Problems
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Total results2,994 problems
| Title | Level | Topics | Solved | Time limit | Memory limit | Judge |
|---|---|---|---|---|---|---|
| Date Cycle CalculationFind the smallest year whose Earth, Sun, and Moon cycle counters, each resetting at fixed limits, match a given triple of values. | Easy3 | SimulationMath+1 | No attempts yet | 2s | 4 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 |
| Yongsik Goes to CampFor N bus schedules given by first departure, interval, and count, find the minimum wait until Yongsik can board any bus after arriving at time T, or -1 if none is available. | Easy3 | SimulationMath+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Youngsik and Friends' Ball TossSimulate a ball being passed clockwise or counterclockwise by L seats depending on parity of catch count, counting throws until someone catches it M times. | Easy3 | SimulationImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| DNA DecodingRepeatedly merge the last two bases of a DNA string using a fixed lookup table until one base remains, then output it. | Easy3 | SimulationString+1 | No attempts yet | 5s | 16 MB | Judgeable |
| Seongjun and ChocolateGiven chocolate and coffee doses with time-decaying effect radii, sum the positive radii (minimum 1) for each query time. | Easy3 | SimulationBrute force+2 | No attempts yet | 1s | 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 |
| CrosswordGiven a filled crossword grid, extract every maximal horizontal or vertical run of letters of length at least two and output the lexicographically smallest such word. | Easy3 | StringImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| CipherEncrypt a lowercase text by shifting each letter backward in the alphabet by the position value of a repeating key letter, leaving spaces unchanged but still consuming a key character. | Easy3 | StringSimulation+1 | No attempts yet | 2s | 256 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 |
| Multiple of ThreeGiven a huge number as a digit string, repeatedly sum its digits until one digit remains, then report how many steps it took and whether the number is divisible by 3. | Easy3 | StringMath+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 |
| CipherGiven an encrypted string built by zigzag row reading of a column-filled table, reconstruct the original string for a given number of columns. | Easy3 | SimulationMatrix+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Median FilterApply a 3x3 median filter over an image and count filtered pixels whose median value is at least a given threshold. | Easy3 | MatrixSorting+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Carbon CompoundsParse three molecules of C,H,O atoms and find coefficients 1 to 10 for each side that balance atom counts, lexicographically smallest. | Easy3 | Brute forceString+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Snail 2Simulate a snail-like spiral fill on an M by N grid and count how many times the path turns before every cell is visited. | Easy3 | SimulationMatrix+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Printer QueueSimulate a queue where documents are printed only when no higher-priority document remains, and find the print order of a specific document. | Easy3 | QueueSimulation | No attempts yet | 2s | 128 MB | Judgeable |
| MinesweeperGiven an N x N minesweeper grid with mine counts (possibly multi-mine cells), output each empty cell's summed adjacent mine count, capping at 'M' for 10+. | Easy3 | MatrixSimulation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| RoundingGiven an integer up to 99,999,999, repeatedly round its digits at increasing place values (tens, hundreds, etc.) using standard rounding rules and print the final result. | Easy3 | MathImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Text MessageSimulate typing a message on a numeric keypad, summing key press costs and extra wait times when consecutive characters share a key (except spaces). | Easy3 | SimulationString+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Card 1Simulate a queue where you discard the front card then rotate the next card to the back, printing the discard order and final survivor. | Easy3 | QueueSimulation | No attempts yet | 2s | 128 MB | Judgeable |
| Card 2Simulate the Josephus-style card elimination process to find which card number remains last for a given N. | Easy3 | QueueSimulation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| DNA Decoding 2Given a DNA string up to 20 million bases, repeatedly collapse the rightmost two characters using a lookup table until one base remains. | Easy3 | StringSimulation+1 | No attempts yet | 1s | 2 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 |
| Repeated SequenceSimulate a digit-power sequence until it cycles, then output how many distinct values appear before the repetition starts. | Easy3 | SimulationHash map+1 | No attempts yet | 2s | 256 MB | Judgeable |
| I Am the Class PresidentCompute total votes for three candidates and pick the winner using tie-break rules on 3-point then 2-point counts, or output 0 if still tied. | Easy3 | SimulationImplementation | No attempts yet | 1s | 128 MB | Judgeable |
