Problems

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Total results29,473 problems

Retype
Easy3
Math, Implementation+1
No attempts yet
Time limit
20s
Memory limit
1024 MB
Judgeable
ZOAC 4
Easy3
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Common Anagrams
Easy3
Hash map, String+2
No attempts yet
Time limit
20s
Memory limit
1024 MB
Judgeable
Zathras
Easy3
Simulation, Implementation+2
No attempts yet
Time limit
20s
Memory limit
1024 MB
Judgeable
Impartial Offerings
Easy3
Sorting, Greedy+2
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Garden (Easy)
Easy3
Dynamic programming, Simulation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Rare Number
Easy3
Hash map, Array+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Contest
Easy3
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Score
Easy3
Sorting, Array+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Fiber Optic Network (Fiber)
Easy3
Union-find, Graph+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tokyo2020
Easy3
Implementation, Hash map+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Rabbit Hole
Easy3
Simulation, Brute force+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Mind Reading
Easy3
Math, Implementation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Chopsticks
Easy3
Math, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
What makes 2022 special?
Easy3
Math, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Garden
Easy3
Math, Implementation
No attempts yet
Time limit
0.1s
Memory limit
1024 MB
Judgeable
Book Covers
Easy3
Implementation, Math+1
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Guess the digit
Easy3
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
РАВЕНСТВО
Easy3
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Painting the Fence
Easy3
Intervals, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
ДИНИ
Easy3
Brute force, Array+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Algorithm Class - Asymptotic Notation 2
Easy3
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Algorithm Class - Asymptotic Notation 3
Easy3
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Two Albums
Easy3
Sorting, Hash map+2
No attempts yet
Time limit
0.4s
Memory limit
1024 MB
Judgeable
Special
Easy3
Sliding window, String+2
No attempts yet
Time limit
0.4s
Memory limit
1024 MB
Judgeable
ИЗРАЗ
Easy3
Brute force, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Elevator
Easy3
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Game
Easy3
Array, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Distinct lengths of runs of zeros
Easy3
String, Simulation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
СПОРТ
Easy3
Backtracking, Recursion+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Honey Exhibition
Easy3
Brute force, Greedy+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Two's Complement
Easy3
Bit manipulation, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Microwave Again?
Easy3
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Yeongjae's Stepping Stones
Easy3
Dynamic programming, Matrix
No attempts yet
Time limit
0.5s
Memory limit
512 MB
Judgeable
Finding the Joker
Easy3
Simulation, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Mult!
Easy3
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Algorithm Class - Fibonacci Number 2
Easy3
Math, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Algorithm Class - Matrix Path Problem 1
Easy3
Dynamic programming, Recursion+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Multiplication
Easy3
Brute force, Array+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Algorithm Class - Breadth-First Search 3
Easy3
Graph, BFS+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Encryption Matrix
Easy3
Matrix, Brute force+1
No attempts yet
Time limit
0.8s
Memory limit
512 MB
Judgeable
Algorithm Class - Depth-First Search 3
Easy3
DFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Herdle
Easy3
Implementation, Array+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Blob's Apple Pies
Easy3
Array, Sliding window+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Next Different Number
Easy3
Array, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Good Fours and Good Fives
Easy3
Math, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Code Guessing
Easy3
Brute force, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Stream Lag
Easy3
Simulation, Greedy+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Overdraft
Easy3
Prefix sum, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Who Goes There?
Easy3
Simulation, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fences
Easy3
Geometry, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Follow the Trace!
Easy3
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Anno Domini 2022
Easy3
Implementation, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Letters Q and F
Easy3
Implementation, Matrix
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Kemija
Easy3
String, Hash map
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Parts Management with Hyundai Mobis
Easy3
Implementation, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
MBTI
Easy3
Matrix, String matching+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sequinary Numerals
Easy3
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
CIDR
Easy3
Bit manipulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Morse Code Palindromes
Easy3
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Letterle
Easy3
Implementation, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Social Distancing
Easy3
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ticket Completed?
