Problems
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Total results1,798 problems
| Title | Level | Topics | Solved | Time limit | Memory limit | Judge |
|---|---|---|---|---|---|---|
| Birthday GraphRead dates in dd mm yyyy form and print a star per birthday for each of the twelve months, in a numbered case format. | Easy2 | ArrayString+1 | No attempts yet | 5s | 512 MB | Judgeable |
| Outer Triangle SumFor each triangle, add the first and last value of every row plus all values of the last row, counting shared corners once, and print the total. | Easy2 | ImplementationArray+2 | No attempts yet | 10s | 512 MB | Judgeable |
| We Lost Again TodayGiven the runs each team scored in all nine innings, decide whether the Ullim Geminis ever held a lead during a game they ended up losing. | Easy2 | ImplementationSimulation+1 | No attempts yet | 1s | 64 MB | Judgeable |
| I am happy~Given the height N, width M, and a seat number K in row-major order, print the row and column of that seat. | Easy2 | MathImplementation+2 | No attempts yet | 2s | 256 MB | Judgeable |
| Fox SignGiven up to 10 touching pairs among five fingers, decide whether the pattern matches the fox sign: thumb, middle, and ring all touch, while index and little touch nothing. | Easy2 | ImplementationArray | No attempts yet | 0.5s | 512 MB | Judgeable |
| Who Is the Admin?Given nine clubs with N members each, find the club whose best member solved more problems than the best member of every other club. | Easy2 | ImplementationArray+1 | No attempts yet | 1s | 256 MB | Judgeable |
| UphillRead all integers on one line and print Good if they are in non-decreasing order, otherwise Bad. | Easy2 | ArrayImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| Building a distribution tableGiven real numbers in [0,1), count how many fall into each of m equal-length subintervals and print the counts in order. | Easy2 | ImplementationArray+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Qualifiers for the Next PhaseGiven N scores and a minimum cutoff rank K, count how many competitors advance when ties at the K-th score also qualify. | Easy2 | SortingArray+1 | No attempts yet | 1s | 1024 MB | Judgeable |
| Batter UpRead n at-bat outcomes, sum the bases from official at-bats (0 to 4), divide by how many of them are not walks, and print the result to six decimals. | Easy2 | ImplementationMath+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Latin SquaresRead an n by n grid of base-n digit characters and report whether it is a Latin square, and if so whether it is in reduced form. | Easy2 | ImplementationArray+2 | No attempts yet | 1s | 512 MB | Judgeable |
| Grass CuttingAfter each week every cell grows 1 cm, then cells in the chosen rows and columns are reset to 1 cm; report the final heights of the 10x10 grid. | Easy2 | SimulationImplementation+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Recently Used DocumentsSimulate a most-recently-used list of capacity k: each opened document moves to the front, new ones are inserted there and the back is dropped when full, then print the final list. | Easy2 | SimulationImplementation+2 | No attempts yet | 1s | 512 MB | Judgeable |
| Opening CeremonyFor each data set, count how many athletes from each country marched, then report the largest shortfall against that country's registered total. | Easy2 | ArrayImplementation+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Triple JumpFind the first step in [30.0, 30.2], then report 30.0 minus the smallest position among steps at least 3 later, or 0 if none exists. | Easy2 | ImplementationArray | No attempts yet | 2s | 512 MB | Judgeable |
| Shattered CakeGiven the cake's width and the dimensions of all shattered rectangular pieces, sum the piece areas and divide by the width to get the length. | Easy2 | MathImplementation+2 | No attempts yet | 10s | 512 MB | Judgeable |
| Array Manipulation at Moloco (Easy)For each element, count how many earlier elements in the array are smaller, and print those counts one per line. | Easy2 | ArrayBrute force | No attempts yet | 2s | 512 MB | Judgeable |
| Lorem ipsumSplit a fixed Latin placeholder paragraph into words and print the words at indices L through R separated by spaces. | Easy2 | StringImplementation+1 | No attempts yet | 0.1s | 512 MB | Judgeable |
| Lotto number frequencyGiven a number n from 1 to 45, print how often n appears among the six main winning numbers of 700 fixed Nanum Lotto rounds. The counts are precomputed constants. | Easy2 | ImplementationArray | No attempts yet | 1s | 256 MB | Judgeable |
