Problems

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Total results21,151 problems

Sum of Consecutive IntegersEasy2
Math, ImplementationNo attempts yetTime limit0.25sMemory limit128 MB
Judgeable
Weather Intern's Temperature SumEasy2
Sliding window, ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Right-Aligned StarsEasy2
Implementation, SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Star Printing - 6Easy2
Implementation, SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Star Printing - 7Easy2
ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Star Printing - 8Easy2
Implementation, SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Intelligent TrainEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Intelligent Train 2Easy2
Simulation, ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Dice GameEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Three DiceEasy2
ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Longest Digit RunEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Find the K-th DivisorEasy2
Math, Brute forceNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Score CalculationEasy2
Array, Simulation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Card GameEasy2
Simulation, ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
AI Oven ClockEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Candy Teacher Go ChangyoungEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Maximum ValueEasy2
Array, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Digit Counts in a ProductEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Average and ModeEasy2
Array, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
VirusEasy2
Graph, BFS +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Greatest Common Divisor and Least Common MultipleEasy2
Math, Number theoryNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Coin GameEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Third Largest NumberEasy2
Sorting, ArrayNo attempts yetTime limit1sMemory limit32 MB
Judgeable
CryptoquoteEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
U.S. Unit ConversionEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Laundry Owner DonghyukEasy2
Greedy, Math +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Weighted Triangular SumEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Binary AdditionEasy2
String, Simulation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Matrix MultiplicationEasy2
Matrix, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Base ConversionEasy2
Math, Implementation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Fibonacci Number 2Easy2
Dynamic programming, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Sort Numbers 2Easy2
Sorting, ImplementationNo attempts yetTime limit2sMemory limit256 MB
Judgeable
What Is This Semester's GPA?Easy2
Implementation, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Triangular Gimbap Price ComparisonEasy2
Math, Greedy +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Score CalculationEasy2
Sorting, Array +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Sugar DeliveryEasy2
Greedy, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Uphill RoadEasy2
Array, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Super MarioEasy2
Array, Brute force +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Maximum Value of a Fraction TableEasy2
Brute force, Implementation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Difference Between 5 and 6Easy2
String, Greedy +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Climbing SnailEasy2
Math, SimulationNo attempts yetTime limit0.25sMemory limit128 MB
Judgeable
Monster TruckEasy2
Matrix, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Why Is KMP Called KMP?Easy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
CopyrightEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
DominoesEasy2
Math, CombinatoricsNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Sorting Wooden PiecesEasy2
Simulation, Sorting +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Year 2009Easy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
I Am a ChefEasy2
Array, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Changyeong's DiaryEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Answer Pattern GuessingEasy2
Simulation, String +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
ATM TransactionsEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
OctalEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Chessboard PiecesEasy2
Math, GreedyNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Fourth PointEasy2
Geometry, Math +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Equal-Size Interval ClusteringEasy2