| Four DiceGiven N sets of four dice rolls, compute each participant's prize by rules based on matching-face patterns and output the maximum prize. | Easy3 | ImplementationHash map+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Rice Cakes for the TigerGiven the day index D and Fibonacci-like combination coefficients, find starting values A and B (A ≤ B) so the D-th term equals K. | Easy3 | MathBrute force+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Number BaseballGiven N guesses with strike and ball counts in a number-baseball game, count how many three-distinct-digit numbers are consistent with all clues. | Easy3 | Brute forceSimulation | No attempts yet | 1s | 128 MB | Judgeable |
| Candy Doctor ChangyoungScan a character grid to count fixed 3-cell horizontal ('>o<') or vertical ('v/o/^') candy patterns. | Easy3 | MatrixImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Remainder Sequence CycleGiven N and P, simulate the sequence a_{i+1} = a_i*N mod P and output the length of the eventual repeating cycle. | Easy3 | SimulationHash map+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Asian Informatics OlympiadSort students by descending score and pick the top three medalists while capping each country to at most two medals. | Easy3 | SortingGreedy+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 |
| Card Game ScoreGiven five playing cards with color and number, compute a poker-like score by checking a fixed priority list of hand patterns. | Easy3 | SimulationImplementation+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 |
| Binary ClockConvert a given HH:MM:SS time into two 18-bit binary clock representations, read column-major-mixed 3-column and row-major 3-row layouts. | Easy3 | Bit manipulationImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| DartsFor each test case, sum dartboard scores from coordinates for two players and print the winner or a tie. | Easy3 | GeometrySimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Bicycle SpeedGiven wheel diameter, rotation count, and elapsed time per line, compute total distance in miles and average speed in mph until a zero-rotation terminator. | Easy3 | MathImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Window BlindsParse a grid of ASCII-drawn window blinds and count how many of the M×N windows show each of five possible blind heights. | Easy3 | SimulationImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Make a CrosswordBuild a grid where word A is placed horizontally and word B vertically, crossing at the first shared letter following a defined scan rule, filling the rest with dots. | Easy3 | StringImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Contest or InternshipGiven female and male student counts and a number who must leave for internship, decide who to remove to maximize teams of 2 females and 1 male each. | Easy3 | GreedyMath+1 | No attempts yet | 1s | 128 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 |
| 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 |
| Midpoint Displacement AlgorithmGiven N iterations of a midpoint-displacement grid subdivision starting from a square, compute the number of distinct grid points, which reduces to a closed-form formula based on the (2^N+1) x (2^N+1) grid size. | Easy3 | MathSimulation | No attempts yet | 1s | 128 MB | Judgeable |
| Machine CodeGiven a sequence of instructions with parameters, compute the minimum NOPs needed so each instruction starts at an address divisible by 4. | Easy3 | GreedySimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Rock-Paper-Scissors ScoreGiven a player's rock-paper-scissors choices against several friends over multiple rounds, compute the actual score and the best possible score with foreknowledge each round. | Easy3 | SimulationGreedy+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Sieve of EratosthenesSimulate the Sieve of Eratosthenes and output which number gets crossed out on the K-th removal step. | Easy3 | SimulationMath | No attempts yet | 1s | 128 MB | Judgeable |
| Truck Parking FeesGiven per-truck rates depending on how many of three trucks overlap in time, compute the total parking fee over discrete minute intervals. | Easy3 | SimulationImplementation | No attempts yet | 1s | 128 MB | Judgeable |
| Road and Traffic LightsSimulate a truck moving at 1 m/s along a road with traffic lights that cycle red then green, waiting at reds, and output total travel time to the end. | Easy3 | SimulationImplementation | No attempts yet | 1s | 128 MB | Judgeable |
| Pascal Loop OutputGiven N up to 1e9, simulate finding the largest divisor of N smaller than N by scanning downward, and output how many steps that takes without brute force. | Easy3 | MathNumber theory+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Aggressive DogsGiven two dogs' attack/rest cycle lengths, determine for three given minute timestamps how many dogs are attacking at that minute. | Easy3 | MathSimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Lexicographically Smallest Crossword WordExtract all horizontal and vertical maximal letter sequences of length at least 2 from a grid and output the lexicographically smallest one. | Easy3 | StringImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Lunch WarningsGiven a sequence of children taking food, count how many times a child's total pieces so far exceed all other children's combined total before their next pick. | Easy3 | Hash mapSimulation | 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 |
