Problems

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Total results29,475 problems

Poker Card Combinations
Easy3
Hash map, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Davor's Travel Fund
Easy3
Brute force, Math+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Xayahh-Rakann at Moloco (Easy)
Easy3
Brute force, Graph+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
League of Overwatch at Moloco (Easy)
Easy3
Graph, BFS
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Äventyr 1
Easy3
Array, Sorting+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Blocked Billboard II
Easy3
Geometry, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Lifeguards
Easy3
Intervals, Brute force+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Accepted ratio
Easy3
Implementation, Hash map+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
IDN Homograph Attack
Easy3
String, Hash map+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Going Down 2
Easy3
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
N and M (1)
Easy3
Backtracking, Recursion
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
N and M (2)
Easy3
Backtracking, Recursion+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
N and M (3)
Easy3
Backtracking, Recursion+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
N and M (4)
Easy3
Backtracking, Recursion
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Length M sequences from N numbers
Easy3
Backtracking, Recursion+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
N and M (6)
Easy3
Backtracking, Sorting+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
N and M (10)
Easy3
Backtracking, Sorting+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
2018 Yonsei University Programming Contest
Easy3
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Trees and Queries
Easy3
Tree, DFS+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sorting numbers 5
Easy3
Sorting, Array+1
No attempts yet
Time limit
10s
Memory limit
128 MB
Judgeable
Tile Filling 4
Easy3
Math, Greedy+1
No attempts yet
Time limit
0.1s
Memory limit
512 MB
Judgeable
Ordered Pairs
Easy3
Math, Number theory+2
No attempts yet
Time limit
0.5s
Memory limit
512 MB
Judgeable
Duplicated number
Easy3
Math
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Beondegi
Easy3
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Round and Round Snail
Easy3
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Multiply and Divide
Easy3
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Blue Flag, White Flag
Easy3
Math, Number theory+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Team Tic Tac Toe
Easy3
Brute force, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Are the power strips enough?
Easy3
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Send me the money
Easy3
String, Two pointers+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Sejin's Group Date
Easy3
Combinatorics, Math+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
A/B to 2000 decimal places
Easy3
Math, Implementation+1
No attempts yet
Time limit
0.5s
Memory limit
512 MB
Judgeable
Router
Easy3
Queue, Simulation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Explorace
Easy3
Minimum spanning tree, Graph+2
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Sum of Subrectangle Areas
Easy3
Math, Combinatorics
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Stroop Effect
Easy3
Implementation, Simulation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Virus Outbreak
Easy3
Math, Dynamic programming+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Ninety-nine
Easy3
Game theory, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
A+B Without Spaces
Easy3
String, Brute force+1
No attempts yet
Time limit
0.5s
Memory limit
512 MB
Judgeable
The Answer Is Isugeun!
Easy3
Math, Number theory+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Grenade in the Lake!!
Easy3
Greedy, Intervals+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Math Is PE
Easy3
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Badly implemented sieve of Eratosthenes
Easy3
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Stella Gives Chicken Gifts
Easy3
Sorting, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Yet Another No-Solve Prevention Problem!!
Easy3
Bit manipulation, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Ukje Is the Architecture King!!
Easy3
Geometry, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
A Palindrome Is Not a Palindrome!!
Easy3
String, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Baby Sukhwan Tururu Turu
Easy3
Implementation, Math+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Kth Prime Number
Easy3
Number theory, Math+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Finding the Modular Inverse
Easy3
Number theory, Math+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Factorial
Easy3
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Plug It In!