Sorting, Array +1No attempts yetTime limit5sMemory limit128 MB
Judgeable
Changyeong Village Cup ShuffleEasy2
Simulation, StringNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Time Until the WarningEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Angry ChangyoungEasy2
Geometry, Math +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
ScannerEasy2
Simulation, Implementation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Snow White and the Seven DwarfsEasy2
Brute force, ArrayNo attempts yetTime limit1sMemory limit128 MB
Judgeable
15-Puzzle DisplacementEasy2
Array, Math +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Find the Even NumbersEasy2
Array, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Number ReversalEasy2
String, Math +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Scaled ChessboardEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Making an AcronymEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
BUHAEasy2
Array, Simulation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Vigenère Cipher EncryptionEasy2
String, Simulation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Hamming DistanceEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Binary NumberEasy2
Bit manipulation, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Hyunwoo the ProfessorEasy2
MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Automated Telephone ExchangeEasy2
Brute force, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
ElectrificationEasy2
Simulation, Bit manipulationNo attempts yetTime limit2sMemory limit256 MB
Judgeable
FlatEasy2
Implementation, MathNo attempts yetTime limit3sMemory limit256 MB
Judgeable
K-Graph OddityEasy2
Graph, Implementation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Explicit FormulaEasy2
Bit manipulation, Implementation +1No attempts yetTime limit3sMemory limit256 MB
Judgeable
Cutting a BlockEasy2
Math, Simulation +1No attempts yetTime limit2sMemory limit64 MB
Judgeable
Celebrity JeopardyEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Anagram DistanceEasy2
Hash map, String +1No attempts yetTime limit1sMemory limit256 MB
Judgeable
MinesweeperEasy2
Simulation, Implementation +2No attempts yetTime limit1sMemory limit128 MB
Judgeable
Fred's Lotto TicketsEasy2
Array, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
NumbersrebmunEasy2
String, Two pointers +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Right TriangleEasy2
Math, Implementation +2No attempts yetTime limit1sMemory limit128 MB
Judgeable
LogoEasy2
Simulation, Geometry +2No attempts yetTime limit1sMemory limit128 MB
Judgeable
Prerequisites?Easy2
Implementation, Hash map +2No attempts yetTime limit1sMemory limit128 MB
Judgeable
AFC WimbledonEasy2
Math, Implementation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Combination LockEasy2
Simulation, Math +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Above AverageEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Time ZonesEasy2
Implementation, Math +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Hay PointsEasy2
Hash map, StringNo attempts yetTime limit1sMemory limit128 MB
Judgeable
BabelfishEasy2
Hash map, String +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Keyboard Shifted One Key RightEasy2
Hash map, String +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Dog & GopherEasy2
Implementation, GeometryNo attempts yetTime limit1sMemory limit128 MB
Judgeable
War for Middle-earthEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Always Follow the Rules in ZombielandEasy2
Array, Implementation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Tetrahedral Stacks of CannonballsEasy2
Math, Implementation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Rock Paper Scissors?Easy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Bubble Gum, Bubble Gum, in the Dish, How Many Pieces Do You Wish?Easy2
Array, Simulation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Find MultiplesEasy2
Implementation, Math +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Number Card GameEasy2
Simulation, Implementation +2No attempts yetTime limit1sMemory limit128 MB
Judgeable
Pizza PricingEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Sum of Consecutive IntegersGiven two integers, print the sum of all integers in the closed range between them, handling either order.	Easy2	MathImplementation	No attempts yet	0.25s	128 MB	Judgeable
Weather Intern's Temperature SumGiven N daily temperatures, find the maximum sum over any contiguous window of exactly K days.	Easy2	Sliding windowArray	No attempts yet	1s	128 MB	Judgeable
