Problems

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Total results29,471 problems

Bank Robbery 1
Easy3
Hash map, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Bank Robbery 2
Easy3
Hash map, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Intelligent Game
Easy3
Array, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Finalists
Easy3
Implementation, Sorting+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Jumping Frog
Easy3
Dynamic programming, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Come Minion!
Easy3
Graph, BFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Happy Hiking Grounds
Easy3
BFS, Tree
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Call Me Maybe
Easy3
Hash map, Array
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Sorry About That, Chief!
Easy3
Number theory, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Knight Moves: Gold Edition
Easy3
BFS, Matrix
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tram
Easy3
Sorting, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Students and Mentors
Easy3
Sorting, Binary search
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Sort the Fabrics
Easy3
Sorting, Implementation
No attempts yet
Time limit
20s
Memory limit
1024 MB
Judgeable
1-Player Concentration
Easy3
Simulation, Hash map+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Neighbor
Easy3
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Pilot Rating
Easy3
Sorting, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Semmy
Easy3
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Orient the Edges
Easy3
Math, Combinatorics
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Field Navigation
Easy3
BFS, Matrix+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Histogram Fencing
Easy3
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Holes
Easy3
Matrix, BFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Painting Houses
Easy3
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
ReWord-wrap
Easy3
String, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Seasons
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Math
Easy3
Implementation, String+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Word
Easy3
Matrix, String matching+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rain
Easy3
Array, Two pointers
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Reverse
Easy3
String, Two pointers+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rain Boots
Easy3
Shortest path, BFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Best Seller
Easy3
Sorting, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Why does this guy love 1122 so much?
Easy3
Implementation, Binary search
No attempts yet
Time limit
1.122s
Memory limit
1122 MB
Judgeable
Second Numbers
Easy3
Math, Number theory+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Color Mixing
Easy3
Prefix sum, Array
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
T-Shirts
Easy3
Sorting, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Programs
Easy3
Greedy, Sorting+1
No attempts yet
Time limit
12s
Memory limit
1024 MB
Judgeable
Albo psikus!
Easy3
Prefix sum, Array
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Boards
Easy3
Sorting, Greedy
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Writers
Easy3
String, Hash map
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Uniform Maker
Easy3
Greedy, String+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Badstrand
Easy3
Sliding window, Array+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Spotify Connect
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Horse Jumping
Easy3
BFS, Graph+1
No attempts yet
Time limit
6s
Memory limit
1024 MB
Judgeable
Hostel
Easy3
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
IP Addresses
Easy3
Brute force, String+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sorting the Playlist
Easy3
Array, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rövarspråket
Easy3
String, Two pointers
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Limousine
Easy3
Greedy, Sorting
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
The Bus Card
Easy3
Greedy, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Family Reunion
Easy3
Tree, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Gourmet
Easy3
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Group Division
Easy3
Union-find, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tournament
Easy3
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lineup
Easy3
Backtracking, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Will Rogers Phenomenon
Easy3
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Clock
Easy3
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Plankan
Easy3
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cow College
