Problems
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Total results6,365 problems
| Title | Level | Topics | Solved | Time limit | Memory limit | Judge |
|---|---|---|---|---|---|---|
| AdditionRead two integers between -100,000 and 100,000 and print their sum. | Easy1 | MathImplementation | No attempts yet | 1s | 512 MB | Judgeable |
| CAPSRead a lowercase string and print every character converted to uppercase. | Easy1 | StringImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| Judging MooseGiven the tine counts on each side, print the moose's score as Even x, Odd x, or Not a moose when both sides are zero. | Easy1 | ImplementationMath | No attempts yet | 1s | 512 MB | Judgeable |
| Hard choiceGiven prepared and requested counts for chicken, beef, and pasta, count passengers whose requested meal is unavailable. | Easy1 | MathImplementation | No attempts yet | 1s | 1024 MB | Judgeable |
| Every Second CountsGiven a start and end clock time, compute how many seconds elapsed, adding 24 hours if the ride crosses midnight. | Easy1 | MathImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| AnglesFor each triple of angles, print the numbers and say whether they sum to 180. | Easy1 | ImplementationMath | No attempts yet | 2s | 512 MB | Judgeable |
| RectanglesRead R and C, then print R lines of C asterisks each to draw a rectangle. | Easy1 | Implementation | No attempts yet | 2s | 512 MB | Judgeable |
| Final ScoreGiven the rosters of two teams and the names of the goal scorers, count each team's goals and decide which team scored more. | Easy1 | Hash mapImplementation+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Chanukah CandlesEach evening needs one more candle than the last plus one shammas, so for N days compute N(N+1)/2 + N. | Easy1 | MathImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| Sim CardFor each student, compute the smallest total cost of call minutes and data across the three fixed operator price plans. | Easy1 | ImplementationBrute force+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Vera's FashionGiven N tops and N bottoms colored 1 to N, count how many top and bottom pairs have different colors. | Easy1 | MathCombinatorics+1 | No attempts yet | 2s | 256 MB | Judgeable |
| Fast A+BRead T pairs of integers from fast input and print each sum on its own line. | Easy1 | ImplementationMath+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Sum of N integersRead N integers and print their sum, which needs a 64-bit integer type. | Easy1 | ImplementationMath | No attempts yet | 0.1s | 512 MB | Judgeable |
| Linear Algebra and GroupOutput the sum of the digits appearing in the cover illustration of a specific linear algebra textbook. | Easy1 | ImplementationMath+2 | No attempts yet | 1s | 256 MB | Judgeable |
| SUPER SUPER BINARY SEARCH DELUXE 2.5: THE LEGEND OF THE GOLDEN MAZASSUMNIDA, EPISODE 2: THE MAZWAETL UNIVERSE, PART 2: THE PARALLEL UNIVERSE AND THE LOST MAZASSUMNIDA: GAME OF THE YEAR EDITIONPrint the first midpoint binary search picks on [1, 100], which is 50. | Easy1 | Binary searchImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| YeeRead any amount of input, including none, and print the single word Yee. | Easy1 | ImplementationBrute force | No attempts yet | 2s | 512 MB | Judgeable |
| Yonsei UniversityRead N (0 or 1) and print either YONSEI or Leading the Way to the Future depending on its value. | Easy1 | Implementation | No attempts yet | 1s | 128 MB | Judgeable |
| RectangleImplement a Rectangle class with width and height, range-checked setters, and methods for area, perimeter, and square detection. | Easy1 | ImplementationMath+2 | No attempts yet | 1s | 512 MB | Judgeable |
| The group project starts and the team leader is goneGiven a distance L, Sungwoo covers 1 to 5 per minute; print the smallest integer number of minutes needed to reach Mingeon. | Easy1 | MathImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Who Am IPrint the exact line I'm Sexy. | Easy1 | Implementation | No attempts yet | 1s | 128 MB | Judgeable |
| Helmet and VestGiven a list of helmet defense values and a list of vest values, print the sum of the best helmet and the best vest. | Easy1 | ArrayImplementation+2 | No attempts yet | 1s | 512 MB | Judgeable |
| What Is Your Name Score?Given an uppercase name, sum the alphabetical position of each letter and print the total. | Easy1 | StringImplementation | No attempts yet | 1s | 128 MB | Judgeable |
| Winning ICPCCount how many problems each team fully solved (S = T), then report the team with the most solves, breaking ties by smallest index. | Easy1 | ArrayImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| Simple ArithmeticRead three integers a, b, c and print a times b divided by c within an absolute error of 1e-6. | Easy1 | MathImplementation | No attempts yet | 1s | 1024 MB | Judgeable |
| A New BeginningPrint the fixed string "파이팅!!" with no input, a simple output-only warmup task. | Easy1 | Implementation | No attempts yet | 2s | 256 MB | Judgeable |
| CASIORead two integers N and M and print 1 if they are equal, otherwise 0. | Easy1 | ImplementationMath | No attempts yet | 2s | 256 MB | Judgeable |