| Midterm Exam GradingGiven point values for N problems and each examinee's O/X results, find the highest scorer, breaking ties by the smallest exam number. | Easy2 | ImplementationArray+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Magic SquareGiven an N by N matrix, decide whether its entries form a magic square with equal row, column, and diagonal sums. | Easy2 | ImplementationMatrix+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Jealous JinseoCheck whether any person in Jinseo's row or column has higher charm than him, printing ANGRY if so and HAPPY otherwise. | Easy2 | ImplementationArray | No attempts yet | 1s | 512 MB | Judgeable |
| It Worked, So Why Is It Wrong?Compare the expected answer with Manyoung's output for each sample and system test case, then print Accepted, Wrong Answer, or Why Wrong!!! according to which group fails. | Easy2 | ImplementationSimulation+2 | No attempts yet | 1s | 512 MB | Judgeable |
| Suchan Is a Marine Boy!!Given N practice records, compute the ratio of their arithmetic mean to the expected value of a value drawn uniformly from them, or print divide by zero. | Easy2 | MathImplementation+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Prize HunterGiven two ranks a and b from two contests, print the total prize money using each contest's published prize table. | Easy2 | ImplementationArray | No attempts yet | 1s | 512 MB | Judgeable |
| HappinessRead N scores and print the difference between the maximum and minimum score. | Easy2 | ArrayImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| Are we there yet?Given four distances between consecutive cities on a line, print the full 5x5 table of distances between every pair of cities. | Easy2 | ArrayPrefix sum+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Income InequalityFor each dataset, count how many incomes are less than or equal to the average income. | Easy2 | ArrayImplementation+1 | No attempts yet | 2s | 512 MB | Judgeable |
| SculptureGiven a grid of distinct neighboring heights, mark each interior cell with 1 if all four adjacent cells are higher, otherwise 0. | Easy2 | ArrayImplementation+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Setting a Time LimitGiven n runtimes in milliseconds and a factor s, output the smallest whole number of seconds that is at least s times the largest runtime. | Easy2 | MathImplementation+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Tour de BINUSSum students over Ayu's left or right walk from x1 and count zero-valued rooms over Budi's walk from x2. | Easy2 | ArrayPrefix sum+1 | No attempts yet | 1s | 512 MB | Judgeable |
| ASCII ArtRead an N by M grid of RGB triples, apply the given intensity formula, map each value to a character via the threshold table, and print the grid. | Easy2 | ImplementationMath+1 | No attempts yet | 1s | 512 MB | Judgeable |
| ChessGiven one square in letter-number notation and another in a 1-to-64 numbering, decide whether the two squares share the same color on a chessboard. | Easy2 | ImplementationMath+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Why Cherry Blossoms Bloomed on Info IslandSplit a sequence of N numbers into four consecutive nonempty groups, maximizing the sum of the four group products. | Easy2 | Brute forceImplementation+1 | No attempts yet | 2s | 256 MB | Judgeable |
| ∑|ΔEasyMAX|Given a sequence of tempos, answer queries that ask for the sum of absolute differences between consecutive values over a range. | Easy2 | Prefix sumArray+2 | No attempts yet | 1s | 256 MB | Judgeable |
| Taxicab DistanceGiven an N by M grid of 0s and 1s with exactly two 1s, print the Manhattan distance between them. | Easy2 | ArrayImplementation+2 | No attempts yet | 1s | 256 MB | Judgeable |
| Wagle Wagle SoongkohanGiven three distinct participation values, print OK if their sum is 100 or more, otherwise print Soongsil, Korea, or Hanyang for the smallest. | Easy2 | ImplementationArray+2 | No attempts yet | 1s | 512 MB | Judgeable |
| BuffoonGiven N vote counts in registration order, output S if the first candidate has the unique most votes, otherwise N. | Easy2 | ImplementationArray+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Scores of Final ExaminationGiven m subjects and n students, with each subject's scores listed in a row, find the maximum total score across students. | Easy2 | ArrayImplementation+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Missing NumbersGiven an increasing list of distinct numbers a child recited, print every integer from 1 up to the last recited number that is missing, or print "good job" if none are. | Easy2 | ArrayImplementation+2 | No attempts yet | 1s | 1024 MB | Judgeable |