Easy3
Union-find, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Wordle with Friends
Easy3
Simulation, String+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Beekeeper
Easy3
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Un-bear-able Zoo
Easy3
Hash map, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ornaments
Easy3
Math, Geometry
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Recount
Easy3
Hash map, String
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Set!
Easy3
Brute force, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Linden Mayor System
Easy3
String, Simulation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Cracking RSA
Easy3
Math, Number theory+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Cookie Cutters
Easy3
Geometry, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Railroad
Easy3
Math, Graph
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Shiritori
Easy3
String, Hash map
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
The weight of words
Easy3
Dynamic programming, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Coconut Splat
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Touchdown!
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Grand Adventure
Easy3
Stack, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Competitive Arcade Basketball
Easy3
Hash map, Simulation
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Escape Wall Maria
Easy3
BFS, Matrix
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Spelling Bee
Easy3
String, Implementation
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Musical Trees
Easy3
Greedy, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Speed Typing
Easy3
String, Two pointers+1
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Challenge Nine
Easy3
Math, String+1
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Computational ethnography
Easy3
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Natives
Easy3
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Mental Arithmetic Board Sum
Easy3
Array, Simulation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Is It Even?
Easy3
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Travelling Caterpillar
Easy3
Tree, DFS
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Boardle
Easy3
Intervals, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
I Really Can't Whistle
Easy3
String, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Invested Money
Easy3
Implementation, Math
No attempts yet
Time limit
0.1s
Memory limit
1024 MB
Judgeable
Med
Easy3
Sorting, Greedy+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Air Conditioner
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bottle Arrangements
Easy3
Greedy, Math+1
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Infinity Area
Easy3
Simulation, Math
No attempts yet
Time limit
20s
Memory limit
1024 MB
Judgeable
Palindromic Factors
Easy3
Math, Number theory
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
3D Printing
Easy3
Greedy, Implementation
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Anagram
Easy3
Hash map, String+1
No attempts yet
Time limit
4s
Memory limit
256 MB
Judgeable
Robin Hood
Easy3
Heap, Simulation
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
RetypeGiven N levels, current level K, and sword level S, compare restarting from level 1 against walking back to S, and report the smaller total time including time already spent.	Easy3	MathImplementation+1	No attempts yet	20s	1024 MB	Judgeable
ZOAC 4Given an H by W grid, place as many people as possible so any two differ by more than N rows or more than M columns.	Easy3	GreedyMath+1	No attempts yet	1s	512 MB	Judgeable
Common AnagramsCount the substrings of A whose character multiset matches the multiset of some contiguous substring of B of the same length.	Easy3	Hash mapString+2	No attempts yet	20s	1024 MB	Judgeable
ZathrasSimulate a yearly update of two robot populations, applying pairing, births with percentages, and 1% decommissioning, for Y years.	Easy3	SimulationImplementation+2	No attempts yet	20s	1024 MB	Judgeable
