Problems
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Total results6,405 problems
| Title | Level | Topics | Solved | Time limit | Memory limit | Judge |
|---|---|---|---|---|---|---|
| The 3n+1 SequenceStarting from the given first term, apply the 3n+1 rule until the value first hits 1 and report that position. | Easy2 | SimulationMath+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Von Neumann and the FlyGiven train speed S, fly speed T, and initial gap D, compute how far the fly travels before the two trains collide. | Easy2 | MathImplementation+2 | No attempts yet | 1s | 512 MB | Judgeable |
| Soccer SkillsAmong all teammates whose distance from you is between a and b, print the position, distance, and angle of the one with smallest x then smallest y. | Easy2 | ImplementationGeometry+1 | No attempts yet | 2s | 512 MB | Judgeable |
| I Work All DayGiven a list of saw settings and a tree height T, pick the setting H that minimizes T mod H, breaking ties by first appearance. | Easy2 | ImplementationBrute force+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Just A MinimGiven a list of note codes, sum their lengths in semibreves and print the exact value. | Easy2 | MathImplementation | No attempts yet | 2s | 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 |
| Coffee MachineGiven the number of employees on each of three floors, pick the floor for one coffee machine that minimizes total daily stair time. | Easy2 | Brute forceMath+1 | No attempts yet | 1s | 1024 MB | Judgeable |
| Happy TrailsGiven trail sections as angles and distances, compute the total elevation change and print it rounded to two decimals. | Easy2 | MathImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| Arggggggh!Follow a start point and a series of compass moves to compute the final coordinates, rounded to 8 decimals. | Easy2 | ImplementationMath+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Life SavingsCompare the savings from one 20%-style whole-purchase coupon against the best way to spend two one-item coupons on two of three items, then print the winning plan and its savings. | Easy2 | Brute forceMath+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Nine KnightsGiven a 5x5 board, check whether it has exactly nine knights with no two attacking each other. | Easy2 | ImplementationSimulation | No attempts yet | 2s | 512 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 |
| No DuplicatesRead a line of space-separated uppercase words and print yes if no word repeats, or no if any word appears more than once. | Easy2 | StringHash map+1 | 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 |
| Congruent NumbersGiven the two legs of a right triangle as fractions p1/q1 and p2/q2, print 1 if the triangle's area is an integer, otherwise 0. | Easy2 | MathNumber theory+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Boolean SatisfiabilityCount the assignments of a disjunction of single literals that make the formula true, where each variable takes true or false. | Easy2 | CombinatoricsMath+2 | No attempts yet | 3s | 512 MB | Judgeable |
| Atomic MassParse a short chemical formula, look up each element's atomic mass, multiply by any following count, and print the total with two decimals. | Easy2 | StringHash map+2 | No attempts yet | 1s | 512 MB | Judgeable |
| Incomplete BookGiven the first book takes k days and each later book takes twice the previous, count how many books finish by day d. | Easy2 | MathSimulation+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Analysis of Advanced AnalyticsGiven daily page counts and a fixed notebook size, count how many notebooks are needed when each day's notes must fit in one notebook without splitting. | Easy2 | SimulationGreedy+1 | 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 |
| Jousting TournamentPrint the fixed elimination schedule that pits competitors 1..n one by one, alternating winners between placeholders a and b. | Easy2 | ImplementationSimulation | No attempts yet | 2s | 512 MB | Judgeable |
| Kiwis vs KangaroosGiven a phrase, score each side by how often its letters appear in KANGAROO or KIWIBIRD, then report the higher score or a tie. | Easy2 | ImplementationString+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Beautiful MusicFor each note sequence, check whether every consecutive pair is 2, 4, or 6 steps apart on the repeating 7-note scale, and print one of two messages. | Easy2 | ImplementationString+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Letter CountCount how often each English letter appears in one line, ignoring case and non-letters, then print 26 rows of stars. | Easy2 | StringImplementation | No attempts yet | 2s | 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 |
| PiratesGiven a lowercase word, find the letter with the highest frequency and print that letter with its count. | Easy2 | StringHash map+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Password checkFor each of N passwords, report valid if it has a lowercase letter, uppercase letter, digit, symbol, and length at least 12, else invalid. | Easy2 | StringImplementation | No attempts yet | 2s | 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 |
| Hissing MicrophoneGiven a lowercase string, check whether it contains two consecutive s characters and print hiss or no hiss. | Easy2 | StringImplementation | No attempts yet | 1s | 512 MB | Judgeable |