| Marathon Tic-Tac-ToeScan an N by N board to find if any letter forms three consecutive equal marks in a row, column, or diagonal, and print that letter or 'ongoing'. | Easy3 | MatrixSimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Flag RecognitionGiven a 6x9 letter grid, compute the minimum edits needed to make it a valid three-stripe flag, either horizontal (2-row bands) or vertical (3-column bands) with the middle band's color differing from both outer bands. | Easy3 | Brute forceImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Worm TurnsGiven an M by N grid eaten in a clockwise spiral, compute how many times the direction changes before the whole grid is consumed. | Easy3 | MathSimulation | No attempts yet | 1s | 128 MB | Judgeable |
| PizzaGiven each friend's pizza appetite of 1/4, 1/2, or 3/4, compute the minimum number of whole pizzas needed to serve exact slices to all. | Easy3 | GreedyMath+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Phone BillGiven N calls with a start time and duration under 60 minutes, sum the cost by charging 10 won per minute in 07:00-19:00 and 5 won otherwise, splitting calls that cross the boundary. | Easy3 | SimulationImplementation | No attempts yet | 1s | 128 MB | Judgeable |
| LukaSimulate a walker's path on a grid and output every time step when the walker is within Chebyshev distance 1 of a fixed point. | Easy3 | SimulationArray | No attempts yet | 1s | 128 MB | Judgeable |
| ComportFind the smallest step size K (1 to N) so repeatedly moving K fields clockwise from field 1 reaches field Z without landing on any obstacle field along the way. | Easy3 | SimulationBrute force+1 | No attempts yet | 1s | 128 MB | Judgeable |
| DollarsSimulate converting between dollars and marks daily using given rates to maximize final dollar amount, truncated to two decimals. | Easy3 | GreedySimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Hotel Room AssignmentSimulate assigning arriving groups to hotel rooms with two beds each, filling empty rooms first then pairing singles, and output the final occupancy per room. | Easy3 | SimulationQueue+1 | No attempts yet | 1s | 128 MB | Judgeable |
| DECODEBuild a substitution cipher table from a key word placed at a given offset, then decode a given ciphertext using it. | Easy3 | StringSimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Hal's CalculatorSimulate a stack-like list of expressions under six commands (HASH, DOLLAR, SWAP, DROP, DUP, ROT), enforcing size and availability constraints, and output the final list or ERROR. | Easy3 | StackSimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| N-QueensGiven N, print a specific N-queens placement built by a fixed construction rule based on N mod 6, rather than searching for any valid solution. | Easy3 | MathImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| DartsFor each dart throw coordinate, determine the score based on concentric circle radius bands and sum the scores per test case. | Easy3 | MathImplementation+1 | No attempts yet | 1s | 256 MB | Judgeable |
| GameGiven many filled 5x5 tic-tac-toe boards, determine for each whether A, B, or neither has three consecutive same marbles in a row, column, or diagonal. | Easy3 | MatrixSimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Reaux! Sham! Beaux!Parse rock-paper-scissors rounds given in multiple languages per player, tally wins, and print each game's score and winner. | Easy3 | StringHash map+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Easy TaskProcess a list of contest submissions to compute, for each of nine problems, the number of teams that solved it and the average submissions and solve time. | Easy3 | Hash mapSimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| GatesGiven an acyclic NAND-gate circuit whose inputs are all tied to one variable x, decide whether the overall output depends on x (answer 1) or is constant (answer 0). | Easy3 | SimulationGraph+1 | No attempts yet | 1s | 128 MB | Judgeable |
| HotlineAnswer yes, no, or maybe questions about one-word subjects and verb-object activities using the statements heard earlier in each dialogue. | Easy3 | Hash mapSimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Building for the UNPrint a fixed two-floor n by n grid where the lower floor's rows and upper floor's columns each represent a labeled country, satisfying a connectivity and adjacency construction. | Easy3 | ImplementationSimulation+1 | No attempts yet | 3s | 128 MB | Judgeable |