Impartial OfferingsAssign each pet a treat count so equal sizes get equal counts and larger sizes get strictly more, minimizing the total treats.	Easy3	SortingGreedy+2	No attempts yet	10s	1024 MB	Judgeable
Garden (Easy)Fill an N by M grid where each cell is yellow if its left and upper neighbors match, red otherwise, then report the bottom-right cell's color.	Easy3	Dynamic programmingSimulation+2	No attempts yet	1s	512 MB	Judgeable
Rare NumberGiven a list of N integers, print the value that occurs the fewest times, breaking ties by choosing the smallest value.	Easy3	Hash mapArray+1	No attempts yet	2s	1024 MB	Judgeable
ContestParse a contest log in time order and compute each participant's total score using the per-problem formula with wrong-answer penalties.	Easy3	SimulationImplementation+2	No attempts yet	1s	1024 MB	Judgeable
ScoreGiven n exam scores, output each student's rank in input order, where ties share the same rank.	Easy3	SortingArray+1	No attempts yet	5s	1024 MB	Judgeable
Fiber Optic Network (Fiber)Given n cities and m existing undirected fiber links, find the minimum number of new links needed to connect all cities into one component.	Easy3	Union-findGraph+2	No attempts yet	1s	1024 MB	Judgeable
Tokyo2020Given medal records for each year, find the earliest year with the most golds and the earliest year with the most total medals.	Easy3	ImplementationHash map+1	No attempts yet	8s	1024 MB	Judgeable
Rabbit HoleGiven the final line order of N beavers after passing three holes, find each hole's depth, where a hole holds beavers as a stack until the last beaver pulls them out.	Easy3	SimulationBrute force+1	No attempts yet	2s	1024 MB	Judgeable
Mind ReadingSimulate arithmetic operations on a symbolic expression a*x + b, then check whether a equals 0 and b is an integer.	Easy3	MathImplementation+1	No attempts yet	2s	1024 MB	Judgeable
ChopsticksGiven N kinds of chopsticks in unlimited supply, find how many must be drawn to guarantee R pairs in the worst case.	Easy3	MathCombinatorics+2	No attempts yet	1s	512 MB	Judgeable
What makes 2022 special?Given N and base d, find the smallest number above N whose base-d digits are each of 0 to d-1 used exactly once.	Easy3	MathBrute force	No attempts yet	1s	1024 MB	Judgeable
GardenGiven two rectangles stacked with their left sides aligned, count the 1x1 tiles that surround the bed, corners included.	Easy3	MathImplementation	No attempts yet	0.1s	1024 MB	Judgeable
Book CoversGiven a textbook and two covers, each described by two sides in centimeters and millimeters, pick the fitting cover with the smallest width, or report none.	Easy3	ImplementationMath+1	No attempts yet	0.5s	1024 MB	Judgeable
Guess the digitGiven an equation with one +, - or * and numbers containing ? placeholders, find the smallest digit (distinct from given digits) that makes it true, or print mistake.	Easy3	Brute forceImplementation+2	No attempts yet	1s	1024 MB	Judgeable
РАВЕНСТВОGiven positive integers a, b, c with c < b and x guaranteed integer, compute x = (b - c) / a.	Easy3	MathImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Painting the FenceGiven two painted segments [A,B] and [C,D] on a fence, find how many boards are painted at least once.	Easy3	IntervalsMath+1	No attempts yet	1s	1024 MB	Judgeable
ДИНИGiven four watermelon weights, split them between two hands so the absolute difference of the two sums is as small as possible.	Easy3	Brute forceArray+1	No attempts yet	1s	1024 MB	Judgeable
Algorithm Class - Asymptotic Notation 2Given f(n) = a1n + a0 and constants c, n0, decide whether cn <= f(n) holds for every n >= n0, printing 1 or 0.	Easy3	MathImplementation+2	No attempts yet	1s	512 MB	Judgeable
Algorithm Class - Asymptotic Notation 3Given f(n) = a1n + a0 and constants c1, c2, n0, decide whether c1n <= f(n) <= c2*n holds for every n >= n0.	Easy3	MathImplementation	No attempts yet	1s	512 MB	Judgeable
Two AlbumsGiven two albums of distinct stamp numbers, find how many numbers appear in both and list them in increasing order.	Easy3	SortingHash map+2	No attempts yet	0.4s	1024 MB	Judgeable
