Problems
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Total results6,365 problems
| Title | Level | Topics | Solved | Time limit | Memory limit | Judge |
|---|---|---|---|---|---|---|
| Next Term in a SequenceGiven a sequence that is either arithmetic or geometric, determine which type it is and output its next term. | Easy2 | MathImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Fraction SumAdd two given fractions and output the sum reduced to lowest terms using GCD. | Easy2 | MathNumber theory+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Concatenating Numbers 1Compute the total digit count when integers from 1 to N are written consecutively without spaces. | Easy2 | MathImplementation | No attempts yet | 0.15s | 128 MB | Judgeable |
| Octopus NumbersConvert base-8 strings using nine special symbols (including one for digit -1) into their decimal integer values until a terminator line appears. | Easy2 | StringMath+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Good License PlatesFor each license plate, compute a base-26 value from the three letters and compare it to the four-digit number, printing whether their difference is within 100. | Easy2 | StringImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Fourth PointGiven two adjacent sides of a parallelogram as endpoint coordinates, compute and print the fourth vertex for each line of input. | Easy2 | GeometryMath+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Year 2007Given a month and day in 2007, compute and print the corresponding day of the week starting from Monday, Jan 1. | Easy2 | MathImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Counting Pentagon PointsCompute the total pentagonal points after N steps using a simple arithmetic formula, modulo 45678. | Easy2 | MathImplementation | No attempts yet | 2s | 256 MB | Judgeable |
| Perfect SquaresGiven two numbers M and N up to 10000, sum all perfect squares in that inclusive range and print the smallest one, or -1 if none exist. | Easy2 | MathBrute force+1 | No attempts yet | 2s | 128 MB | Judgeable |
| PlugsGiven N power strips each with a plug capacity, compute the max number of computers powered when strips are chained from one wall outlet. | Easy2 | MathGreedy+1 | No attempts yet | 2s | 256 MB | Judgeable |
| Self-Replicating NumberCheck whether squaring an integer N reproduces N as the trailing digits of N squared. | Easy2 | MathImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Day of the YearGiven day, month, year, compute the day's ordinal number within that year accounting for leap years, until a 0 0 0 terminator. | Easy2 | ImplementationMath | No attempts yet | 1s | 128 MB | Judgeable |
| Number GameRepeatedly sum decimal digits of each number until one digit remains, processing lines until a terminating zero. | Easy2 | MathImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Prime WordSum letter values (a-z=1-26, A-Z=27-52) for a word and print whether the sum is prime (with 1 counted as prime). | Easy2 | StringMath+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Dobby's Case-Insensitive Word TestFor each test case, output the original-cased word that is smallest in dictionary order when comparisons ignore letter case. | Easy2 | StringSorting+1 | No attempts yet | 1s | 128 MB | Judgeable |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| Refrigerator MagnetsRead lines until END and print each line that contains no repeated letter, ignoring spaces. | Easy2 | ImplementationString+2 | No attempts yet | 1s | 128 MB | Judgeable |
| VotingFor each recorded vote, check quorum and compare yes and no counts to print the outcome. | Easy2 | ImplementationString | No attempts yet | 1s | 128 MB | Judgeable |
| Mirror ImageFor each word until the terminator '#', print the string reversed with each letter replaced by its mirror image, or INVALID if any letter lacks a mirror. | Easy2 | StringHash map+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Gnome SequencingFor each of N triples of beard lengths, decide whether the three values are strictly increasing or strictly decreasing, then print Ordered or Unordered. | Easy2 | ImplementationSorting+2 | No attempts yet | 1s | 128 MB | Judgeable |
| Remove the DuplicatesFor each test case, collapse every run of consecutive equal numbers into a single value and print the result. | Easy2 | ArrayImplementation | No attempts yet | 1s | 128 MB | Judgeable |
| Rock, Paper, ScissorsGiven two equal-length strings of R, P, S moves, count the rounds each player wins. | Easy2 | StringImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| ParityRead bit strings whose last bit is missing plus a parity letter, and append the 0 or 1 that makes the parity match. | Easy2 | StringBit manipulation+1 | No attempts yet | 1s | 128 MB | Judgeable |