Right-Aligned StarsPrint N lines of right-aligned stars, where line i has i stars padded with leading spaces to align the right edge.	Easy2	ImplementationSimulation	No attempts yet	1s	128 MB	Judgeable
Star Printing - 6Print a centered triangle of stars whose width decreases by 2 each line from 2N-1 down to 1.	Easy2	ImplementationSimulation	No attempts yet	1s	128 MB	Judgeable
Star Printing - 7Print a diamond shape of asterisks with a given height using spacing and counting rules.	Easy2	Implementation	No attempts yet	1s	128 MB	Judgeable
Star Printing - 8Print a diamond-like star pattern of width 2N where side star counts rise from 1 to N then fall back to 1, with spaces filling the middle.	Easy2	ImplementationSimulation	No attempts yet	1s	128 MB	Judgeable
Intelligent TrainSimulate passengers getting off and on at four stations and output the maximum train occupancy at any point.	Easy2	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Intelligent Train 2Given boarding and alighting counts at 10 stations, simulate the running passenger total and print its maximum value.	Easy2	SimulationArray	No attempts yet	1s	128 MB	Judgeable
Dice GameFor each player's three dice rolls, compute a prize using given rules and print the maximum prize among all players.	Easy2	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Three DiceGiven three dice values from 1 to 6, compute a prize following fixed rules for triples, pairs, or all different values.	Easy2	Implementation	No attempts yet	1s	128 MB	Judgeable
Longest Digit RunFor three given eight-digit numbers, print the length of the longest run of identical consecutive digits in each.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Find the K-th DivisorGiven N and K, find and print the K-th smallest divisor of N, or 0 if it doesn't exist.	Easy2	MathBrute force	No attempts yet	1s	128 MB	Judgeable
Score CalculationCompute a total score from a 0/1 sequence where consecutive correct answers score an increasing running count.	Easy2	ArraySimulation+1	No attempts yet	1s	128 MB	Judgeable
Card GameSimulate 10 rounds of card comparisons between two players, scoring points, and determine the overall winner using the most recent non-tied round as a tiebreaker.	Easy2	SimulationArray	No attempts yet	1s	128 MB	Judgeable
AI Oven ClockGiven a start time in hours, minutes, seconds and a duration in seconds, compute the finishing time on a 24-hour clock that wraps around.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Candy Teacher Go ChangyoungCheck whether the total number of candies among N students can be evenly divided among them (sum divisible by N).	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Maximum ValueGiven a 9x9 grid of numbers, find the maximum value and print its row and column position.	Easy2	ArrayImplementation	No attempts yet	1s	128 MB	Judgeable
Digit Counts in a ProductGiven three 3-digit natural numbers, compute their product and count how many times each digit 0 to 9 appears in it.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Average and ModeGiven ten natural numbers, compute and print their average and the most frequently occurring value.	Easy2	ArrayImplementation	No attempts yet	1s	128 MB	Judgeable
VirusCount how many computers other than computer 1 lie in computer 1's connected component of a small undirected graph.	Easy2	GraphBFS+1	No attempts yet	1s	128 MB	Judgeable
Greatest Common Divisor and Least Common MultipleGiven two natural numbers up to 10000, output their greatest common divisor and least common multiple.	Easy2	MathNumber theory	No attempts yet	1s	128 MB	Judgeable
Coin GameCount occurrences of each of 8 possible length-3 head/tail patterns among all consecutive triples in a 40-character coin toss string, for multiple test cases.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Third Largest NumberFor each test case of 10 positive integers, output the third largest distinct-position value in the array.	Easy2	SortingArray	No attempts yet	1s	32 MB	Judgeable
CryptoquoteDecode each ciphertext message by substituting letters using a given 26-letter mapping while preserving spaces.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
U.S. Unit ConversionConvert given values between kilograms/pounds and liters/gallons using fixed conversion factors, rounding to four decimal places.	Easy2	ImplementationMath	No attempts yet	1s	128 MB	Judgeable
Laundry Owner DonghyukGiven a number of cents, output the minimum count of quarters, dimes, nickels, and pennies using a greedy coin breakdown.	Easy2	GreedyMath+1	No attempts yet	1s	128 MB	Judgeable
Weighted Triangular SumCompute a weighted sum of triangular numbers W(n) for up to 300 test cases using a direct formula or loop.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Binary AdditionAdd two binary strings up to length 80 for multiple test cases and print the sum without leading zeros.	Easy2	StringSimulation+1	No attempts yet	1s	128 MB	Judgeable