SpecialFind the longest substring with all distinct characters and print its length, start index, and the substring itself, preferring the rightmost one.	Easy3	Sliding windowString+2	No attempts yet	0.4s	1024 MB	Judgeable
ИЗРАЗArrange three given non-negative integers and insert +, -, and * (each used once) to maximize the expression's value.	Easy3	Brute forceMath+2	No attempts yet	1s	1024 MB	Judgeable
ElevatorFour children with known weights share an elevator with a passenger limit and a weight limit; find the minimum number of trips.	Easy3	Brute forceImplementation+2	No attempts yet	1s	1024 MB	Judgeable
GameGiven four boxes holding some of the numbers 1 to 4, output the numbers that must fill the empty boxes, or the first two box contents when none are empty.	Easy3	ArrayImplementation+2	No attempts yet	1s	1024 MB	Judgeable
Distinct lengths of runs of zerosGiven a binary string, count how many distinct lengths appear among its maximal runs of consecutive zeros.	Easy3	StringSimulation+2	No attempts yet	1s	1024 MB	Judgeable
СПОРТGiven up to seven distinct lowercase letters, print every permutation of them in lexicographic order, one permutation per line.	Easy3	BacktrackingRecursion+2	No attempts yet	1s	1024 MB	Judgeable
Honey ExhibitionGiven three honey prices and three container capacities, assign each container a distinct honey kind to maximize total earnings.	Easy3	Brute forceGreedy+2	No attempts yet	1s	1024 MB	Judgeable
Two's ComplementGiven N up to 10^9, count how many of the 32 bits differ between N and its 32-bit two's complement.	Easy3	Bit manipulationMath+1	No attempts yet	1s	512 MB	Judgeable
Microwave Again?Given a target cooking time as M:S, find the fewest presses of the 10 sec, 1 min, 10 min, and start buttons that set the timer to exactly that time.	Easy3	GreedyMath+1	No attempts yet	1s	512 MB	Judgeable
Yeongjae's Stepping StonesCount the paths across an N by M glass bridge where each step moves to one of three adjacent cells in the next row and only tempered glass cells may be stepped on, modulo 1,000,000,007.	Easy3	Dynamic programmingMatrix	No attempts yet	0.5s	512 MB	Judgeable
Finding the JokerGiven N shuffles of a 27-card deck, each defined by a sequence of pile sizes, find the final position of the joker that starts on top.	Easy3	SimulationImplementation	No attempts yet	2s	512 MB	Judgeable
Mult!Scan a sequence of numbers and print each number that is a multiple of the first number of its current round, which then restarts the round.	Easy3	ImplementationSimulation+2	No attempts yet	1s	1024 MB	Judgeable
Algorithm Class - Fibonacci Number 2For a given n, count the base-case calls of recursive Fibonacci and the loop iterations of the DP version, each modulo 1e9+7.	Easy3	MathDynamic programming+2	No attempts yet	1s	512 MB	Judgeable
Algorithm Class - Matrix Path Problem 1Count how many times the base case of a recursive matrix path search runs versus the inner assignment of the dynamic programming version.	Easy3	Dynamic programmingRecursion+2	No attempts yet	1s	512 MB	Judgeable
MultiplicationCount the triples i < j < k with A[i] * A[j] = A[k] in an array of at most 100 positive integers.	Easy3	Brute forceArray+1	No attempts yet	2s	1024 MB	Judgeable
Algorithm Class - Breadth-First Search 3Run BFS from vertex R on an unweighted undirected graph and print each vertex's depth, or -1 if it is unreachable.	Easy3	GraphBFS+2	No attempts yet	1s	512 MB	Judgeable
Encryption MatrixGiven three N by N matrices, check all ordered pairs for which their product equals the third matrix, then output a bitmask score for each matrix based on whether it acts as plaintext, encryption matrix, or ciphertext.	Easy3	MatrixBrute force+1	No attempts yet	0.8s	512 MB	Judgeable
Algorithm Class - Depth-First Search 3Run an iterative DFS from vertex R on an undirected unit-weight graph, visiting neighbors in ascending order, and report each vertex's depth or -1 if unreachable.	Easy3	DFSGraph+2	No attempts yet	1s	512 MB	Judgeable
