimulationHash map	No attempts yet	1s	256 MB	Judgeable
The Trojan HorseMark all cells visited by patrol routes on an h by w grid, then count 4-connected unvisited regions with at least s cells.	Easy3	DFSSimulation+1	No attempts yet	1s	256 MB	Judgeable
Maximum Subarray SumFor each test case, find the maximum sum over all contiguous subarrays of the given integer array.	Easy3	Dynamic programmingArray	No attempts yet	1s	256 MB	Judgeable
Counting Communication GroupsCount the connected groups of camps whose circular communication areas touch or overlap.	Easy3	Union-findGeometry	No attempts yet	8s	256 MB	Judgeable
MemoryPlay Memory with 50 face-down cards (25 letter pairs) by calling faceup(C); find each matching pair so Jack collects all 25 candies.	Easy3	SimulationImplementation+2	No attempts yet	1s	256 MB	Judgeable
Corn mazeStarting from the single entrance on the border, move through open cells in four directions and report the farthest shortest distance.	Easy3	BFSMatrix	No attempts yet	1s	256 MB	Judgeable
Chain Disappearance PuzzleRepeatedly remove horizontal runs of three or more equal digits from a 5-column board, drop stones above into gaps, and sum the removed digits.	Easy3	SimulationMatrix+1	No attempts yet	1s	256 MB	Judgeable
Real Estate AuctionCount the blocks of consecutive houses priced 2, 3, 4 and upward whose prices sum to exactly N.	Easy3	Sliding windowTwo pointers+1	No attempts yet	10s	256 MB	Judgeable
HenryRun the greedy unit-fraction expansion of each given fraction and print its last denominator.	Easy3	GreedyMath+1	No attempts yet	1s	256 MB	Judgeable
Algebraic TeamworkFor each given n, count the permutations of n elements that are not idempotent modulo 1000000007.	Easy3	CombinatoricsMath	No attempts yet	3s	256 MB	Judgeable
Gold RushSplit a bar of weight 2 to the n into halves with the fewest cuts so two shares of weights a and b can be formed.	Easy3	Bit manipulationMath	No attempts yet	1s	256 MB	Judgeable
RibbonAfter dropping the dirty inch at each end of every roll, find the longest common piece length that uses up every roll and count the total pieces.	Easy3	Number theory	No attempts yet	2s	256 MB	Judgeable
Tigger's bouncesCount length-K walks on an R by C grid where each step stays put or moves to a side neighbor, summed over all starts, modulo P per query.	Easy3	Dynamic programmingCombinatorics	No attempts yet	1s	256 MB	Judgeable
Cookie FarmYou start at rate 2 and buy farms to reach X cookies in the least total time.	Easy3	GreedyMath	No attempts yet	10s	64 MB	Judgeable
Spiral Area DivisionGiven up to 100 points in an 80 by 80 square cut into 15 labeled pieces by alternating 3-to-1 splits, output the label containing each point.	Easy3	GeometrySimulation+1	No attempts yet	1s	64 MB	Judgeable
Maximal SumFind the contiguous block of edge weights with the largest sum and print its endpoints, or print no good path when the best sum is not positive.	Easy3	Dynamic programmingArray	No attempts yet	1s	64 MB	Judgeable
Fun HouseTrace a beam from the entry through slash mirrors on a grid and mark the first wall it reaches as the exit.	Easy3	Simulation	No attempts yet	1s	256 MB	Judgeable
Word CloudCompute each word font size from its count, pack words in order into rows of width W, and output the summed row heights.	Easy3	SimulationMath	No attempts yet	1s	256 MB	Judgeable
Pantun GraderScore the first four verses of each pantun on syllable count, rhyme pairs and matching lengths, then subtract penalties for extra verses.	Easy3	StringImplementation+1	No attempts yet	1s	256 MB	Judgeable