| Mangling NamesGiven a table of pronunciation times by vowel and consonant counts, sum the times for each student name and report the total. | Easy2 | ImplementationString+2 | No attempts yet | 2s | 512 MB | Judgeable |
| What Is My Grade?Given 50 distinct scores sorted in descending order and Hongik's score, print the letter grade matching his rank using the fixed cutoffs. | Easy2 | ArrayImplementation+2 | No attempts yet | 1s | 256 MB | Judgeable |
| This Problem’s a Slam DunkGiven the heights of five players on each of two teams, count how many State U players are taller than the opponent they guard after sorting both teams by height. | Easy2 | SortingArray+1 | No attempts yet | 1s | 512 MB | Judgeable |
| License to LaunchFind the earliest index of the minimum value in an array of n space-junk counts and print the zero-based day. | Easy2 | ArrayImplementation+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Hot HikePick a start day for a 3-day trip so the maximum temperature on the first and third days is as low as possible, breaking ties by smallest start day. | Easy2 | Brute forceArray+1 | No attempts yet | 2s | 512 MB | Judgeable |
| I'll Pay, No I'll PayPeople take turns adding to their outstretched amount; find who first reaches the threshold K and on which of their turns. | Easy2 | SimulationImplementation+1 | No attempts yet | 2s | 512 MB | Judgeable |
| KBLTRNSGiven several routes, each with a time and a price, print the smallest time among the routes that reach the destination within the 12 hour limit. | Easy2 | ImplementationArray+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Lucky StraightGiven an even-length number, decide whether the sum of its left-half digits equals the sum of its right-half digits, printing LUCKY or READY. | Easy2 | StringImplementation+2 | No attempts yet | 1s | 256 MB | Judgeable |
| MergeMerge two sorted sequences into one sorted sequence using the given tie-breaking rule, which takes from A when the front elements are equal. | Easy2 | Two pointersImplementation+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Longest Ascending Contiguous SubsequenceGiven a sequence of positive integers, find the length of the longest contiguous run whose elements are non-decreasing. | Easy2 | ArrayImplementation+1 | No attempts yet | 2s | 512 MB | Judgeable |
| ArtGiven N paint drop coordinates, find the smallest axis-aligned rectangle that strictly contains every point, and print its bottom-left and top-right corners. | Easy2 | ImplementationMath+2 | No attempts yet | 2s | 512 MB | Judgeable |
| The Pleasant WalkGiven a sequence of house colors, find the length of the longest contiguous segment in which no two adjacent houses share the same color. | Easy2 | ArrayImplementation | No attempts yet | 1s | 512 MB | Judgeable |
| TreasureGiven two arrays A and B, rearrange A (B stays fixed) to minimize the sum of elementwise products, using the sorted pairing strategy. | Easy3 | GreedySorting+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Number SquareGiven an N by M grid of digits, find the area of the largest axis-aligned square whose four corner cells share the same digit. | Easy3 | Brute forceMatrix+1 | No attempts yet | 2s | 128 MB | Judgeable |
| RGB StreetGiven per-house costs for three colors, compute the minimum total cost to paint all houses in a line so that no two adjacent houses share a color. | Easy3 | Dynamic programmingArray | No attempts yet | 0.5s | 128 MB | Judgeable |
| Finding the RankGiven a sorted list of scores with a capacity limit, compute the rank of a new score or return -1 if the list is full and the score is not higher than the last entry. | Easy3 | ArrayImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Castle GuardsGiven a grid of guards, compute the minimum number of guards to add so every row and column has at least one, which equals the max of empty-row count and empty-column count. | Easy3 | ArrayGreedy+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Switches On and OffSimulate switch toggles where male students flip every multiple of their number and female students flip the largest symmetric interval centered on their number. | Easy3 | SimulationArray+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Symmetric DifferenceGiven two sets of natural numbers, compute the size of their symmetric difference. | Easy3 | Hash mapArray+1 | No attempts yet | 2s | 256 MB | Judgeable |