HerdleGiven a 3x3 answer grid and a 3x3 guess grid, count green squares (exact matches) and yellow squares (right breed, wrong position, capped by breed counts).	Easy3	ImplementationArray+2	No attempts yet	1s	1024 MB	Judgeable
Blob's Apple PiesGiven N positive integers arranged in a circle, find the maximum sum of K consecutive values, where the block may wrap around the end.	Easy3	ArraySliding window+2	No attempts yet	1s	1024 MB	Judgeable
The Next Different NumberFor each position i in a sequence, find the smallest later index j whose value differs from A[i], or -1 if none exists.	Easy3	ArrayImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Good Fours and Good FivesCount the number of unordered ways to write N as a sum of 4s and 5s, or output 0 if no such sum exists.	Easy3	MathBrute force+1	No attempts yet	1s	1024 MB	Judgeable
Code GuessingGiven Alice's two digits and the table positions of the four sorted cards, decide whether Bob's two digits are uniquely determined and print them, else -1.	Easy3	Brute forceImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Stream LagGiven each packet's arrival second in non-decreasing order, compute the total time the client spends idle waiting to play packets in order.	Easy3	SimulationGreedy+2	No attempts yet	1s	1024 MB	Judgeable
OverdraftGiven a sequence of deposits and withdrawals, find the smallest non-negative starting balance so the running total never drops below zero.	Easy3	Prefix sumImplementation+2	No attempts yet	1s	1024 MB	Judgeable
Who Goes There?Assign a site's capacity to schools by taking everyone's first team, then second teams, and so on, then filling leftover spots in registration order.	Easy3	SimulationGreedy+1	No attempts yet	1s	1024 MB	Judgeable
FencesGiven an isosceles triangle formed by two ditches, find the apex angle at the short ditch's end and round it to the nearest degree.	Easy3	GeometryMath+1	No attempts yet	1s	512 MB	Judgeable
Follow the Trace!Given n integers, build a nonempty square matrix using each value at most as many times as it appears, and maximize the diagonal sum.	Easy3	GreedySorting+2	No attempts yet	1s	512 MB	Judgeable
Anno Domini 2022Given two years written as AD or BC, compute how many years passed between January 1 of the earlier year and January 1 of the later one, with no year 0.	Easy3	ImplementationMath+2	No attempts yet	2s	512 MB	Judgeable
Letters Q and FGiven a final n by m grid where non-overlapping Q and F shapes were painted, count how many of each letter Lev drew.	Easy3	ImplementationMatrix	No attempts yet	2s	512 MB	Judgeable
KemijaGiven chemical equations with molecule coefficients and atom counts, check for each one whether both sides contain the same number of every atom type.	Easy3	StringHash map	No attempts yet	1s	512 MB	Judgeable
Parts Management with Hyundai MobisSplit N parts into the fewest groups whose total size stays within A and total weight within B, then print a fixed message for each run.	Easy3	ImplementationGreedy	No attempts yet	1s	1024 MB	Judgeable
MBTICount how many times each of the 16 four-letter MBTI type codes appears in any of the eight directions on an N by M letter grid.	Easy3	MatrixString matching+1	No attempts yet	1s	1024 MB	Judgeable
Sequinary NumeralsConvert a sequinary numeral (base 3/2 digits 0 to 2, leading digit 1 or 2) to its value, printed as an integer or as a mixed number with a reduced fraction.	Easy3	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
CIDRGiven N dotted-quad IPv4 addresses, find the longest network prefix length shared by all of them, printing 32 when no common network exists.	Easy3	Bit manipulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Morse Code PalindromesGiven one line of text, decide whether the Morse code of its letters and digits reads the same forwards and backwards.	Easy3	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
LetterleGiven a secret five-letter word and up to seven guesses, print Wordle-style G, Y, X feedback for each guess until a guess matches or the seventh guess fails.	Easy3	ImplementationArray	No attempts yet	1s	1024 MB	Judgeable