Spokes WheelFind the fewest left or right rotations that turn the first 32-spoke binary pattern into the second, or report that it is impossible.	Easy3	Bit manipulationBrute force	No attempts yet	1s	256 MB	Judgeable
BuffcraftPick at most k direct and percentage buffs so the boosted base times the percentage multiplier is as large as possible.	Easy3	SortingGreedy+1	No attempts yet	2s	256 MB	Judgeable
GraveDecide whether a fixed-orientation w by h rectangle fits inside the graveyard without entering the chapel interior.	Easy3	GeometryImplementation	No attempts yet	2s	256 MB	Judgeable
The Cost of MovingSort each list of unique product names alphabetically and sum how far every item moves from its original slot.	Easy3	SortingHash map	No attempts yet	3s	256 MB	Judgeable
Two Tower Mod 3Find the remainder of a power tower of H twos divided by 3.	Easy3	MathNumber theory	No attempts yet	1s	256 MB	Judgeable
Yet Satisfiability AgainDecide whether a CNF formula over at most 20 variables and 100 clauses has an assignment that satisfies every clause.	Easy3	Brute forceBit manipulation	No attempts yet	1s	256 MB	Judgeable
Valid Parenthesis CountCount the distinct correct parenthesis strings of length L for each test case, modulo 1000000007.	Easy3	CombinatoricsDynamic programming+1	No attempts yet	2s	256 MB	Judgeable
Line Up Back StepsYou simulate the lineup rule for 20 students arriving in a given order and count the total backward steps.	Easy3	SimulationBrute force	No attempts yet	1s	256 MB	Judgeable
Islands in the Data StreamCount the contiguous blocks strictly above both bordering values in each 12-number sequence with zeros at both ends.	Easy3	Brute forceArray	No attempts yet	1s	256 MB	Judgeable
Happy PrimeDecide whether each given number is both prime and happy under repeated digit-square sums, and print the result with its case number.	Easy3	SimulationHash map+1	No attempts yet	1s	256 MB	Judgeable
Rank OrderCompare two judges' score lists by ranked order and report the highest place where the ranked competitors differ, or agree when all match.	Easy3	Sorting	No attempts yet	3s	256 MB	Judgeable
Algorist ClubThe program gives each unfamiliar pair in input order the lowest free of max-degree-plus-one slots and prints zeros when a pair fits nowhere.	Easy3	SimulationGraph	No attempts yet	1s	256 MB	Judgeable
Eureka TheoremGiven K from 3 to 1000, print 1 when it equals the sum of exactly three triangular numbers and 0 otherwise.	Easy3	Brute forceMath	No attempts yet	1s	256 MB	Judgeable
Permutation CyclesCount the disjoint directed cycles in the permutation given in each test case.	Easy3	GraphDFS	No attempts yet	1s	256 MB	Judgeable
Time TravelTwo watches losing a and b seconds per day start at midnight, and you report the first displayed time they agree on, rounded to the minute.	Easy3	Math	No attempts yet	1s	256 MB	Judgeable
XOR RangeCompute the XOR of all integers from S to F for each of up to 1000 test cases.	Easy3	Bit manipulationMath	No attempts yet	1s	256 MB	Judgeable
Rolling EncryptionEncrypt a lowercase string by leaving the first k letters unchanged and shifting each later letter by the most frequent of the k original letters before it.	Easy3	Sliding windowArray+1	No attempts yet	1s	256 MB	Judgeable
Let's make some spaceList in increasing order every room width obtainable by raising any subset of the given partition positions.	Easy3	Brute forceSorting	No attempts yet	1s	256 MB	Judgeable
Cross FlipFind the fewest cross-shaped clicks that turn an all-white 3x3 board into each given target pattern.	Easy3	Brute forceSimulation	No attempts yet	1s	256 MB	Judgeable
Goldbach's ConjectureCount and list every pair of primes that sums to each given even number up to 32000.	Easy3	Number theoryBrute force	No attempts yet	2s	256 MB	Judgeable