| Sum Squared Digits FunctionFor each of P datasets, convert the given integer n to base b, square each digit, and report the total with the dataset number. | Easy2 | MathImplementation+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Santa's GiftsCompute the total straight-line distance from Santa's house through four given points in 3D and check it does not exceed the time limit X. | Easy2 | MathGeometry+2 | No attempts yet | 5s | 512 MB | Judgeable |
| Life ScoreFor each name, sum the letter values (A=1 to Z=26, spaces worth 0) and print the total, or PERFECT LIFE when the total is exactly 100. | Easy2 | StringImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| Big number A+BRead two integers with up to 10000 digits and print their sum without leading zeros. | Easy2 | StringMath+2 | No attempts yet | 1s | 256 MB | Judgeable |
| A Simple ProblemGiven N, print the smallest positive multiple of N squared, which is just N squared itself. | Easy2 | MathImplementation+1 | No attempts yet | 3s | 512 MB | Judgeable |
| Check the CheckRead dish names and price-quantity pairs until the line TOTAL, then print PAY if the waiter's total is at most the sum of price times quantity, else PROTEST. | Easy2 | ImplementationString+1 | 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 |
| Triangles from Five SticksGiven five distinct stick lengths, count how many 3-stick subsets can form a triangle with positive area. | Easy2 | Brute forceGeometry+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Jaccard Similarity ThresholdGiven two small sets of digits, decide whether their Jaccard similarity is greater than 0.5. | Easy2 | ImplementationMath | No attempts yet | 1s | 512 MB | Judgeable |
| PencilsChoose either set X or set Y, buy any number of copies of that one set, and pay the least to reach at least N pencils. | Easy2 | MathImplementation | 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 |
| Hash collision stringsPrint two length-N strings that differ but have equal Java String hashCode values, using the classic Aa/BB collision with a shared prefix. | Easy2 | StringHash map+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Abbey CourtyardGiven the area of a square courtyard, compute the perimeter as 4 times the square root of the area, rounded to six decimal places. | Easy2 | MathImplementation+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Cube BitsConvert each of n decimal integers (up to 3^20) to its base-3 representation without leading zeros. | Easy2 | MathImplementation | No attempts yet | 4s | 512 MB | Judgeable |
| Binary GamePrint the binary representations of 0 through n, concatenated with no separators. | Easy2 | StringImplementation | No attempts yet | 1s | 256 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 |
| RickRead one line and print NO if it exactly matches one of six given phrases, otherwise print YES. | Easy2 | StringImplementation | 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 |
| Exceed or notGiven a, b, and r, print overflow if a*b exceeds r, otherwise print the product a*b. | Easy2 | MathImplementation+1 | No attempts yet | 0.5s | 128 MB | Judgeable |
| Derivative of a polynomial functionParse a linear polynomial written like 3x+5 or -x+2 and print the constant that is its derivative. | Easy2 | StringImplementation+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 |
| TeleportationGiven start a, end b, and a bidirectional teleporter linking x and y, find the minimum tractor distance to move from a to b, with the option to skip the teleporter. | Easy2 | MathImplementation+2 | No attempts yet | 2s | 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 |
| PLAYERJINAH’S BOTTLEGROUNDSGiven the coordinates of three distinct points, decide whether they lie on a single straight line. | Easy2 | GeometryMath+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Master of the Shell GameGiven a string, perform T swaps of characters at the given 0-indexed positions in order and print the final string. | Easy2 | StringSimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Overflow and ModuloMultiply N integers and print the product modulo M, reducing after each multiplication to avoid overflow. | Easy2 | MathImplementation+2 | No attempts yet | 1s | 512 MB | Judgeable |
| What Is Your HandleSort N distinct handles by ASCII dictionary order and print the I-th one. | Easy2 | SortingString+1 | 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 |
| HashingCompute the polynomial rolling hash of a lowercase string using base 31 modulo 1234567891. | Easy2 | ImplementationMath | No attempts yet | 1s | 512 MB | Judgeable |
| Matrix Multiplication CalculatorRead pairs of matrices with dimension lines, multiply them when the inner dimensions match, and print each result row wrapped in vertical bars, or print undefined. | Easy2 | ImplementationMatrix+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Wak Sani SatayGiven daily satay and nasi impit sales, compute weekly net profit from fixed per-stick prices, meat and spice costs, and rounding to two decimals. | Easy2 | ImplementationMath | No attempts yet | 2s | 512 MB | Judgeable |
| Caesar CipherShift every letter of a string by k positions in the alphabet, wrapping around, and leave spaces, periods, and commas unchanged. | Easy2 | StringImplementation+1 | No attempts yet | 1s | 64 MB | Judgeable |