Matrix MultiplicationRead two matrices of bounded size and print their standard matrix product.	Easy2	MatrixImplementation	No attempts yet	1s	128 MB	Judgeable
Base ConversionConvert a number given in an arbitrary base (2 to 36, using letters for digits above 9) into its decimal value.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
Fibonacci Number 2Compute the nth Fibonacci number for n up to 90.	Easy2	Dynamic programmingMath	No attempts yet	1s	128 MB	Judgeable
Sort Numbers 2Read up to one million distinct integers and print them in ascending order.	Easy2	SortingImplementation	No attempts yet	2s	256 MB	Judgeable
What Is This Semester's GPA?Compute a weighted GPA from a list of courses, credits, and letter grades, rounded to two decimal places.	Easy2	ImplementationMath	No attempts yet	1s	128 MB	Judgeable
Triangular Gimbap Price ComparisonGiven several price rates for gimbap, compute the cheapest cost to buy exactly 1000 grams using the best per-gram rate among all stores.	Easy2	MathGreedy+1	No attempts yet	1s	128 MB	Judgeable
Score CalculationGiven 8 distinct problem scores, output the sum of the top 5 and their original indices in increasing order.	Easy2	SortingArray+1	No attempts yet	1s	128 MB	Judgeable
Sugar DeliveryFind the minimum number of 3kg and 5kg bags that sum to exactly N kilograms, or -1 if impossible.	Easy2	GreedyMath	No attempts yet	1s	128 MB	Judgeable
Uphill RoadGiven a sequence of heights, find the maximum height difference over the longest strictly increasing consecutive run.	Easy2	ArrayImplementation	No attempts yet	1s	128 MB	Judgeable
Super MarioGiven 10 mushroom scores, pick a prefix sum closest to 100 (preferring the larger one on ties) as Mario's final score.	Easy2	ArrayBrute force+1	No attempts yet	1s	128 MB	Judgeable
Maximum Value of a Fraction TableGiven a 2x2 grid of positive integers, find how many 90-degree clockwise rotations (0-3) maximize A/C+B/D, choosing the smallest such count on ties.	Easy2	Brute forceImplementation+1	No attempts yet	1s	128 MB	Judgeable
Difference Between 5 and 6Given two integers, compute the minimum and maximum possible sums after freely swapping digits 5 and 6 in each number.	Easy2	StringGreedy+1	No attempts yet	1s	128 MB	Judgeable
Climbing SnailCompute the number of days for a snail climbing A meters by day and sliding B meters by night to reach a pole of height V.	Easy2	MathSimulation	No attempts yet	0.25s	128 MB	Judgeable
Monster TruckCount 2x2 blocks in a grid without any building, grouped by how many parked cars they contain (0 to 4).	Easy2	MatrixImplementation	No attempts yet	1s	128 MB	Judgeable
Why Is KMP Called KMP?Convert a hyphen-joined full name like Knuth-Morris-Pratt into its initials such as KMP.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
CopyrightGiven A songs and a rounded-up average I, find the smallest total copyrighted melodies consistent with ceil(total/A) = I.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
DominoesGiven N, compute the total dot count across all unique dominoes with halves ranging from 0 to N.	Easy2	MathCombinatorics	No attempts yet	1s	128 MB	Judgeable
Sorting Wooden PiecesSimulate repeated bubble-sort passes on five labeled pieces, printing the arrangement after every swap until sorted.	Easy2	SimulationSorting+1	No attempts yet	1s	128 MB	Judgeable
Year 2009Given a day and month in the year 2009, output the English name of the weekday for that date.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
I Am a ChefGiven four scores each for five contestants, output the number and total score of the contestant with the highest sum.	Easy2	ArrayImplementation	No attempts yet	1s	128 MB	Judgeable
Changyeong's DiaryDecode a string by replacing every vowel-p-vowel triple with the single vowel, restoring the original sentence.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Answer Pattern GuessingGiven an answer string, count matches against three fixed repeating guess patterns and report the highest score and who achieved it.	Easy2	SimulationString+1	No attempts yet	1s	128 MB	Judgeable
ATM TransactionsProcess ATM withdrawal or deposit lines, updating balance but rejecting withdrawals that push it below -200, until a sentinel line ends input.	Easy2	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
OctalConvert a binary string (up to 100 digits) to octal by padding and grouping bits in threes using the given table.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Chessboard PiecesGiven N straight guillotine cuts through a rectangular board, compute the maximum number of resulting pieces.	Easy2	MathGreedy	No attempts yet	1s	128 MB	Judgeable