| Weird SymbolGiven two integers A and B, compute (A+B)*(A-B) and print the result. | Easy1 | MathImplementation | No attempts yet | 2s | 256 MB | Judgeable |
| General ElectionSum each candidate's votes across regions and print the candidate number with the largest total. | Easy1 | ArrayImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| Passionate SortingRead N numbers and print them in ascending order separated by spaces. | Easy1 | SortingImplementation | No attempts yet | 1s | 512 MB | Judgeable |
| Hongik UniversityRead a year N and print how many years have passed since 1946, so output N minus 1946. | Easy1 | MathImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Jerry and TomSubtract the fraction A/B from 1 and print the remaining cheese as P/Q in lowest terms. | Easy1 | MathNumber theory+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Missing RunnerGiven the numbers 1 to N with exactly one omitted from a list of N - 1 distinct values, report the missing number. | Easy1 | MathImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Happy Birthday, kipa00!The problem asks contestants to output a UTF-8 birthday letter for kipa00, scored by hidden criteria unrelated to algorithmic problem solving. | Easy1 | Implementation | No attempts yet | 1s | 512 MB | Judgeable |
| Serious ProblemCount how many times 2 and e appear in a string of those two characters and report which is more frequent, or yee if tied. | Easy1 | StringImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| BingoPrint the fixed 5x5 bingo board showing which cells are colored, with # for colored and . for empty. | Easy1 | ImplementationSimulation | No attempts yet | 0.999s | 511 MB | Judgeable |
| Is it rated?Given the name of a past Codeforces contest, print 1 if the contest was rated and 0 otherwise. | Easy1 | ImplementationString | No attempts yet | 1s | 512 MB | Judgeable |
| EmojiGiven a short message, determine for each line whether it contains the Slack cat emoji expressed as an ASCII shortcode. | Easy1 | StringImplementation+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Overflowing with SweetnessGiven triples a and c, find triple b with components in 1 to 100 such that performing the defined cake operation a cake b yields c. | Easy1 | MathImplementation+2 | No attempts yet | 1s | 256 MB | Judgeable |
| Sort Master Bae JihoonGiven N integers, print the largest value, which is the last element after sorting in ascending order. | Easy1 | ArrayImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Endgame SpoilerThe input is the plot of Avengers: Endgame, and the required output is the film's English title. | Easy1 | Implementation | No attempts yet | 1s | 512 MB | Judgeable |
| Greetings!Given a greeting of the form h followed by e's and a y, print the same greeting but with twice as many e's. | Easy1 | StringImplementation | No attempts yet | 1s | 512 MB | Judgeable |
| Animal King ElectionRead nine votes, each either Tiger or Lion, and print the candidate who received more than half of them. | Easy1 | ImplementationString | No attempts yet | 1s | 512 MB | Judgeable |
| Telephone Directory Information RoutingGiven a 7-digit phone number, print YES if its first three digits are 555, otherwise NO. | Easy1 | ImplementationMath | No attempts yet | 1s | 512 MB | Judgeable |
| Counting ClausesGiven a 3-SAT instance with m clauses and n variables, print satisfactory if it has at least eight clauses and unsatisfactory otherwise. | Easy1 | Implementation | No attempts yet | 1s | 512 MB | Judgeable |
| Born in 1998, but 2541 in Thailand?!Given a Buddhist calendar year between 1000 and 3000, print the corresponding Gregorian year by subtracting 543. | Easy1 | MathImplementation+2 | No attempts yet | 1s | 1024 MB | Judgeable |
| What an Easy ProblemImplement a function that returns the move losing to Kyojun each round, given the move he announces before playing. | Easy1 | ImplementationSimulation | No attempts yet | 1s | 512 MB | Judgeable |
| Find the VerticesAn interactive-style task where a hidden edge between two vertices must be identified by querying the grader; input is fixed by the grader, not read. | Easy1 | GraphImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| RatsGiven three counts from a mark-recapture study, compute the Chapman estimator using the stated floor formula and print it. | Easy1 | MathImplementation+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Extreme TemperaturesRead lines that pair a date with integer temperatures and print the smallest and largest values across every measurement. | Easy1 | ImplementationArray+2 | No attempts yet | 2s | 512 MB | Judgeable |
| PetrolGiven the petrol n used next month and the leftover quota k, compute the cost where the first 60+k liters cost 1500 each and the rest cost 3000 each. | Easy1 | MathImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| HOMWRKRead pairs of integers and print each pair's sum followed by its product on one line. | Easy1 | MathImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| Three IntegersGiven three integers, each either 1 or 2, print whichever value appears more often. | Easy1 | Implementation | No attempts yet | 2s | 512 MB | Judgeable |