Four FoursUsing exactly four 4s joined by three operators from *, +, -, /, print the lexicographically first expression equal to each query value or no solution.	Easy3	Brute forceImplementation	No attempts yet	2s	256 MB	Judgeable
Even Up SolitaireRepeatedly remove adjacent card pairs with an even sum so that as few cards as possible remain.	Easy3	StackGreedy	No attempts yet	2s	256 MB	Judgeable
Good morning!Find the nonnegative integer closest to k whose consecutive keypad digits never move up or left, breaking ties toward the smaller number.	Easy3	Brute forceImplementation	No attempts yet	1s	256 MB	Judgeable
Refueling StopsSimulate the farthest-reachable greedy rule over ordered stations to list minimum refuel stops or report running out of petrol.	Easy3	GreedySimulation	No attempts yet	1s	256 MB	Judgeable
Hyacinth frequency assignmentAssign one frequency to each edge of a tree by the stated DFS rule so each node uses at most two frequencies.	Easy3	TreeDFS+1	No attempts yet	1s	256 MB	Judgeable
Judging TroublesCount how many results appear in both judging lists when pairs share the same string.	Easy3	Hash map	No attempts yet	1s	256 MB	Judgeable
The Spoiled MarathonerFind the one entrant name that appears in the list of N entrants but is missing from the N-1 finishers.	Easy3	Hash map	No attempts yet	1s	256 MB	Judgeable
DOM TV ChannelsPensioners switch the TV from each hated channel to the youngest hater's favorite, and you count switches until the channel stabilizes or repeats.	Easy3	GraphSimulation	No attempts yet	1s	256 MB	Judgeable
Skyscraper SilhouetteRebuild the skyline picture from N ground-based rectangles, mark the border cells, and report the perimeter without the ground side.	Easy3	SimulationArray+1	No attempts yet	1s	32 MB	Judgeable
Knockout RacingCount the cars whose back-and-forth motion between two points puts them inside each queried interval at the given time.	Easy3	SimulationMath	No attempts yet	1s	256 MB	Judgeable
Ideal ScoreboardTrack contest solves in time order and report the interval during which every team and every problem has a solve but none has all.	Easy3	SimulationSorting	No attempts yet	2s	256 MB	Judgeable
Multiple of 30Rearrange all digits of N into the largest number divisible by 30, or print -1 when impossible.	Easy3	SortingMath	No attempts yet	1s	256 MB	Judgeable
A Population of RabbitsCount rabbit pairs alive in month M given lifespan D and breeding ages up to R, starting from one newborn pair.	Easy3	Dynamic programmingSimulation	No attempts yet	1s	256 MB	Judgeable
Marathon 1Run checkpoints 1 to N in order while skipping exactly one middle checkpoint to minimize the total Manhattan distance.	Easy3	GreedyArray+1	No attempts yet	1s	256 MB	Judgeable
Cow JogCount how many groups remain when faster cows behind slow down to match the slowest cow ahead of them.	Easy3	GreedyArray	No attempts yet	1s	256 MB	Judgeable
HamzaFind the shortest prefix of the category list that contains every distinct category appearing in the whole list.	Easy3	Hash mapArray	No attempts yet	1s	256 MB	Judgeable
CompoCount the pairs of contests whose inclusive time ranges overlap in each test case.	Easy3	SortingIntervals	No attempts yet	1s	256 MB	Judgeable
Cable CleanupFor each test case, keep N minus 1 of the M cables that join N computers into one network and print how many cables go.	Easy3	GraphMath	No attempts yet	1s	256 MB	Judgeable
Prof. Ossama's budgetEach test case asks for the remainder when a fund N with up to one million digits is divided by X.	Easy3	MathString	No attempts yet	1s	256 MB	Judgeable