Easy3
Sorting, Greedy
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Cow Phrasebook
Easy3
Hash map, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Alignment of the Planets
Easy3
Geometry, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Satellite Photographs
Easy3
BFS, Matrix
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Max Factor
Easy3
Number theory, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Checking an Alibi
Easy3
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Out of Hay
Easy3
Minimum spanning tree, Union-find+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Part Acquisition
Easy3
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Feed Accounting
Easy3
Simulation, Prefix sum
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bovine Ballroom Dancing
Easy3
Sorting, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Middle Squares
Easy3
Simulation, Hash map
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Leapcow
Easy3
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Romeo Meets Juliet
Easy3
Sliding window, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bovine Math Geniuses
Easy3
Simulation, Hash map
No attempts yet
Time limit
1s
Memory limit
16 MB
Judgeable
Strolling Cows
Easy3
Graph, Topological sort
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Round of 16 and Queries
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Wiggle Numbers
Easy3
Simulation, Hash map
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Extra Krunch
Easy3
String, Hash map+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Trapped
Easy3
BFS, Graph
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Metric Matrices
Easy3
Brute force, Matrix+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Spinning Wheels
Easy3
Brute force, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Entry Records
Easy3
Hash map, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bessie Come Home
Easy3
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Agri-Net
Easy3
Minimum spanning tree, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Unique Quotients
Easy3
Brute force, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Checks
Easy3
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Long Multiplication
Easy3
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Tamworth Two
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cows in Bed
Easy3
Brute force, Hash map
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sum25
Easy3
Brute force, Backtracking
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cows in Bed
Easy3
Brute force, Hash map+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Highest Mountain
Easy3
Matrix, BFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Negative Number Bases
Easy3
Math, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Crazy Time
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Shrine for the Gods
Easy3
Prefix sum, Array
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Dissimilar numbers
Easy3
Math, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Multiple Segments
Easy3
Prefix sum, Hash map+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Class
Easy3
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Against Bertrand's Postulate
Easy3
Sorting, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Distinct Squares
Easy3
Math, Binary search
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Spiral
Easy3
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Two Gifts
Easy3
Two pointers, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Frames
Easy3
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Interesting Partitions
Easy3
Backtracking, Recursion
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Bank Robbery 1Given banks at positions X_i with open times T_i and rewards C_i, find the maximum total reward Siwoo can collect on one rightward path.	Easy3	Hash mapImplementation	No attempts yet	1s	256 MB	Judgeable
Bank Robbery 2Given banks at positions X_i that open at time T_i, find the maximum total money Siwoo can rob while moving only rightward from a chosen start.	Easy3	Hash mapImplementation	No attempts yet	1s	256 MB	Judgeable
Intelligent GameGiven n pebbles on a 101 by 101 grid, find the largest number of pebbles that land on another pebble under a single nonzero translation.	Easy3	ArrayBrute force	No attempts yet	1s	1024 MB	Judgeable
FinalistsGiven the World Finals slot count N and six regionals' statistics, compute how many slots the Taiwan regional receives under the site-score allocation rules.	Easy3	ImplementationSorting+1	No attempts yet	3s	1024 MB	Judgeable
Jumping FrogGiven a row of cells where some are blocked, find the fewest jumps of at most d+1 positions needed to go from the first cell to the last, or 0 if impossible.	Easy3	Dynamic programmingString	No attempts yet	1s	1024 MB	Judgeable