Easy3
Graph, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
The Devil's Temptation
Easy3
Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Binary Search Tree
Easy3
Tree, Recursion+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Twenty Thousand Leagues Under the Sea
Easy3
Array, Brute force+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Tide Pods
Easy3
Array, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Girl Group Master Junseok
Easy3
Hash map, Sorting+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
I Have Few Friends (Small)
Easy3
String, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Jelly Jump (Large)
Easy3
Dynamic programming, Matrix+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
New House
Easy3
Matrix, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Buying Cards 2
Easy3
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Calculating Ages
Easy3
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Variable Names
Easy3
String, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Nadan
Easy3
Greedy, Math+2
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Spreadsheets
Easy3
Math, String+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Farm
Easy3
Math, Implementation
No attempts yet
Time limit
0.1s
Memory limit
512 MB
Judgeable
Appalling Architecture
Easy3
Array, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Go Latin
Easy3
String, Implementation
No attempts yet
Time limit
0.5s
Memory limit
512 MB
Judgeable
Treehouses
Easy3
Minimum spanning tree, Union-find+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Exam
Easy3
String, Greedy+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Heir's Dilemma
Easy3
Brute force, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
The Rice Cake Seller and the Tiger
Easy3
Dynamic programming, Backtracking+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Enigma
Easy3
String, Brute force+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Season of Reading
Easy3
String, Recursion+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Cupid
Easy3
Sorting, Implementation
No attempts yet
Time limit
1.004s
Memory limit
512 MB
Judgeable
Professor Na's Bad Handwriting
Easy3
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Concert
Easy3
Sorting, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
A Homogeneous Country
Easy3
Hash map, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Measuring the Height of a Cup Noodle
Easy3
Math, Geometry
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Let's Construct! - ②
Easy3
Math, Geometry+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
One Lap Around the Playground
Easy3
Math, Geometry+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Grouping Identical Words
Easy3
Sorting, Hash map+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Paper Folding
Easy3
Array, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Star
Easy3
Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Predictable Queue
Easy3
Prefix sum, Binary search
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Potato Sacks
Easy3
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Alpha Tic-Tac-Toe
Easy3
Game theory, Recursion+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Lie Detector
Easy3
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Aligned Typesetting
Easy3
String, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Froggie
Easy3
Simulation, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Looking Back on 2018
Easy3
Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Two Hands
Easy3
Brute force, Implementation
No attempts yet
Time limit
0.1s
Memory limit
128 MB
Judgeable
Multinomial Coefficient
Easy3
Dynamic programming, Combinatorics
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
ICPC
Easy3
Implementation, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Chaarshanbegaan at Cafebazaar
Easy3
Math, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Congestion Charging Zone
Easy3
Implementation, Sorting
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Turnarounds
Easy3
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Social Game
Easy3