MeteorShift the connected meteor cells straight down until they rest on the ground and print the final grid.	Easy3	SimulationMatrix+1	No attempts yet	1s	256 MB	Judgeable
COWCount the subsequences equal to COW in a string of C, O, and W up to length 100000.	Easy3	Dynamic programmingString	No attempts yet	1s	256 MB	Judgeable
Big Integer AdditionAdd two decimal integers with up to 100000 digits given on one line and print their exact sum.	Easy3	StringSimulation	No attempts yet	1s	256 MB	Judgeable
Bessie Gets EvenCount assignments of listed values to seven letters that make the product (B+E+S+S+I+E)(G+O+E+S)(M+O+O) even.	Easy3	Brute forceCombinatorics+1	No attempts yet	1s	256 MB	Judgeable
Zero StackNumbers are pushed onto a ledger and each zero erases the most recent entry, so report the sum of the remaining numbers.	Easy3	Stack	No attempts yet	1s	256 MB	Judgeable
JerseysEach player wants one numbered jersey in a minimum size, and the goal is to satisfy as many players as possible.	Easy3	GreedySorting	No attempts yet	1s	256 MB	Judgeable
Largest Stock Price DeclineGiven up to a million prices from a sine-cosine formula, find the largest drop from an earlier price to a later one.	Easy3	ArrayGreedy+1	No attempts yet	5s	256 MB	Judgeable
Iron BarsGiven a parenthesis string encoding bars and lasers, count the total bar pieces cut by the lasers.	Easy3	Stack	No attempts yet	1s	256 MB	Judgeable
Sort by AgeSort N members by increasing age, keeping earlier join order for equal ages.	Easy3	Sorting	No attempts yet	3s	256 MB	Judgeable
Number CardsCheck each of M query integers against a set of N owned cards and print 1 for a match and 0 otherwise.	Easy3	Hash mapBinary search	No attempts yet	2s	256 MB	Judgeable
Number Cards 2Count how many of N owned cards equal each of M query integers and print the counts in order.	Easy3	Hash map	No attempts yet	1s	256 MB	Judgeable
Korean, English, mathSort N students by Korean score descending, English ascending, math descending, then name in ASCII order and print the names.	Easy3	Sorting	No attempts yet	1s	256 MB	Judgeable
Fibonacci Numbers 4Compute the nth Fibonacci number for n up to 10000 using arbitrary-precision arithmetic.	Easy3	Dynamic programmingImplementation	No attempts yet	1s	256 MB	Judgeable
StackProcess push, pop, size, empty, and top commands on an integer stack and print each result.	Easy3	Stack	No attempts yet	0.5s	256 MB	Judgeable
Matrix powerCompute the N by N matrix A raised to power B, with each entry reduced modulo 1000.	Easy3	MatrixDivide and conquer	No attempts yet	1s	256 MB	Judgeable
Stair Number CountCount length-N numbers with no leading zero where adjacent digits differ by 1, modulo 1,000,000,000.	Easy3	Dynamic programming	No attempts yet	1s	256 MB	Judgeable
QueueProcess a sequence of push, pop, size, empty, front, and back commands on an integer queue and print each result.	Easy3	Queue	No attempts yet	0.5s	256 MB	Judgeable
Legacy CodeCount methods unreachable from any PROGRAM method given each method and its direct callers.	Easy3	GraphBFS	No attempts yet	1s	256 MB	Judgeable
Milling machinesThe program cuts each workpiece column down to the lowest cutter height from any step and prints the heights that remain.	Easy3	SimulationImplementation	No attempts yet	2s	256 MB	Judgeable
DequeProcess up to 10000 push, pop, size, empty, front and back commands on an integer deque and print each query result.	Easy3	QueueImplementation	No attempts yet	0.5s	256 MB	Judgeable
Sort without duplicatesSort N integers in ascending order and print each distinct value once, separated by spaces.	Easy3	Sorting	No attempts yet	1s	256 MB	Judgeable