| War - Land GrabFor each region's list of soldier army IDs, find the majority element that appears more than half the time, or print SYJKGW if none exists. | Easy3 | ArrayHash map | No attempts yet | 10s | 512 MB | Judgeable |
| Knight TourCheck whether a given sequence of 36 squares on a 6x6 board forms a valid closed knight's tour with legal moves between consecutive squares and back to the start. | Easy3 | SimulationArray+1 | No attempts yet | 2s | 128 MB | Judgeable |
| MessagesGiven sheets of names passed around a circle with P/N marks, find who wrote each hurtful (N) message and about whom. | Easy3 | SimulationArray+2 | No attempts yet | 1s | 128 MB | Judgeable |
| Transparent MosaicGiven N rectangular paper sheets on a 100x100 grid, count cells covered by more than M sheets. | Easy3 | ArraySimulation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Lucky TicketFind the longest even-length substring of a digit string whose first half digit sum equals its second half digit sum. | Easy3 | Prefix sumBrute force+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Garbage CollectionSimulate a garbage truck visiting points in order, returning to the dump when its load is full or would overflow, and compute the total distance traveled. | Easy3 | SimulationImplementation+2 | No attempts yet | 1s | 128 MB | Judgeable |
| Woodcut TracesSimulate a tool moving on an N by N grid following U/D/L/R commands, ignoring out-of-bounds moves, and mark each point as unvisited, vertical-only, horizontal-only, or both. | Easy3 | SimulationMatrix+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Firework ShowGiven N firework periods and an end time C, count how many distinct seconds from 1 to C have at least one firework fired by any student. | Easy3 | ArrayMath+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Set DifferenceGiven two sets of up to 500,000 natural numbers each, output the count and sorted list of elements present in A but not in B. | Easy3 | Hash mapSorting+1 | No attempts yet | 2s | 256 MB | Judgeable |
| Maximum Subarray SumGiven up to 100,000 integers, compute the maximum sum of a non-empty contiguous subarray. | Easy3 | Dynamic programmingArray | No attempts yet | 1s | 128 MB | Judgeable |
| Jumong's Armor MaterialsCount how many pairs of given numbers sum to a target value M, using each material at most once per pair. | Easy3 | Two pointersArray+1 | No attempts yet | 2s | 128 MB | Judgeable |
| OvertakingGiven entry and exit orders of N cars, count how many cars are not part of the longest common subsequence, meaning they overtook someone. | Easy3 | Dynamic programmingArray+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Sum of Numbers 2Given N positive integers and a target M, count contiguous subarrays whose sum equals M. | Easy3 | Two pointersPrefix sum+1 | No attempts yet | 0.5s | 128 MB | Judgeable |
| StatisticsGiven N odd integers, compute and print the rounded mean, median, mode (second smallest if tied), and range. | Easy3 | ArraySorting+1 | No attempts yet | 2s | 256 MB | Judgeable |
| Picture ComparisonGiven N small 5x7 grids, find the pair of pictures with the fewest differing cells and output their indices. | Easy3 | Brute forceMatrix+1 | No attempts yet | 2s | 128 MB | Judgeable |
| 2D Array Range SumBuild a 2D prefix sum over an N by M grid and answer up to 10,000 rectangle sum queries in O(1) each. | Easy3 | Prefix sumMatrix+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Magic Square ClassificationRead multiple square matrices and classify each into one of five magic square categories based on row, column, diagonal sums, distinctness, and consecutiveness. | Easy3 | MatrixImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| LCD Display TestPrint a given number in seven-segment LCD style using dashes and bars, scaled to a given digit size. | Easy3 | SimulationImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Seven DwarfsGiven nine distinct heights, find seven that sum to exactly 100 and print them in ascending order. | Easy3 | Brute forceArray+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Axis-Parallel LinesGiven n points, count how many horizontal or vertical lines pass through at least two of them. | Easy3 | Hash mapArray | No attempts yet | 2s | 128 MB | Judgeable |
| Choosing Ice Cream in ItalyGiven N items and forbidden pairs, count the triples of items where no two form a forbidden pair. | Easy3 | Brute forceArray | No attempts yet | 1s | 128 MB | Judgeable |