| Counting VowelsCount how many characters in a lowercase string are one of the vowels a, i, u, e, o. | Easy1 | StringImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| ExamRead three scores and print the sum of the two largest. | Easy1 | ArrayImplementation+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Inversion of a StringReverse the substring of S from position A to position B, keep the rest unchanged, and print the resulting string. | Easy1 | StringImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| ModeCount how many times each value from 1 to M appears in the sequence and print the largest count. | Easy1 | ImplementationArray | No attempts yet | 2s | 512 MB | Judgeable |
| The Walking AdamGiven a string of 'U' and 'D' steps, find the index of the first 'D', or the string length if no 'D' appears. | Easy1 | StringImplementation+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Beginning the HuntA joke problem with no input that asks for a fixed uppercase answer with no spaces. | Easy1 | Implementation | No attempts yet | 1s | 512 MB | Judgeable |
| A+B (MC)Build a Minecraft redstone circuit that reads two integers from a command interpreter and outputs their sum. | Easy1 | SimulationImplementation+1 | No attempts yet | 1s | 512 MB | Judgeable |
| You can submit after 0 seconds.Given the time of the most recent submission and a delay k, submit at or before T + k seconds; there is no input and any output works. | Easy1 | Implementation | No attempts yet | 1.001s | 512 MB | Judgeable |
| Print N MPrint the integers from 1 to N*M as N lines of M space-separated numbers each. | Easy1 | Implementation | No attempts yet | 1s | 512 MB | Judgeable |
| Dog TreatsRead the counts of small, medium, and large treats, compute 1*S + 2*M + 3*L, and print happy if the score is at least 10, otherwise sad. | Easy1 | MathImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| Random Game~~~~~Output any integer between 1 and 2,147,483,647; the judge scores each of three runs by how close your number lands to a hidden random pick. | Easy1 | MathProbability+2 | No attempts yet | 1s | 256 MB | Judgeable |
| Barn LotteryGiven N cows and a W by H barn, find how many L by L square spaces fit inside the barn, capped at N. | Easy1 | MathImplementation+2 | No attempts yet | 1s | 1024 MB | Judgeable |
| Command PromptGiven N equal-length file names, output a pattern where each position is the common character if all names agree there, or a question mark otherwise. | Easy2 | StringImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Hansu NumbersCount integers from 1 to N (N up to 1000) whose digits form an arithmetic sequence. | Easy2 | ImplementationBrute force+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Make It DivisibleFind the smallest two-digit replacement (00-99) for the last two digits of N that makes N divisible by F. | Easy2 | Brute forceMath+1 | No attempts yet | 2s | 128 MB | Judgeable |
| White SquaresGiven an 8x8 board marked with pieces and empty cells, count how many pieces sit on the white squares of the standard alternating coloring. | Easy2 | ArrayImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Word CountCount the number of space-separated words in a string that may have leading or trailing spaces. | Easy2 | StringImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Most Frequent LetterCount letter frequencies in a string, case-insensitively, and print the most common letter in uppercase or a question mark on ties. | Easy2 | Hash mapString+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Basketball GameGiven N surnames, count first letters and print all letters (in order) that start at least five surnames, or PREDAJA if none does. | Easy2 | Hash mapImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Octal to BinaryConvert a huge octal number (up to 333,334 digits) into its binary representation without leading zeros. | Easy2 | StringImplementation+1 | No attempts yet | 1s | 256 MB | Judgeable |
| Sign of Integer SumsFor three separate lists of integers, compute each sum and print whether it is positive, negative, or zero, handling values up to 64-bit signed range. | Easy2 | ImplementationMath | No attempts yet | 2s | 256 MB | Judgeable |
| Splitting a WordSplit a lowercase word into three nonempty parts, reverse each part, and find the lexicographically smallest concatenation among all splits. | Easy2 | StringBrute force+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Mobile Phone BillGiven up to 20 call durations, compute total cost under two per-block billing plans and print the cheaper one with its cost. | Easy2 | SimulationImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| House Number SignCompute the total width of a house-number sign given fixed per-digit widths and 1 cm margins between digits and at both ends, for each input number until 0 appears. | Easy2 | ImplementationString+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Easy Sequence SumGiven a sequence where each integer k repeats k times, compute the sum of terms between positions A and B. | Easy2 | MathSimulation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Choosing a Team NameCount letters L,O,V,E across a fixed name plus each candidate string, compute a formula mod 100, and print the candidate with the highest value, breaking ties by lexicographic order. | Easy2 | StringImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| TV SizeGiven a TV's diagonal length and height-to-width ratio, compute the actual height and width, flooring non-integer results. | Easy2 | MathImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Group Word CheckerCount how many of up to 100 lowercase words have every repeated character forming a single contiguous block. | Easy2 | StringImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Year Progress BarGiven a date and time string, compute what percentage of the current year (accounting for leap years) has elapsed. | Easy2 | ImplementationMath | No attempts yet | 2s | 128 MB | Judgeable |
| Actual Disk SpaceGiven N file sizes and a cluster size, compute total disk space used by rounding each file up to the nearest cluster multiple and summing. | Easy2 | MathImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Yujin NumberGiven an integer up to about 2.1 billion, determine whether some split of its digits into a left and right part yields equal digit products. | Easy2 | StringBrute force+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Reversed AdditionReverse the digits of two numbers up to 1000, add the reversed values, then reverse the sum and print the result. | Easy2 | MathImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| PetSimulate feeding and exercising a pet's weight across scenarios and report whether it ends happy, sad, or dead based on simple weight thresholds. | Easy2 | SimulationImplementation | No attempts yet | 1s | 128 MB | Judgeable |
| Most Frequent LettersCount lowercase letter frequencies across up to 50 lines of text and print all letters tied for the highest frequency in alphabetical order. | Easy2 | Hash mapString+1 | No attempts yet | 2s | 128 MB | Judgeable |
| EarringsGiven girl names and 2n-1 confiscation/return records tagged with a number and a letter, find the girl whose number appears only once and thus never got her earring back. | Easy2 | Hash mapArray+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Floor DecorationCount the number of wooden planks by counting maximal runs of consecutive '-' in each row and '|' in each column of a grid. | Easy2 | MatrixImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| 24-Hour MissionGiven the current time and a start time in HH:MM:SS, compute the time remaining until the start time next occurs within a 24-hour cycle. | Easy2 | MathImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Sort Digits DescendingRearrange the digits of a given natural number so they appear in descending order and print the result. | Easy2 | SortingString+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Organizing BooksSimulate packing books into boxes in order, sealing a box once the next book no longer fits, and sum the leftover capacity of every box. | Easy2 | SimulationImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Time MachineGiven three two-digit numbers from a digital clock, count how many of the 6 permutations form a valid HH:MM:SS time. | Easy2 | CombinatoricsBrute force+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Internet Cafe Seat RequestsGiven a sequence of seat requests for 100 computers, count how many requests are rejected because the requested seat is already taken. | Easy2 | SimulationArray+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Room NumberGiven a room number, count how many plastic digit sets (0-9 each) are needed, treating 6 and 9 as interchangeable when flipped. | Easy2 | MathImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Adjusted AverageGiven N exam scores, rescale each by dividing by the maximum score and multiplying by 100, then output the average of the rescaled scores. | Easy2 | ArrayMath+1 | No attempts yet | 2s | 128 MB | Judgeable |
| BallTrack which of three cups covers a ball as cups swap positions M times, then output the cup number holding it. | Easy2 | SimulationImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Sequence TransformationRepeatedly replace a sequence with its adjacent differences K times and print the resulting shorter sequence. | Easy2 | ArraySimulation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Manhattan Distance on a Four-Row Number BoardGiven two numbers placed column by column in a 4-row grid, compute the Manhattan distance between their cell positions. | Easy2 | MathImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Trophy DisplayCount how many trophies form a visible prefix-maximum sequence when scanning the row from the left and separately from the right. | Easy2 | ArrayImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Break-Even PointGiven fixed cost A, variable cost B, and price C, find the smallest number of laptops where revenue exceeds total cost, or -1 if impossible. | Easy2 | MathImplementation | No attempts yet | 0.35s | 128 MB | Judgeable |