Math, Greedy+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Sugoroku and Pieces
Easy3
Simulation, Array+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Thread Tree
Easy3
Tree, DFS+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Poker Card CombinationsGiven six card ranks, count how often each rank appears and print which of the nine named poker combinations the hand forms.	Easy3	Hash mapImplementation+1	No attempts yet	1s	512 MB	Judgeable
Davor's Travel FundFind X and K so that 52 weeks of daily deposits, rising by K each day from Monday, total exactly N, maximizing X first and minimizing K.	Easy3	Brute forceMath+1	No attempts yet	1s	64 MB	Judgeable
Xayahh-Rakann at Moloco (Easy)Given n jars and inseparable pairs, decide if exactly k jars can be kept so that no inseparable pair is split across the two groups.	Easy3	Brute forceGraph+1	No attempts yet	2s	512 MB	Judgeable
League of Overwatch at Moloco (Easy)Given a conflict graph, decide whether the vertices can be split into two non-empty groups so every conflicting pair is separated.	Easy3	GraphBFS	No attempts yet	2s	512 MB	Judgeable
Äventyr 1On a path 1 to N, vertices become active over time; after each activation, answer the distance from a query vertex to the nearest active vertex, or -1 if none exists yet.	Easy3	ArraySorting+2	No attempts yet	1s	256 MB	Judgeable
Blocked Billboard IIGiven two axis-aligned rectangles, find the smallest rectangle that covers the first billboard minus the part hidden by the second.	Easy3	GeometryImplementation+2	No attempts yet	2s	512 MB	Judgeable
LifeguardsGiven N shifts, remove exactly one so that the total time covered by the remaining shifts is maximized.	Easy3	IntervalsBrute force+1	No attempts yet	2s	512 MB	Judgeable
Accepted ratioGiven a submission log, ignore the administrator, count solvers and the rejections each made before their first accepted submission, then print the accepted ratio with 10 decimals.	Easy3	ImplementationHash map+2	No attempts yet	2s	512 MB	Judgeable
IDN Homograph AttackGiven a string, decide whether some character can be swapped for a different character that normalizes to the same form.	Easy3	StringHash map+2	No attempts yet	1s	256 MB	Judgeable
Going Down 2Given N rows of three digits, move down choosing reachable cells and report the maximum and minimum possible sum of the digits passed through.	Easy3	Dynamic programmingArray	No attempts yet	1s	512 MB	Judgeable
N and M (1)Print every length-M sequence of distinct numbers chosen from 1 to N, in increasing lexicographic order.	Easy3	BacktrackingRecursion	No attempts yet	1s	512 MB	Judgeable
N and M (2)Print all ascending sequences of M distinct numbers chosen from 1 to N, in lexicographic order.	Easy3	BacktrackingRecursion+1	No attempts yet	1s	512 MB	Judgeable
N and M (3)Print every length-M sequence from 1 to N in lexicographic order, allowing repeats.	Easy3	BacktrackingRecursion+2	No attempts yet	1s	512 MB	Judgeable
N and M (4)Print all non-decreasing sequences of length M chosen from 1 to N, each exactly once, in lexicographic order.	Easy3	BacktrackingRecursion	No attempts yet	1s	512 MB	Judgeable
Length M sequences from N numbersGiven N distinct numbers and an M, print every length-M permutation of the numbers in lexicographic order without repeats.	Easy3	BacktrackingRecursion+2	No attempts yet	1s	512 MB	Judgeable
N and M (6)Given N distinct natural numbers and M, print every ascending M-element subsequence in lexicographic order without repeats.	Easy3	BacktrackingSorting+2	No attempts yet	1s	512 MB	Judgeable
N and M (10)Given N numbers and an M, print every non-decreasing length-M selection of the numbers in lexicographic order without duplicates.	Easy3	BacktrackingSorting+2	No attempts yet	1s	512 MB	Judgeable
2018 Yonsei University Programming ContestGiven the total spark count N of a firework that bursts once then bursts again, find the branching factor K.	Easy3	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Trees and QueriesCount the vertices in the subtree of each queried node in a tree with a given root.	Easy3	TreeDFS+1	No attempts yet	1s	128 MB	Judgeable
Sorting numbers 5Read up to a million integers and print them in non-decreasing order, one per line.	Easy3	SortingArray+1	No attempts yet	10s	128 MB	Judgeable
Tile Filling 4Find the maximum number of 2x1 and 1x2 dominoes that fit on an N by M wall without overlap.	Easy3	MathGreedy+1	No attempts yet	0.1s	512 MB	Judgeable
Ordered PairsCount the ordered pairs of natural numbers whose product equals a given N.	Easy3	MathNumber theory+2	No attempts yet	0.5s	512 MB	Judgeable
Duplicated numberA size-N array contains 1..N-1 with one value M repeated; find M.	Easy3	Math	No attempts yet	2s	256 MB	Judgeable
BeondegiGiven A players in a circle and a chant pattern by rounds, find who makes the T-th call of a chosen word (ppeon or degi), counting only that word.	Easy3	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Round and Round SnailA snail walks a clockwise square spiral from the origin, one cell per second; given n seconds, print its coordinates.	Easy3	ImplementationSimulation+2	No attempts yet	1s	128 MB	Judgeable
Multiply and DivideGiven three integers in fixed order, insert one multiplication and one division sign to maximize the value, evaluated left to right.	Easy3	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Blue Flag, White FlagEach of N players flips every flag whose number is a multiple of their index; count how many flags end white side up.	Easy3	MathNumber theory+2	No attempts yet	1s	128 MB	Judgeable
Team Tic Tac ToeGiven a filled 3x3 board of letters, count single cows that own a full line and two-cow teams that together own a line with both letters present.	Easy3	Brute forceImplementation+2	No attempts yet	2s	512 MB	Judgeable
Are the power strips enough?Given K power strips with 3 to 8 sockets each, each strip can power at most half its sockets since adjacent sockets cannot both be used; decide if the total reaches N.	Easy3	GreedyMath+1	No attempts yet	1s	512 MB	Judgeable
Send me the moneyGiven a pattern string S, decide for each of M notes whether S is a subsequence of the note.	Easy3	StringTwo pointers+2	No attempts yet	1s	512 MB	Judgeable
Sejin's Group DateGiven N men and M women (M <= N), count the number of M-element subsets of men that could be paired with the women, modulo 1000000007.	Easy3	CombinatoricsMath+2	No attempts yet	1s	512 MB	Judgeable
A/B to 2000 decimal placesPrint A/B with exactly 2000 digits after the decimal point, truncating rather than rounding.	Easy3	MathImplementation+1	No attempts yet	0.5s	512 MB	Judgeable
RouterSimulate a buffer of size N: packets arrive in order, 0 means one is handled and removed from the front, and a packet arriving with the buffer full is dropped.	Easy3	QueueSimulation+2	No attempts yet	1s	512 MB	Judgeable
ExploraceGiven a weighted undirected graph of checkpoints, find the minimum total length of edges that keeps every checkpoint connected.	Easy3	Minimum spanning treeGraph+2	No attempts yet	3s	512 MB	Judgeable
Sum of Subrectangle AreasFor each N, compute the total area of all axis-aligned integer subrectangles in an N by N grid.	Easy3	MathCombinatorics	No attempts yet	2s	512 MB	Judgeable
Stroop EffectGiven sequences of two-digit word-ink codes, check whether each sequence satisfies the counts and the no-three-in-a-row rule for a valid Stroop test.	Easy3	ImplementationSimulation+2	No attempts yet	2s	512 MB	Judgeable
Virus OutbreakRead hour values until -1 and print the Fibonacci number a(X) for each in the format 'Hour X: Y cow(s) affected'.	Easy3	MathDynamic programming+2	No attempts yet	2s	512 MB	Judgeable
Ninety-nineTwo players take turns adding 1 or 2 to a running count that starts at 1 or 2, and the task is to write a program that picks the start and moves so you say 99 first.	Easy3	Game theoryMath	No attempts yet	1s	1024 MB	Judgeable
A+B Without SpacesA string holds two numbers from 1 to 10 with no separator; find a split that makes two valid natural numbers and print their sum.	Easy3	StringBrute force+1	No attempts yet	0.5s	512 MB	Judgeable
The Answer Is Isugeun!Given integer coefficients A, B, C, classify the roots of Ax^2 + Bx + C = 0 as powers of two, integer roots, or neither.	Easy3	MathNumber theory+2	No attempts yet	2s	256 MB	Judgeable