| What Does UCPC Stand For?Given one string, decide whether deleting some characters can leave exactly the subsequence UCPC, case sensitive. | Easy2 | StringGreedy+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Mannequins on the Tracks!!Simulate a trolley moving through three zones under a sequence of wait and lever-pull actions, and count how many mannequins get run over in zone C. | Easy2 | SimulationImplementation | No attempts yet | 2s | 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 |
| Telemarketer or not?Given four digits, print "ignore" if the first and last are 8 or 9 and the middle two are equal, otherwise print "answer". | Easy2 | ImplementationBrute force | No attempts yet | 2s | 512 MB | Judgeable |
| Occupy ParkingCount how many of the N parking spaces show 'C' in both the yesterday string and the today string. | Easy2 | StringImplementation+1 | 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 |
| Larger Sport FacilityCompare the areas of two rectangular sports fields and print which school's field is larger or that it is a tie. | Easy2 | ImplementationMath | No attempts yet | 2s | 512 MB | Judgeable |
| What Is Today's Date?Print the current UTC year, month, and day as three lines, using the system date with no input. | Easy2 | Implementation | No attempts yet | 2s | 128 MB | Judgeable |
| Baby BitesGiven n spoken words that are either "mumble" or a number, check if the i-th number equals i and output "makes sense" or "something is fishy". | Easy2 | ImplementationString | No attempts yet | 1s | 512 MB | Judgeable |
| LukaGiven Luka's fixed position and a walk of unit steps, list the indices of steps after which the walker stands on Luka's cell or one of the eight neighbors. | Easy2 | ImplementationSimulation | No attempts yet | 1s | 512 MB | Judgeable |
| Pascal's TriangleGiven n and k with 1 <= k <= n <= 30, print the k-th entry of row n in Pascal's triangle, equal to C(n-1, k-1). | Easy2 | MathCombinatorics+2 | No attempts yet | 1s | 256 MB | Judgeable |
| Poker HandGiven five distinct cards, report the largest number of cards sharing one rank. | Easy2 | Hash mapImplementation | 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 |
| Bessie and DaisyGiven three points on a grid, compare Bessie's 8-direction distance with Daisy's 4-direction distance to John and say who arrives first. | Easy2 | MathGeometry+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Unraveling Monty HallCount how many of N trials hide the car behind door 2 or 3, since switching from door 1 wins exactly then. | Easy2 | MathSimulation+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 |
| Pizza DealCompare a slice's area per price with a whole pizza's pi*R1^2 per price and print the better deal. | Easy2 | MathGeometry+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Mixing MilkSimulate 100 cyclic pours among three buckets, each pour moving as much milk as fits until the source empties or the target fills, and print the final amounts. | Easy2 | SimulationImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| Winning ScoreGiven the counts of 3-point shots, 2-point field goals, and free throws for two teams, compute each team's total and report which team won or if the game tied. | Easy2 | MathImplementation | No attempts yet | 1s | 512 MB | Judgeable |
| Time to DecompressRead L lines, each with a count N and a character, and print that character repeated N times on its own line. | Easy2 | StringImplementation | No attempts yet | 1s | 512 MB | Judgeable |
| ElderTrack which wizard owns the Elder Wand after each duel and count how many distinct wizards ever held it. | Easy2 | SimulationImplementation+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 |
| Magnet ChainGiven up to 5 magnets as a 1/2 sequence, decide whether the chain is fully connected after at most one magnet flip. | Easy2 | ImplementationBrute force+2 | No attempts yet | 1s | 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 |
| Junseok's Math HomeworkFor each query value N, sum every positive multiple of 3 or 7 that does not exceed N. | Easy2 | MathImplementation | No attempts yet | 0.5s | 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 |
| Physics HomeworkFor each test case, find the time at which car A, starting slower than car B and accelerating, reaches or passes car B's constant speed. | Easy2 | MathImplementation+2 | No attempts yet | 1s | 256 MB | Judgeable |
| Card Factory (Small)One card is flipped a number of times; report the side showing after all flip orders, where the visible side never changes. | Easy2 | ImplementationMath | No attempts yet | 1s | 256 MB | Judgeable |
| Vending MachineGiven a sequence of vending machine button presses with fixed prices, subtract the total cost from 5000 won and print the change. | Easy2 | ImplementationMath+1 | No attempts yet | 1s | 256 MB | Judgeable |
| XORChicGiven an XOR-encrypted string whose first 8 characters decode to "CHICKENS", recover the key and output the original string. | Easy2 | ImplementationBit manipulation+2 | No attempts yet | 1s | 256 MB | Judgeable |
| 99 Bottles of BeerGiven N, print the full lyrics of the N Bottles of Beer song, with correct singular and plural wording. | Easy2 | ImplementationString+2 | No attempts yet | 1s | 512 MB | Judgeable |
| Cute Number~ε٩(๑> ₃ <)۶зGiven an integer up to 10^18, check whether its digits form an arithmetic sequence with a constant difference, and print one of two fixed messages. | Easy2 | ImplementationMath+2 | No attempts yet | 1s | 512 MB | Judgeable |