Fourth PointGiven three corners of an axis-aligned rectangle, compute the coordinates of the missing fourth corner.	Easy2	GeometryMath+1	No attempts yet	1s	128 MB	Judgeable
Equal-Size Interval ClusteringSort points lexicographically, split them into K consecutive groups of nearly equal size, and print each group's coordinate average.	Easy2	SortingArray+1	No attempts yet	5s	128 MB	Judgeable
Changyeong Village Cup ShuffleTrack the position of a ball among three cups after a sequence of swap operations described by characters A, B, C.	Easy2	SimulationString	No attempts yet	1s	128 MB	Judgeable
Time Until the WarningGiven current time and a future warning time in a day, compute the wait time as a difference modulo 24 hours, printing 24:00:00 if they match.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Angry ChangyoungFor each match length, decide if it fits diagonally inside a W by H rectangle and print DA or NE accordingly.	Easy2	GeometryMath+1	No attempts yet	1s	128 MB	Judgeable
ScannerExpand an R by C character grid by repeating each character ZR times vertically and ZC times horizontally, then print the result.	Easy2	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
Snow White and the Seven DwarfsGiven nine distinct numbers, find and print in increasing order the seven of them that sum to exactly 100.	Easy2	Brute forceArray	No attempts yet	1s	128 MB	Judgeable
15-Puzzle DisplacementCompute the total Manhattan distance of each labeled tile from its position in the solved 4x4 15-puzzle board.	Easy2	ArrayMath+1	No attempts yet	1s	128 MB	Judgeable
Find the Even NumbersFor each test case with seven numbers, output the sum and minimum of the even ones among them.	Easy2	ArrayImplementation	No attempts yet	1s	128 MB	Judgeable
Number ReversalFor each number, reverse its digits, add to the original, and print YES if the sum is a palindrome, else NO.	Easy2	StringMath+1	No attempts yet	1s	128 MB	Judgeable
Scaled ChessboardPrint a checkerboard of R by C cells where each cell is scaled to an A by B block of X or dot characters.	Easy2	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Making an AcronymBuild an acronym from the first letters of words in a phrase, skipping a fixed list of filler words unless one is the first word.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
BUHAGiven up to 100 square bomb-range constraints on an A by B grid, count how many cells satisfy all the inside/outside conditions.	Easy2	ArraySimulation+1	No attempts yet	1s	128 MB	Judgeable
Vigenère Cipher EncryptionEncrypt repeated plaintext lines with a repeating key using a shifted Vigenère cipher until a line with 0 appears.	Easy2	StringSimulation+1	No attempts yet	1s	128 MB	Judgeable
Hamming DistanceFor each test case, count the positions where two equal-length binary strings differ and print the Hamming distance.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Binary NumberFor each given integer, output the positions of all bits set to 1 in its binary representation, from least to most significant.	Easy2	Bit manipulationImplementation	No attempts yet	1s	128 MB	Judgeable
Hyunwoo the ProfessorFor each given N, output the number of trailing zeros in N! by counting factors of 5.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
Automated Telephone ExchangeGiven a 3-digit exchange index n, count pairs of two-digit numbers a,b (00-99) such that n - a - b = 0.	Easy2	Brute forceMath	No attempts yet	1s	128 MB	Judgeable
ElectrificationGiven switch-to-lamp toggle mappings and a sequence of switch flips, compute and print the final on/off state of each lamp using parity counting.	Easy2	SimulationBit manipulation	No attempts yet	2s	256 MB	Judgeable
FlatGiven room areas and types, compute total area, total bedroom area, and flat cost using half-weighted balcony area.	Easy2	ImplementationMath	No attempts yet	3s	256 MB	Judgeable
K-Graph OddityCompute the maximum vertex degree in a graph and output the smallest odd integer greater than or equal to it.	Easy2	GraphImplementation+1	No attempts yet	1s	128 MB	Judgeable
Explicit FormulaGiven 10 binary inputs, evaluate a fixed XOR-of-ORs boolean formula (equivalently just count pairs/triplets with at least one 1 and check parity) and output the result.	Easy2	Bit manipulationImplementation+1	No attempts yet	3s	256 MB	Judgeable
Cutting a BlockGiven a box and n, print the coordinates of n equal slabs formed by evenly spaced cuts along the x-axis, each rounded to 8 decimals.	Easy2	MathSimulation+1	No attempts yet	2s	64 MB	Judgeable