Minimum valueAnswer up to 100,000 range minimum queries over a static array of up to 100,000 integers.	Easy3	Segment tree	No attempts yet	1s	256 MB	Judgeable
Your lifeFind the fewest directed moves from node 1 to node N in a graph where every edge goes forward, or report -1 when the goal is unreachable.	Easy3	BFSShortest path+1	No attempts yet	1s	256 MB	Judgeable
BASE64 EncodingEncode the given alphanumeric string into BASE64 by regrouping its bytes into 6-bit values with '=' padding.	Easy3	Bit manipulationString+1	No attempts yet	1s	256 MB	Judgeable
BASE64 DecodingDecode a Base64 string using the standard alphabet and padding back into the original alphanumeric text.	Easy3	ImplementationString+1	No attempts yet	1s	256 MB	Judgeable
Base32 EncodingConvert the input string to bytes and print its Base32 encoding with the standard alphabet and padding.	Easy3	Bit manipulationImplementation+1	No attempts yet	1s	256 MB	Judgeable
BASE32 DecodingPrint the original string S from its given Base32 encoding with padding.	Easy3	Bit manipulationString+1	No attempts yet	1s	256 MB	Judgeable
All PermutationsPrint every permutation of the numbers 1 to N in lexicographic order, one per line.	Easy3	BacktrackingRecursion	No attempts yet	1s	256 MB	Judgeable
Simple ArithmeticEvaluate single-digit expressions with usual precedence and floor division, printing WRONG INPUT for bad forms or division by zero.	Easy3	StackSimulation+1	No attempts yet	1s	128 MB	Judgeable
Heading to World FinalsRank all teams by solved problems, then penalty, and print the best team from each of the top K universities.	Easy3	SortingHash map	No attempts yet	1s	128 MB	Judgeable
Sorting Numbers 3Sort up to 10,000,000 integers no greater than 10,000 in ascending order, one per line.	Easy3	SortingArray	No attempts yet	5s	8 MB	Judgeable
Printing Stars - 19Print the N-level nested square star figure that the sample cases define.	Easy3	RecursionImplementation	No attempts yet	1s	256 MB	Judgeable
K-th smallest numberSort the N given integers in ascending order and print the element at position K.	Easy3	Sorting	No attempts yet	2s	512 MB	Judgeable
Master of copy and pasteHanshin builds a target string by typing one character at a time or pasting a fixed clipboard string, and the task asks for the minimum total time.	Easy3	GreedyString matching	No attempts yet	2s	256 MB	Judgeable
Short PhraseFind the earliest starting word of a contiguous block whose words split into five groups totaling 5, 7, 5, 7, and 7 letters.	Easy3	SimulationBrute force	No attempts yet	1s	256 MB	Judgeable
Coins 0Pay exactly K with the fewest coins from denominations where each divides the next.	Easy3	Greedy	No attempts yet	1s	256 MB	Judgeable
MovingJungyu collects the most candy possible walking from the top-left room to the bottom-right room with right, down, and diagonal moves.	Easy3	Dynamic programmingMatrix	No attempts yet	1s	256 MB	Judgeable
Binomial Coefficient 2Compute the binomial coefficient C(N, K) modulo 10007 for N up to 1000.	Easy3	Dynamic programmingCombinatorics	No attempts yet	1s	256 MB	Judgeable
Buying cardsGiven pack prices P_1 to P_N, choose packs whose card counts sum to exactly N to maximize the total price.	Easy3	Dynamic programming	No attempts yet	1s	256 MB	Judgeable
Largest Sum Increasing SubsequencePick elements in order so each is larger than the last and their sum is as large as possible.	Easy3	Dynamic programmingArray	No attempts yet	1s	256 MB	Judgeable
Ascending NumbersCount length-N digit strings, leading zeros allowed, whose digits never decrease left to right, modulo 10007.	Easy3	Dynamic programmingCombinatorics	No attempts yet	1s	256 MB	Judgeable