Social DistancingGiven S circular seats with N occupied, find how many more people can sit so that no two seated people are adjacent.	Easy3	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Ticket Completed?Count city pairs connected by claimed rail segments, then divide by the total number of unordered city pairs.	Easy3	Union-findGraph+1	No attempts yet	1s	1024 MB	Judgeable
Wordle with FriendsGiven guesses with their G, Y, and - feedback, list every guessable word that would produce exactly that feedback for all guesses, in input order.	Easy3	SimulationString+1	No attempts yet	1s	1024 MB	Judgeable
BeekeeperGiven word lists, the task is to find the word with the most pairs of identical adjacent vowels, where vowels are a, e, i, o, u, y.	Easy3	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Un-bear-able ZooGiven several test cases of animal descriptions, count each animal by its last word and print the kinds in alphabetical order with their counts.	Easy3	Hash mapSorting+1	No attempts yet	1s	1024 MB	Judgeable
OrnamentsGiven circle radius r, knot distance h, and extra percent s, compute the string length wrapped around the circle, rounded to two decimals.	Easy3	MathGeometry	No attempts yet	1s	1024 MB	Judgeable
RecountGiven one candidate name per vote, find the candidate with strictly more votes than any other, or print Runoff! if no candidate leads outright.	Easy3	Hash mapString	No attempts yet	3s	1024 MB	Judgeable
Set!Given 12 Set cards written as four lines of three codes, list every trio where each of the four attributes is all the same or all different.	Easy3	Brute forceImplementation	No attempts yet	1s	1024 MB	Judgeable
Linden Mayor SystemGiven rewrite rules and a starting string, print the string after applying every rule to every letter for m rounds.	Easy3	StringSimulation+1	No attempts yet	2s	1024 MB	Judgeable
Cracking RSAGiven an RSA public key (n, e) where n is a product of two primes below 1000, find the private exponent d.	Easy3	MathNumber theory+1	No attempts yet	3s	1024 MB	Judgeable
Cookie CuttersScale the polygon by sqrt(A divided by its area), then translate it so the minimum x and y coordinates are both zero.	Easy3	GeometryMath+1	No attempts yet	1s	1024 MB	Judgeable
RailroadGiven X level junctions and Y switches, decide whether they can form a closed track using every piece with no dead ends.	Easy3	MathGraph	No attempts yet	1s	1024 MB	Judgeable
ShiritoriGiven words called in a Shiritori game, find the first player who breaks the rule of starting with the previous word's last letter or reusing a word.	Easy3	StringHash map	No attempts yet	2s	1024 MB	Judgeable
The weight of wordsGiven a length l and a total weight w, build a lowercase string of length l whose letter weights (a is 1, z is 26) sum to w, or report impossible.	Easy3	Dynamic programmingString	No attempts yet	1s	1024 MB	Judgeable
Coconut SplatSimulate the coconut counting game with s syllables and n players, then report the number of the last player left in the circle.	Easy3	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Touchdown!Given the yards gained or lost on each play of a drive, determine whether the team scores a Touchdown, suffers a Safety, or gets Nothing.	Easy3	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
The Grand AdventureGiven strings of items and villains, decide whether Jim can pay each villain the top item of a stack and finish with an empty backpack.	Easy3	StackSimulation	No attempts yet	1s	1024 MB	Judgeable
Competitive Arcade BasketballAdd up each player's points in input order and print the players who first reach at least p points, in the order they reach it, or "No winner!" if none do.	Easy3	Hash mapSimulation	No attempts yet	3s	1024 MB	Judgeable
Escape Wall MariaFind the shortest path from S to any border cell on a grid where U, D, L, R cells can only be entered from one direction and 1 cells are blocked.	Easy3	BFSMatrix	No attempts yet	1s	1024 MB	Judgeable
Spelling BeeGiven a 7-letter Spelling Bee hexagon and a word list, the task is to print every word of length at least 4 that uses only those letters and contains the center letter.	Easy3	StringImplementation	No attempts yet	3s	1024 MB	Judgeable