Come Minion!For each map, decide whether location 0 can reach location n-1 using only routes whose trial is not on the ninja's banned list.	Easy3	GraphBFS+1	No attempts yet	1s	1024 MB	Judgeable
Happy Hiking GroundsGiven a weighted tree rooted at A, find the total walking distance of a BFS hike where Arup returns to the parent after each child visit.	Easy3	BFSTree	No attempts yet	1s	1024 MB	Judgeable
Call Me MaybeFor each lyric word, pick speech occurrences in round-robin order, or report NOT POSSIBLE if any lyric word never appears in the speeches.	Easy3	Hash mapArray	No attempts yet	2s	1024 MB	Judgeable
Sorry About That, Chief!For each value from 2 to 10,000, report whether it is prime or how far it is from the nearest prime.	Easy3	Number theoryBrute force	No attempts yet	1s	1024 MB	Judgeable
Knight Moves: Gold EditionFind the fewest knight moves between two squares on an N by N board, where N is at most 20.	Easy3	BFSMatrix	No attempts yet	1s	1024 MB	Judgeable
TramGiven each station's time from station 1 (Patrik) or from an earlier station (Josip), find the pair of stations with the smallest time gap.	Easy3	SortingArray	No attempts yet	1s	1024 MB	Judgeable
Students and MentorsFor each student, find the highest rating among other students that is at most twice their own rating, or -1 if no such student exists.	Easy3	SortingBinary search	No attempts yet	Not set	1024 MB	Judgeable
Sort the FabricsCount the fabrics that land in the same position when sorted by color (then ID) and by durability (then ID).	Easy3	SortingImplementation	No attempts yet	20s	1024 MB	Judgeable
1-Player ConcentrationCount the turns needed to clear all paired cards from an H x W grid, flipping cards in snake order while remembering every revealed card.	Easy3	SimulationHash map+1	No attempts yet	2s	1024 MB	Judgeable
NeighborGiven two fractions, reduce their positive difference and output it if the numerator is 1, otherwise output NOT NEIGHBORS.	Easy3	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Pilot RatingPair n pilots into two-person teams so that the weakest team's total rating is as large as possible, and print that value.	Easy3	SortingGreedy+1	No attempts yet	1s	1024 MB	Judgeable
SemmyDecode semaphore flag signal sequences into English text and encode English phrases back into signals, with # marking spaces.	Easy3	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Orient the EdgesCount the acyclic orientations of a complete graph on n labeled points, modulo 1000000007, for n up to 1,000,000.	Easy3	MathCombinatorics	No attempts yet	1s	1024 MB	Judgeable
Field NavigationFind the fewest tools to carry so you can walk from the start to the hat, where each tool clears one obstacle type (grass, branches, or rocks).	Easy3	BFSMatrix+1	No attempts yet	1s	1024 MB	Judgeable
Histogram FencingFor each histogram-shaped farm, given bar widths and heights, compute the total perimeter that needs fencing.	Easy3	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
HolesCount the connected sections of empty cells in a walled grid, and the total number of empty cells.	Easy3	MatrixBFS+1	No attempts yet	1s	1024 MB	Judgeable
Painting HousesGiven K, P, and X, find the minimum of m times X plus P times K divided by m over positive integers m, the number of painters.	Easy3	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
ReWord-wrapGiven lines of text and a width w, rewrap the words so no line exceeds w characters without splitting any word.	Easy3	StringGreedy+1	No attempts yet	1s	1024 MB	Judgeable
SeasonsGiven a start date and a distance, find the arrival date when Marie walks 3, 5, or 1 miles a day depending on the month.	Easy3	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
MathEvaluate each integer expression that uses + - * / % with standard operator precedence and print its integer value.	Easy3	ImplementationString+1	No attempts yet	1s	1024 MB	Judgeable
WordFor each grid, count how many times the word "word" appears when reading in any of the eight directions, including backwards.	Easy3	MatrixString matching+1	No attempts yet	1s	1024 MB	Judgeable
RainFor each data set of building heights, compute the total amount of rainwater trapped between and above the buildings.	Easy3	ArrayTwo pointers	No attempts yet	1s	1024 MB	Judgeable
ReverseFor each input line, reverse the order of the words that start with a vowel and leave consonant-initial words in their original positions.	Easy3	StringTwo pointers+1	No attempts yet	1s	1024 MB	Judgeable
Rain BootsFind the fewest muddy puddles ('M') you must step on to get from S to E in each 8x8 grid of the nearby area.	Easy3	Shortest pathBFS+1	No attempts yet	1s	1024 MB	Judgeable