| Water Main BreakGiven several water main breaks with start, end, and flow rate, sum the gallons leaked during each second of a given query interval. | Easy3 | ArraySimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Roots IntervalsGiven interval [a,b] split into nb equal subintervals, count subintervals where f(x)=1-x^2 has a sign change or zero at endpoints. | Easy3 | ImplementationSimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Count on CantorFor given indices n, find the n-th fraction a/b in Cantor's diagonal enumeration of positive rationals and print it in a fixed format. | Easy3 | MathImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Mowing the LawnDetermine if sorted mower path coordinates with a given strip width fully cover a 75x100 rectangle in both directions, across multiple test cases until a terminator line. | Easy3 | SortingSimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Working at the RestaurantSimulate a two-pile plate stacking strategy that always drops on pile 2 and serves from pile 1, moving plates when pile 1 runs out, and output the exact operation transcript. | Easy3 | StackSimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Gray AreaCompute weighted ink used by a histogram where each bar contributes its normalized height times a linearly decreasing darkness, plus a fixed constant. | Easy3 | ArraySimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| And Then There Was OneSimulate a Josephus-style circle elimination game with a custom starting removal point and report the last remaining stone for each test case. | Easy3 | SimulationQueue+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Unreliable MessengersGiven a sequence of reversible string transformations and the final message, undo each transformation in reverse order to recover the original message. | Easy3 | StringSimulation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Hailstone SequenceFor each of up to 100,000 starting values, simulate the Collatz sequence until it reaches 1 and report the maximum value seen. | Easy3 | SimulationImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Roll CakeGiven N interval requests over pieces 1..L, find the member with the largest requested length, then the member who actually receives the most pieces when earlier requests get priority. | Easy3 | SimulationArray+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Chain of FoolsGiven sprocket prongs, chain links, and start positions of a broken prong and bent link, find when they first meet at location 0, printing revolutions and fraction or Never. | Easy3 | MathNumber theory+2 | No attempts yet | 1s | 128 MB | Judgeable |
| WindowsGiven windows in opening order, answer clicks by returning the most recently opened window covering each click point, or background if none does. | Easy3 | ArrayBrute force+2 | No attempts yet | 1s | 128 MB | Judgeable |
| LCRSimulate the dice game LCR turn by turn with the given rolls, then print the final chip counts for each player and the center. | Easy3 | SimulationImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Snakes and LaddersSimulate a Snakes and Ladders game with a players and a list of die rolls, applying snakes and ladders after each move, and print each token's final square. | Easy3 | SimulationImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| To and FroDecode a message written row by row in alternating left-to-right and right-to-left order back into column-major plaintext. | Easy3 | StringSimulation+2 | No attempts yet | 1s | 128 MB | Judgeable |
| Ferry Loading IVSimulate a ferry of given length that repeatedly crosses between two banks, loading waiting cars in arrival order. | Easy3 | SimulationQueue | No attempts yet | 1s | 128 MB | Judgeable |
| Word RatiosFor each line of three equal-length lowercase words, apply the per-letter alphabet shift from the first word to the second onto the third, and output all four words. | Easy3 | StringImplementation+2 | No attempts yet | 1s | 128 MB | Judgeable |
| Traditional BINGOFor each card, find how many announced numbers are needed before some row, column, or diagonal of five spaces is fully marked, with the center free. | Easy3 | SimulationArray+2 | No attempts yet | 1s | 128 MB | Judgeable |
| Stack 'em UpApply a sequence of fixed 52-card permutation shuffles to a new deck, printing the deck after each shuffle. | Easy3 | SimulationImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Average SpeedTrack a car's speed changes over time and answer queries asking the total distance travelled up to a given elapsed time. | Easy3 | SimulationImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Carry CountFor each pair of non-negative integers, count how many carries occur while adding them column by column from the right. Stop at the 0 0 line. | Easy3 | ImplementationMath+1 | No attempts yet | 1s | 128 MB | Judgeable |
| MinesweeperGiven an n×n mine layout and which cells are currently opened, print the board: mine counts for opened safe cells, asterisks for all mines if any mine was opened, and dots elsewhere. | Easy3 | SimulationImplementation+1 | No attempts yet | 1s | 128 MB | Judgeable |
| The Elf's SwordFor each input n, find the smallest k such that the digits 0 through 9 all appear across the multiples n, 2n, ..., kn. | Easy3 | ImplementationSimulation+2 | No attempts yet | 1s | 128 MB | Judgeable |
| ROT13Decode lines of text by reversing the ROT13 cipher: each vowel shifts three places back in a fixed vowel order, each consonant ten back in a consonant order. | Easy3 | ImplementationString+2 | No attempts yet | 1s | 128 MB | Judgeable |
| Tales from DeCryptRead three LCG parameters, then walk the ciphertext byte by byte, advancing the generator only on printable ASCII, and apply the inverse rotation to each such byte. | Easy3 | SimulationMath+2 | No attempts yet | 1s | 128 MB | Judgeable |