Musical TreesGiven people and tree positions on a line, each person runs to the nearest tree (smaller position on ties), and a tree goes to one person, so count the people left without a tree.	Easy3	GreedyImplementation	No attempts yet	1s	1024 MB	Judgeable
Speed TypingGiven strings I and P, check whether I is a subsequence of P and report how many letters to delete from P, or IMPOSSIBLE if it is not.	Easy3	StringTwo pointers+1	No attempts yet	Not set	1024 MB	Judgeable
Challenge NineInsert exactly one digit into N so the result is divisible by 9, then output the smallest such number without leading zeros.	Easy3	MathString+1	No attempts yet	Not set	1024 MB	Judgeable
Computational ethnographyCount the numbers from A to B whose digit reversal is also a perfect square, where both the number and its reversal are squares and the reversal has no leading zero.	Easy3	Brute forceMath	No attempts yet	1s	512 MB	Judgeable
NativesGiven n treasure values, find the largest total the captain can keep after giving at least half of the treasures to the chieftain.	Easy3	GreedySorting	No attempts yet	1s	512 MB	Judgeable
Mental Arithmetic Board SumGiven an array, apply point assignments and right cyclic shifts, and print the sum of the board after each command.	Easy3	ArraySimulation	No attempts yet	1s	512 MB	Judgeable
Is It Even?Given N integers and K, decide whether the product of the integers is divisible by 2^K, printing 1 or 0.	Easy3	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Travelling CaterpillarFind the shortest closed walk from root 0 that visits every marked node in a weighted tree, and print its total length.	Easy3	TreeDFS	No attempts yet	1s	1024 MB	Judgeable
BoardleGiven Q directional answers about a hidden treasure on an N by M grid, count the cells where the treasure can still be.	Easy3	IntervalsImplementation	No attempts yet	1s	256 MB	Judgeable
I Really Can't WhistleCount the subsequences of S that spell W, H, then two or more E's (WHEE, WHEEE, and so on), modulo 1,000,000,007.	Easy3	StringDynamic programming	No attempts yet	1s	512 MB	Judgeable
Invested MoneyGiven today's weekday and how many days ago each deposit was made, find the fewest days until a deposit renews, where renewals never fall on weekends.	Easy3	ImplementationMath	No attempts yet	0.1s	1024 MB	Judgeable
MedFor each beekeeper, find the best and worst final rank possible when the sixth round adds 0 to 500 points and the other scores can be chosen freely.	Easy3	SortingGreedy+1	No attempts yet	1s	512 MB	Judgeable
Air ConditionerGiven day N and a clock delay of K minutes, list every time the air conditioner switches off on day N, where each third shutoff stops the internal clock for K minutes.	Easy3	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Bottle ArrangementsConstruct a length-n string of R and W bottles so every requested (r,w) pair appears as the counts in some contiguous interval, or report IMPOSSIBLE.	Easy3	GreedyMath+1	No attempts yet	2s	2048 MB	Judgeable
Infinity AreaGiven R, A, B, sum the areas of circles whose radii alternate between multiplying by A and integer-dividing by B, until a radius reaches zero.	Easy3	SimulationMath	No attempts yet	20s	1024 MB	Judgeable
Palindromic FactorsCount the divisors of A that read the same forward and backward in decimal.	Easy3	MathNumber theory	No attempts yet	2s	1024 MB	Judgeable
3D PrintingFor each test case, choose four ink amounts no larger than every printer's supply that sum to exactly 10^6, or report IMPOSSIBLE.	Easy3	GreedyImplementation	No attempts yet	5s	1024 MB	Judgeable
AnagramGiven a list of lowercase words, print each word whose anagram has not appeared earlier in the list, keeping the input order.	Easy3	Hash mapString+1	No attempts yet	4s	256 MB	Judgeable
Robin HoodGiven N wealths, repeatedly take 100 from the richest person (first on ties) K times and print the final wealth, or impossible if a theft would leave someone at 0 or less.	Easy3	HeapSimulation	No attempts yet	3s	256 MB	Judgeable