Celebrity JeopardyGiven an equation of the form variable = value, output that same equation unchanged, preserving exact spacing.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Anagram DistanceGiven many word pairs, count letters to delete from both so their letter frequency histograms match, using character counts.	Easy2	Hash mapString+1	No attempts yet	1s	256 MB	Judgeable
MinesweeperGiven a grid of mines and empty cells, replace each empty cell with the count of mines in its eight neighbors.	Easy2	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Fred's Lotto TicketsGiven up to 100 lotto tickets of 6 numbers each, decide whether every number from 1 to 49 appears on at least one ticket.	Easy2	ArrayImplementation	No attempts yet	1s	128 MB	Judgeable
NumbersrebmunMap each letter of a company name to its phone keypad digit, then check whether the resulting digit string reads the same forwards and backwards.	Easy2	StringTwo pointers+1	No attempts yet	1s	128 MB	Judgeable
Right TriangleRead triples of side lengths until 0 0 0, and print right if the squares of the two shorter sides sum to the square of the longest, else wrong.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
LogoTrack a turtle's position and heading through forward, backward, left, and right commands, then report the rounded distance from the start.	Easy2	SimulationGeometry+2	No attempts yet	1s	128 MB	Judgeable
Prerequisites?Given Freddie's chosen courses and category minimums, check whether each category has at least the required number of his courses.	Easy2	ImplementationHash map+2	No attempts yet	1s	128 MB	Judgeable
AFC WimbledonGiven the sum and difference of two non-negative scores, print the larger score first, or -1 if no such scores exist.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
Combination LockGiven the dial position and three combination numbers, sum the degrees turned clockwise and counter-clockwise to open the lock.	Easy2	SimulationMath+1	No attempts yet	1s	128 MB	Judgeable
Above AverageFor each class, compute the average score and print the percentage of students scoring strictly above it, rounded to three decimals.	Easy2	MathImplementation	No attempts yet	1s	256 MB	Judgeable
Time ZonesGiven a time and two time zone abbreviations, compute the equivalent wall-clock time in the second zone.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Hay PointsSum dictionary values of words appearing in each job description line block until a single period terminates it.	Easy2	Hash mapString	No attempts yet	1s	128 MB	Judgeable
BabelfishBuild a foreign-to-English word dictionary from the input, then translate each foreign word in the message, printing eh for unknown words.	Easy2	Hash mapString+1	No attempts yet	1s	128 MB	Judgeable
Keyboard Shifted One Key RightReplace every character of each input line with the key immediately to its left on a QWERTY keyboard, leaving spaces unchanged.	Easy2	Hash mapString+1	No attempts yet	1s	128 MB	Judgeable
Dog & GopherGiven the gopher's position, the dog's position, and a list of holes, find the first hole the gopher reaches no later than the dog.	Easy2	ImplementationGeometry	No attempts yet	1s	128 MB	Judgeable
War for Middle-earthFor each battle, compute the weighted score of both armies from six and seven race counts and report the winner or a tie.	Easy2	ImplementationMath	No attempts yet	1s	128 MB	Judgeable
Always Follow the Rules in ZombielandRead q quotes in order, then answer r lookups by printing the quote at that 1-based index, or "No such rule" if out of range.	Easy2	ArrayImplementation+1	No attempts yet	1s	128 MB	Judgeable
Tetrahedral Stacks of CannonballsFor each of n queries, read the base side length and print the problem number, the side length, and the total cannonballs in a tetrahedral stack of that size.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
Rock Paper Scissors?Count each player's round wins in rock paper scissors across n rounds and print the player with more wins, or TIE.	Easy2	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Bubble Gum, Bubble Gum, in the Dish, How Many Pieces Do You Wish?Given a list of names arranged in a circle, a starting person, and a count n, find who is at position n in the count.	Easy2	ArraySimulation+1	No attempts yet	1s	128 MB	Judgeable
Find MultiplesRead n, then read numbers until a sentinel 0, printing for each whether it is a multiple of n.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Number Card GameFor each starting number S, repeatedly replace it with the product of its digits until a single digit appears, printing every value in order.	Easy2	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Pizza PricingFor each menu of pizzas, find the diameter of the pizza with the lowest cost per square inch.	Easy2	ImplementationMath	No attempts yet	1s	128 MB	Judgeable