Best SellerGiven each item's sales count and profit per sale, sort the items by total profit, then sales count, then name, and print each total.	Easy3	SortingImplementation	No attempts yet	1s	1024 MB	Judgeable
Why does this guy love 1122 so much?Given Q hints that a hidden integer in [-10^18, 10^18] is above or below some value, report whether the hints contradict, pin down the number, or leave it undetermined.	Easy3	ImplementationBinary search	No attempts yet	1.122s	1122 MB	Judgeable
Second NumbersGiven n, check whether its decimal digits can be split into two parts that are both primes without leading zeros.	Easy3	MathNumber theory+1	No attempts yet	2s	1024 MB	Judgeable
Color MixingEach operation adds one dye to a range of cans, and the task is to count the cans where exactly yellow and blue dyes were added.	Easy3	Prefix sumArray	No attempts yet	5s	1024 MB	Judgeable
T-ShirtsGiven n contestant scores and a minimum k, find the fewest shirts to hand out so that anyone scoring at least as much as a winner also gets one.	Easy3	SortingImplementation	No attempts yet	1s	1024 MB	Judgeable
ProgramsGiven program sizes and CD capacities, find the most programs that can each be matched to a different CD with enough capacity.	Easy3	GreedySorting+1	No attempts yet	12s	1024 MB	Judgeable
Albo psikus!Count the pairs (L, R) whose contiguous segment of candy counts has an even total, for N up to 1,000,000 houses.	Easy3	Prefix sumArray	No attempts yet	4s	1024 MB	Judgeable
BoardsGiven N board lengths, find the largest square area whose four equal sides can be cut from the boards by shortening them.	Easy3	SortingGreedy	No attempts yet	5s	1024 MB	Judgeable
WritersGiven text fragments from three Polish novels, output which author wrote each one: Mickiewicz, Prus, or Sienkiewicz.	Easy3	StringHash map	No attempts yet	10s	1024 MB	Judgeable
Uniform MakerGiven N words of equal length, find the total minimum number of character changes needed to make all words identical.	Easy3	GreedyString+1	No attempts yet	1s	1024 MB	Judgeable
BadstrandGiven plot prices along a coast and a budget B, find the longest contiguous run of plots whose total price is at most B.	Easy3	Sliding windowArray+1	No attempts yet	1s	1024 MB	Judgeable
Spotify ConnectGiven play and pause logs from a laptop and a phone, find the total milliseconds the laptop played, with phone commands delayed 100 ms.	Easy3	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Horse JumpingTwo horses on a grid move like chess knights and cannot land on stones. Determine whether their reachable cells overlap.	Easy3	BFSGraph+1	No attempts yet	6s	1024 MB	Judgeable
HostelGiven M bed types with a price and a stock limit each, find the cheapest way to book beds for N participants.	Easy3	GreedySorting	No attempts yet	1s	1024 MB	Judgeable
IP AddressesGiven a digit string, count the ways to insert three dots so that all four parts form valid IPv4 numbers in the 0 to 255 range without leading zeros.	Easy3	Brute forceString+1	No attempts yet	1s	1024 MB	Judgeable
Sorting the PlaylistCount the minimum number of adjacent swaps needed to sort N song lengths into ascending order.	Easy3	ArraySorting	No attempts yet	1s	1024 MB	Judgeable
RövarspråketGiven an original word and Oskar's word, decide whether encoding some consonants of the original as x-o-x can produce Oskar's word.	Easy3	StringTwo pointers	No attempts yet	1s	1024 MB	Judgeable
LimousineGiven grid positions and a time limit T, count how many contestants Simon can fetch and return to (0, 0), where each round trip costs twice the Manhattan distance.	Easy3	GreedySorting	No attempts yet	4s	1024 MB	Judgeable
The Bus CardGiven a travel amount K in SEK, find the fewest card top-ups of 100, 200, or 500 SEK that cover at least K.	Easy3	GreedyMath	No attempts yet	1s	1024 MB	Judgeable
Family ReunionGiven a family tree as a parent array, find the closest common ancestor of M seated people, which may be one of them.	Easy3	TreeImplementation	No attempts yet	1s	1024 MB	Judgeable
The GourmetCount the ordered sequences of dish times, chosen from the N given values, whose total eating time is exactly M minutes.	Easy3	Dynamic programming	No attempts yet	1s	1024 MB	Judgeable
Group DivisionGiven students and their friend pairs, find the largest number of groups where every friend pair stays together, which equals the count of friend clusters.	Easy3	Union-findGraph+1	No attempts yet	1s	1024 MB	Judgeable
TournamentGiven an even number of players n and a round number, print the pairs that play each other in that round of a rotating round robin schedule.	Easy3	ImplementationSimulation	No attempts yet	1s	1024 MB	Judgeable
LineupGiven how many taller children stand to each child's left and right, find the one lineup that matches all the slips for up to 8 children.	Easy3	BacktrackingBrute force	No attempts yet	1s	1024 MB	Judgeable
The Will Rogers PhenomenonGiven two groups of positive integers, find one number whose move to the other group raises the average of both groups, or report that none exists.	Easy3	Brute forceMath	No attempts yet	1s	1024 MB	Judgeable
ClockGiven the angle between the hour and minute hands in tenths of a degree, print the morning time that produces it as hh:mm.	Easy3	MathImplementation+1	No attempts yet	1s	1024 MB	Judgeable
PlankanCount the ordered ways to write a length n as a sum of parts 1, 2, and 3, where the order of boards matters.	Easy3	Dynamic programming	No attempts yet	1s	1024 MB	Judgeable
Cow CollegePick the tuition that maximizes price times the number of cows willing to pay it. Print the best revenue and the smallest such tuition.	Easy3	SortingGreedy	No attempts yet	2s	1024 MB	Judgeable
Cow PhrasebookCount how many of the N recorded messages are a prefix of at least one of the M phrases in the phrase book.	Easy3	Hash mapString	No attempts yet	1s	1024 MB	Judgeable
Alignment of the PlanetsGiven N grid points, list every triple of points that lie exactly on one line, with IDs sorted within each triple and across the output.	Easy3	GeometryBrute force+1	No attempts yet	1s	1024 MB	Judgeable
Satellite PhotographsGiven a W by H grid of pasture (*) and other (.) pixels, find the size of the largest group of horizontally or vertically connected pasture pixels.	Easy3	BFSMatrix	No attempts yet	1s	1024 MB	Judgeable
Max FactorGiven N distinct serial numbers up to 20,000, find the one whose largest prime factor is greatest, breaking ties by input order.	Easy3	Number theoryImplementation	No attempts yet	1s	1024 MB	Judgeable
Checking an AlibiFind the cows that can walk from their photographed field to the barn (field 1) within M seconds, using shortest path distances.	Easy3	Shortest pathGraph	No attempts yet	1s	1024 MB	Judgeable
Out of HayFind the smallest water capacity that lets Bessie reach every farm from Farm 1, which equals the largest edge in a minimum spanning tree.	Easy3	Minimum spanning treeUnion-find+2	No attempts yet	1s	1024 MB	Judgeable
Part AcquisitionGiven N one-way barter offers between K item types, find the fewest trades that turn item 1 into item K and list the trade order.	Easy3	BFSGraph+1	No attempts yet	1s	1024 MB	Judgeable
Feed AccountingGiven the feed bought, the amount left on day D, and each cow's stay, find the latest day the shipment could have arrived so exactly F2 kilograms remain on day D.	Easy3	SimulationPrefix sum	No attempts yet	1s	1024 MB	Judgeable
Bovine Ballroom DancingPair each boy cow with a girl cow so the total height difference is as small as possible, and print that minimum sum.	Easy3	SortingGreedy	No attempts yet	1s	1024 MB	Judgeable
The Middle SquaresRepeatedly square the middle two digits of a four-digit number and count the steps until a value repeats.	Easy3	SimulationHash map	No attempts yet	1s	1024 MB	Judgeable
LeapcowFind the fewest leaps of length 1 to L needed to go from 0 to E on a number line without landing on any of the buried cow positions.	Easy3	Dynamic programmingArray	No attempts yet	1s	1024 MB	Judgeable
Romeo Meets JulietFind the length of the longest run of consecutive fence gaps that holds at most C Cowpulets.	Easy3	Sliding windowArray	No attempts yet	1s	1024 MB	Judgeable
Bovine Math GeniusesRepeatedly squares the middle four digits of a six-digit value, keeps six digits, and reports the first repeated value, the loop length, and the iteration count.	Easy3	SimulationHash map	No attempts yet	1s	16 MB	Judgeable
Strolling CowsGiven N pastures where each pasture has exactly one outgoing path, find the number of pastures in the longest cycle that returns to its start without repeats.	Easy3	GraphTopological sort	No attempts yet	1s	1024 MB	Judgeable
Round of 16 and QueriesGiven each team's standings and the goals in the last two matches, the task is to report after each goal whether Korea advances to the Round of 16.	Easy3	SimulationImplementation	No attempts yet	1s	512 MB	Judgeable
Wiggle NumbersGiven a positive integer of up to 75 digits and a power P from 1 to 5, find how many terms pass before the sum-of-digit-powers sequence enters its cycle.	Easy3	SimulationHash map	No attempts yet	1s	1024 MB	Judgeable
Extra KrunchGiven one line of capital letters, blanks, and punctuation, remove vowels, repeated letters, and extra blanks, then print the krunched line.	Easy3	StringHash map+1	No attempts yet	1s	1024 MB	Judgeable
TrappedCount the cells of an ASCII maze from which the single exit on the right side of row 1 cannot be reached.	Easy3	BFSGraph	No attempts yet	1s	1024 MB	Judgeable
Metric MatricesGiven an N by N distance matrix, check the four metric axioms and print the smallest number of any axiom it violates, or 0 if it is a metric.	Easy3	Brute forceMatrix+1	No attempts yet	1s	1024 MB	Judgeable
Spinning WheelsFind the earliest integer second when wedges on all five spinning wheels line up so a beam passes through, or report none.	Easy3	Brute forceSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Entry RecordsGiven today's ordered entry and exit records, find the fewest records that must be missing so each person's enter and leave events alternate correctly.	Easy3	Hash mapImplementation	No attempts yet	1s	1024 MB	Judgeable
Bessie Come HomeGiven pastures connected by weighted paths, find the cow (capital letter pasture) with the shortest distance to barn Z and print its name and distance.	Easy3	Shortest pathGraph	No attempts yet	1s	1024 MB	Judgeable
Agri-NetGiven an N by N distance matrix of farms, find the total length of the cheapest set of connections that links all farms together.	Easy3	Minimum spanning treeGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Unique QuotientsAssign distinct digits to A through J so that the five-digit number ABCDE equals 9 times FGHIJ, and output the Nth solution by ABCDE.	Easy3	Brute forceImplementation	No attempts yet	1s	1024 MB	Judgeable
ChecksRead a dollar amount under one trillion with two decimal places and print it in check-style English words, with AND before the cents.	Easy3	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
Long MultiplicationGiven two positive integers of up to 20 digits, print their long multiplication in the vertical layout, with each partial product and the final sum aligned.	Easy3	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
The Tamworth TwoSimulate a cow pair and Farmer John on a 10 by 10 grid, both turning clockwise at walls, and report the first minute they share a square.	Easy3	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Cows in BedFind the smallest K such that the N brand numbers all have distinct remainders when divided by K.	Easy3	Brute forceHash map	No attempts yet	1s	1024 MB	Judgeable
Sum25Count the subsets of 7 given digits whose sum is 25, where each digit 0 counts as 10.	Easy3	Brute forceBacktracking	No attempts yet	1s	1024 MB	Judgeable
Cows in BedGiven N brand numbers, find the smallest K such that all brands taken mod K are distinct.	Easy3	Brute forceHash map+1	No attempts yet	1s	1024 MB	Judgeable
Highest MountainGiven a grid of heights, find the largest max-minus-min height difference among connected groups of two or more mountainous cells, or -1 if none exist.	Easy3	MatrixBFS+1	No attempts yet	1s	1024 MB	Judgeable
Negative Number BasesConvert the integer N to base B (negative bases allowed, from -10 to -2 and 2 to 10) and print its digits with no sign.	Easy3	MathSimulation	No attempts yet	1s	1024 MB	Judgeable
Crazy TimeGiven the order of flipped cards, output the time each turn must be called and whether players slap, under the reverse and sync rules.	Easy3	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Shrine for the GodsGiven statues facing left (1) or right (2), find the largest absolute difference between left and right counts over any contiguous segment.	Easy3	Prefix sumArray	No attempts yet	2s	512 MB	Judgeable
Dissimilar numbersGiven x and a range [l, r] of at most 1001 values, list every y in the range that differs from x and has gcd with x equal to 1 or a prime.	Easy3	MathBrute force	No attempts yet	1s	1024 MB	Judgeable
Multiple SegmentsCount the contiguous segments of an array of natural numbers whose sum is divisible by k.	Easy3	Prefix sumHash map+1	No attempts yet	1s	1024 MB	Judgeable
ClassGiven n boys and m girls seated two per desk, find the maximum number of students who sit alone or with a student of the other gender.	Easy3	MathGreedy	No attempts yet	1s	1024 MB	Judgeable
Against Bertrand's PostulateGiven n, find the longest run of consecutive composite numbers strictly between n and 2n, and output its endpoints l and r.	Easy3	SortingMath+2	No attempts yet	1s	1024 MB	Judgeable
Distinct SquaresGiven n unit squares, find the maximum number of distinct squares that can be built, where a square with side k uses k^2 units.	Easy3	MathBinary search	No attempts yet	1s	1024 MB	Judgeable
SpiralThe task simulates a robot that draws a spiral with growing step lengths, then prints the bounding box of visited cells with stars and dots.	Easy3	SimulationImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Two GiftsGiven n gift prices and a budget x, find the largest sum of two different gifts that does not exceed x.	Easy3	Two pointersSorting	No attempts yet	1s	1024 MB	Judgeable
FramesDraw n rectangle borders on an h by w grid in input order, marking the i-th frame with the i-th letter, and print the final picture.	Easy3	ImplementationSimulation	No attempts yet	1s	1024 MB	Judgeable
Interesting PartitionsGiven n, list every partition of n into summands that are all distinct and where no two summands differ by exactly 1.	Easy3	BacktrackingRecursion	No attempts yet	1s	1024 MB	Judgeable