Grenade in the Lake!!Given people on a line with throw ranges, decide whether the grenade can travel from the first person to the last.	Easy3	GreedyIntervals+1	No attempts yet	2s	512 MB	Judgeable
Math Is PEThe bottom row of a staircase of 1x1 squares has n squares; output the perimeter shown by the solid line.	Easy3	MathImplementation	No attempts yet	1s	512 MB	Judgeable
Badly implemented sieve of EratosthenesCount how many times the inner statement runs in a nested loop where the outer index i goes from 1 to n and the inner step is i, for n up to 10^9.	Easy3	MathNumber theory+1	No attempts yet	1s	512 MB	Judgeable
Stella Gives Chicken GiftsRank participants by solved count, then penalty, and count how many solved as many problems as the fifth place but finished below it.	Easy3	SortingImplementation	No attempts yet	2s	512 MB	Judgeable
Yet Another No-Solve Prevention Problem!!For each of Q queries, decide whether the given number a is a power of two, printing 1 for yes and 0 for no.	Easy3	Bit manipulationMath+2	No attempts yet	2s	512 MB	Judgeable
Ukje Is the Architecture King!!Given the vertices of an axis-aligned orthogonally convex polygon in order, output its perimeter.	Easy3	GeometryImplementation+1	No attempts yet	2s	512 MB	Judgeable
A Palindrome Is Not a Palindrome!!Given an uppercase string up to 500,000 characters, find the length of the longest substring that is not a palindrome, or -1 if none exists.	Easy3	StringImplementation+2	No attempts yet	2s	512 MB	Judgeable
Baby Sukhwan Tururu TuruFind the N-th word of a repeating song whose tururu runs grow by one extra ru each repetition, with long runs printed in a compressed form.	Easy3	ImplementationMath+2	No attempts yet	1s	512 MB	Judgeable
Kth Prime NumberGiven K up to 500,000, print the K-th prime number.	Easy3	Number theoryMath+1	No attempts yet	2s	256 MB	Judgeable
Finding the Modular InverseGiven coprime positive integers a and m, find the smallest positive x with a*x congruent to 1 modulo m.	Easy3	Number theoryMath+2	No attempts yet	1s	512 MB	Judgeable
FactorialGiven N and a prime A, find the largest k such that A^k divides N! (the exponent of A in the prime factorization of N!).	Easy3	Number theoryMath+1	No attempts yet	1s	512 MB	Judgeable
Plug It In!Given socket-to-device connections, count how many devices can be powered when plugbars can triple a socket any number of times.	Easy3	GraphImplementation	No attempts yet	2s	512 MB	Judgeable
The Devil's TemptationSubmit to this problem and you are locked out of every remaining problem for exactly 31,557,600 seconds, a fixed one-year waiting period.	Easy3	Implementation	No attempts yet	1s	512 MB	Judgeable
Binary Search TreeInsert a sequence of integers into a BST and output the depth of each inserted node.	Easy3	TreeRecursion+1	No attempts yet	2s	512 MB	Judgeable
Twenty Thousand Leagues Under the SeaAmong N cages with given hole sizes, pick the largest hole whose area is under M and report its input index, or output Too small.	Easy3	ArrayBrute force+1	No attempts yet	2s	512 MB	Judgeable
Tide PodsScore each model person by the number of shared traits times their score, then output the largest minus smallest score. Multiple data sets follow, and each result gets its own header and trailing blank line.	Easy3	ArrayImplementation	No attempts yet	2s	512 MB	Judgeable
Girl Group Master JunseokRead N girl groups with member lists, then answer M quizzes: list a team's members sorted, or name a member's team.	Easy3	Hash mapSorting+1	No attempts yet	2s	128 MB	Judgeable
I Have Few Friends (Small)A textbook text S may contain digits that stand for unknown letters. Decide whether a keyword K (letters only) can match some substring of S, treating each digit as any letter.	Easy3	StringBrute force+1	No attempts yet	1s	128 MB	Judgeable
Jelly Jump (Large)Given an N by N board where each cell holds a jump length, decide whether Jelly can travel from the top-left cell to the bottom-right cell moving only right or down.	Easy3	Dynamic programmingMatrix+2	No attempts yet	2s	128 MB	Judgeable
New HouseGiven an N by N grid of free cells and obstacles, find the side length of the largest square made only of free cells.	Easy3	MatrixDynamic programming+1	No attempts yet	2s	512 MB	Judgeable
Buying Cards 2Given prices for card packs of sizes 1 to N, find the cheapest way to buy packs whose card counts sum to exactly N.	Easy3	Dynamic programming	No attempts yet	1s	256 MB	Judgeable
Calculating AgesGiven a birth date and a reference date, compute the person's full, counting, and year ages on the reference date.	Easy3	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Variable NamesGiven a variable name in camel, snake, or Pascal case, print its camel, snake, and Pascal forms.	Easy3	StringImplementation	No attempts yet	2s	512 MB	Judgeable
NadanSplit K into N distinct positive integers that sum to K, and print one such distribution.	Easy3	GreedyMath+2	No attempts yet	1s	64 MB	Judgeable
SpreadsheetsConvert a column index up to 1e9 into a base-26 name like A, Z, AA, using letters with no zero digit.	Easy3	MathString+2	No attempts yet	2s	512 MB	Judgeable
FarmGiven feed rates a and b, animal count n, and total feed w, find the sheep and goat counts, or print -1 if the answer is missing or not unique.	Easy3	MathImplementation	No attempts yet	0.1s	512 MB	Judgeable
Appalling ArchitectureGiven a grid of filled 1x1 boxes forming one grounded component, compare the center of gravity's x-coordinate with the leftmost and rightmost ground-contact x to say left, balanced, or right.	Easy3	ArrayMath+1	No attempts yet	1s	512 MB	Judgeable
Go LatinTranslate each English word to pseudo-Latin by replacing the suffix per a table, or appending "us" when no listed suffix matches.	Easy3	StringImplementation	No attempts yet	0.5s	512 MB	Judgeable
TreehousesConnect all treehouse points plus the first e ground access points by cables of minimum total length, given some cables already exist; output the added length as a MST problem.	Easy3	Minimum spanning treeUnion-find+2	No attempts yet	2s	512 MB	Judgeable
ExamGiven two answer strings and how many answers your friend got right, maximize your own possible score over all valid answer keys.	Easy3	StringGreedy+1	No attempts yet	2s	512 MB	Judgeable
Heir's DilemmaCount six-digit numbers between L and H whose digits are nonzero and distinct and that are divisible by each of their own digits.	Easy3	Brute forceMath+1	No attempts yet	2s	512 MB	Judgeable
The Rice Cake Seller and the TigerPick one rice cake kind from each day's set so consecutive picks differ; output the daily picks or -1 if impossible.	Easy3	Dynamic programmingBacktracking+1	No attempts yet	1s	128 MB	Judgeable
EnigmaCount alignments of the crib inside the ciphertext where no crib letter equals the ciphertext letter at the same offset.	Easy3	StringBrute force+1	No attempts yet	2s	512 MB	Judgeable
Season of ReadingReplace WHO, WHERE, and WHAT in each sentence with the given resolving elements, expanding nested references.	Easy3	StringRecursion+1	No attempts yet	1s	512 MB	Judgeable
CupidFilter N users by gender preference and distance limit, sort the matching names lexicographically, and print them or "No one yet".	Easy3	SortingImplementation	No attempts yet	1.004s	512 MB	Judgeable
Professor Na's Bad HandwritingReplace every 0 and 6 digit with 9 in each score, cap at 100, then print the integer nearest the average, breaking ties upward.	Easy3	ImplementationMath+1	No attempts yet	1s	512 MB	Judgeable
ConcertGiven up to one million first-round ticket numbers, find the smallest positive integer not among them.	Easy3	SortingImplementation	No attempts yet	1s	512 MB	Judgeable
A Homogeneous CountryCount class label frequencies over up to 100,000 lines and compute 1 minus the sum of squared relative frequencies.	Easy3	Hash mapMath	No attempts yet	1s	256 MB	Judgeable
Measuring the Height of a Cup NoodleGiven two parallel base diameters D1, D2 and the slanted side K of an isosceles trapezoid, compute the squared height.	Easy3	MathGeometry	No attempts yet	1s	512 MB	Judgeable
Let's Construct! - ②Given side lengths c of AB and b of AC, compute the ratio in which the internal angle bisector of angle A divides side BC.	Easy3	MathGeometry+1	No attempts yet	1s	512 MB	Judgeable
One Lap Around the PlaygroundCompute the perimeter of a track made of a rectangle between two semicircles, given the rectangle width and one semicircle radius, using pi = 3.141592.	Easy3	MathGeometry+1	No attempts yet	1s	512 MB	Judgeable
Grouping Identical WordsCount words that are permutations of each other using letter counts, and print the number of distinct letter multisets.	Easy3	SortingHash map+1	No attempts yet	2s	512 MB	Judgeable
Paper FoldingGiven an N by N grid of numbers (N is a power of two), fold the paper in half repeatedly adding overlapping cells until one number remains; print it.	Easy3	ArrayMath+1	No attempts yet	1s	512 MB	Judgeable
StarPrint a star pattern whose exact rule is inferred from sample outputs, with no trailing spaces on any line.	Easy3	Implementation	No attempts yet	1s	512 MB	Judgeable
Predictable QueueGiven N task times and M time limits T, print how many tasks are processed first in order before their prefix sum exceeds T.	Easy3	Prefix sumBinary search	No attempts yet	1s	512 MB	Judgeable
Potato SacksGiven ten potato weights and a capacity C, decide whether some subset of the potatoes sums to exactly C and print YES or NO.	Easy3	Dynamic programmingBit manipulation+1	No attempts yet	2s	512 MB	Judgeable
Alpha Tic-Tac-ToeGiven a 3x3 tic-tac-toe board with X to move or O to move, find whether the side to move can force a win, a draw, or only a loss under perfect play.	Easy3	Game theoryRecursion+1	No attempts yet	1s	256 MB	Judgeable
Lie DetectorEach detector vouches for the previous one except the last, which is always right. Walk the chain backwards and flip the answer once per LIE report.	Easy3	ImplementationSimulation	No attempts yet	1s	512 MB	Judgeable
Aligned TypesettingGiven an equal number of spaces between every pair of consecutive words, decide whether one such aligned typesetting has total length exactly L.	Easy3	StringMath+1	No attempts yet	2s	512 MB	Judgeable
FroggieSimulate Froggie hopping across lanes of evenly spaced moving cars on a grid and report whether she exits the top lane safely or gets squished.	Easy3	SimulationImplementation	No attempts yet	2s	512 MB	Judgeable
Looking Back on 2018Given N up to 1e9, classify it as 0, 1, 2, or 8 based on which digits from 2, 0, 1, 8 appear and whether their counts are equal.	Easy3	Implementation	No attempts yet	1s	256 MB	Judgeable
Two HandsGiven two players' left and right hand gestures, determine which player can guarantee a win with a well-chosen hand, or output '?' if neither can force a win.	Easy3	Brute forceImplementation	No attempts yet	0.1s	128 MB	Judgeable
Multinomial CoefficientGiven exponents n and m and a power k, compute the coefficient of x^k in (1+x+...+x^n)^m modulo 1,000,000,009.	Easy3	Dynamic programmingCombinatorics	No attempts yet	2s	256 MB	Judgeable
ICPCGiven the four goal counts from two-legged finals, apply aggregate scores and the away goals tiebreak to name the winner or output Penalty.	Easy3	ImplementationMath+1	No attempts yet	2s	512 MB	Judgeable
Chaarshanbegaan at CafebazaarGiven up to 100 dart coordinates, score each by its distance from the board center and print the total score.	Easy3	MathImplementation+1	No attempts yet	2s	512 MB	Judgeable
Congestion Charging ZoneGiven up to 100 camera sighting times for one vehicle, find its first and last times in 6:30 to 19:00 and output the matching charge from the table.	Easy3	ImplementationSorting	No attempts yet	2s	512 MB	Judgeable
TurnaroundsGiven the seconds when each team scored, report how many points fell in the first half and how many times the lead changed from strictly behind to strictly ahead.	Easy3	ImplementationSimulation+2	No attempts yet	1s	512 MB	Judgeable
Social GameGiven A, B, C, find the fewest logins that yield at least C coins, counting A per login plus B per full Mon-to-Sun week.	Easy3	MathGreedy+2	No attempts yet	2s	512 MB	Judgeable
Sugoroku and PiecesMove pieces forward one square on a 2019-square board, but block moves onto the goal or an occupied square, then report each piece's final position.	Easy3	SimulationArray+1	No attempts yet	2s	512 MB	Judgeable
Thread TreeGiven n posts where each post names its parent post, print the messages in preorder with dots showing each post's depth.	Easy3	TreeDFS+1	No attempts yet	2s	512 MB	Judgeable