| SequenceFind the maximum length of a contiguous subarray of digits that is either nondecreasing or nonincreasing. | Easy3 | ArrayDynamic programming+1 | No attempts yet | 1s | 128 MB | Judgeable |
| RunningFor each runner, count how many runners ahead have higher ability and output that count plus one, using a running maximum. | Easy3 | ArrayImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Student Who Raises Both AveragesGiven two groups' IQ lists, count students in the first group whose IQ is below that group's average but above the second group's average. | Easy3 | ArrayMath+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Representative Natural NumberFind the smallest integer minimizing the sum of absolute differences to a list of numbers, which is the lower median. | Easy3 | SortingMath+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Two Representative Natural NumbersGiven up to 5,000,000 integers from 1 to 10,000, output the median (smallest if tie) and the rounded mean as representatives. | Easy3 | MathSorting+1 | No attempts yet | 2s | 256 MB | Judgeable |
| Temperature SequenceFind the maximum sum of any K consecutive elements in an array of N temperatures. | Easy3 | Sliding windowPrefix sum+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Colored PaperGiven up to 100 axis-aligned 10x10 black squares placed on a 100x100 sheet, compute the total area they cover without double-counting overlaps. | Easy3 | ArraySimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| BingoSimulate marking a 5x5 bingo board as numbers are called and find the call count when 3 lines (rows, columns, or diagonals) are first completed. | Easy3 | SimulationArray+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Student LineupSimulate inserting students one by one into a line, each moving forward from the end by a given number of positions, then output the final order. | Easy3 | SimulationArray | No attempts yet | 1s | 128 MB | Judgeable |
| Paper CuttingGiven a rectangular sheet and a series of horizontal or vertical cuts along grid lines, compute the area of the largest resulting piece. | Easy3 | SortingArray+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Line UpFind the minimum number of children to move so the line ends in sorted order, equivalent to N minus the longest increasing subsequence length. | Easy3 | Dynamic programmingArray | No attempts yet | 1s | 128 MB | Judgeable |
| Housing Complex NumberingGiven a binary grid, count connected groups of adjacent 1-cells and print the number of groups plus each group's size in ascending order. | Easy3 | BFSGraph+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Receiving a FaxDecode a run-length-encoded byte stream using control bytes that mark literal or repeated runs, then print the result as hex. | Easy3 | SimulationImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Equal-Sum SegmentsSplit an array into contiguous segments with equal sums and output the smallest possible such common sum. | Easy3 | Prefix sumGreedy+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Memory MasterFor each queried integer, check whether it exists in a large set of stored integers and print 1 or 0 for up to a million queries per test case. | Easy3 | Hash mapArray+1 | No attempts yet | 2s | 256 MB | Judgeable |
| Frog LeapsSimulate a circular arrangement where a proclaimed frog repeatedly swaps forward with its neighbor B times, then output the final order starting from frog 1. | Easy3 | SimulationArray | No attempts yet | 1s | 128 MB | Judgeable |
| Sangbeom's GameGiven a grid with two players' king pieces, compute for each player the sum over all pairs of their kings of the Chebyshev distance between them. | Easy3 | MathArray+1 | No attempts yet | 1s | 128 MB | Judgeable |
| KayakParse a grid to find each of nine teams' kayak position, rank teams by distance from the rightmost kayak cell to the finish line with tie handling. | Easy3 | ImplementationSimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Ancient LockGroup locks by whether one lock's row sequence is a constant horizontal shift of another, and count the number of distinct groups (keys) needed. | Easy3 | ArrayHash map+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Magician Lee MinhyukMirror a given top-left quarter grid horizontally and vertically to build a full card, then flip a single specified cell. | Easy3 | ArrayImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |