Problems
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Total results6,410 problems
| Title | Level | Topics | Solved | Time limit | Memory limit | Judge |
|---|---|---|---|---|---|---|
| What's the Second Baseman's NameGiven up to 1000 player names, check whether any name equals the string anj and print one of two fixed messages. | Easy2 | ImplementationString | No attempts yet | 1s | 512 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 |
| Bonus ScoreGiven a string of O and X for N problems, compute the total score where problem i gives i points plus a running bonus that grows on each O and resets on each X. | Easy2 | ImplementationSimulation+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Buying SnacksGiven price and weight for three snacks, print the name of the one whose 10-bag weight per discounted price is highest. | Easy2 | ImplementationMath+2 | No attempts yet | 1s | 1024 MB | Judgeable |
| N! mod P (1)Given N and a prime P larger than N, compute N! modulo P. | Easy2 | MathImplementation+2 | No attempts yet | 3s | 1024 MB | Judgeable |
| What Is a Recursive Function?Given N, print the chatbot message 'What is a recursive function?' repeated with nested quotation marks for N levels of recursion. | Easy2 | ImplementationString+1 | No attempts yet | 1s | 256 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 |
| Hour for a RunGiven laps V and signs per lap N, print the ceiling of V*N*i/10 signs for i = 1 through 9. | Easy2 | MathImplementation+1 | No attempts yet | 0.5s | 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 |
| BagsGiven n waste pieces with identifiers, find the minimum number of bags so that each bag holds pieces of only one identifier. | Easy2 | Hash mapImplementation+2 | No attempts yet | 1s | 512 MB | Judgeable |
| 369Count the total claps in the 369 game from 1 to N, where each number contributes one clap per digit that is 3, 6, or 9. | Easy2 | ImplementationMath+2 | No attempts yet | 1s | 512 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 |
| TrolGiven an array where A[i] is the digital root of i for i from 1 to 260, answer Q queries asking for the sum over a range [l, r]. | Easy2 | Prefix sumMath+1 | No attempts yet | 1s | 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 |
| CommandFor each of T strings, decide whether it has length 7 and its characters follow the exact pattern AABBABB with exactly two distinct letters. | Easy2 | StringImplementation+1 | No attempts yet | 0.5s | 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 |
| Simple Collatz SequenceSimulate the modified Collatz rule (halve even k, increment odd k) from n until reaching 1 and count the steps taken. | Easy2 | SimulationImplementation+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Regional Team NamesDecide whether a string splits into an institution part of 2 to 8 characters, a hyphen, then a team name of 1 to 24 characters. | Easy2 | StringImplementation | No attempts yet | 1s | 512 MB | Judgeable |
| Piece of Cake!Given a square cake of side n and thickness 4, two cuts at distances h and v from the top and left, find the largest piece's volume. | Easy2 | MathImplementation+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Mars WindowGiven a year between 2018 and 10000, decide whether a launch window occurs in it, where windows are 26 months apart starting April 2018. | Easy2 | MathImplementation | No attempts yet | 1s | 512 MB | Judgeable |
| Pea Soup and PancakesRead each restaurant's name and menu, then print the first one serving both pea soup and pancakes, or a fixed fallback line if none does. | Easy2 | ImplementationString+2 | 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 |
| ÖstgötskaCount how many space-separated words contain the substring "ae"; if that count is at least 40 percent of the words, print one fixed phrase, otherwise the other. | Easy2 | StringImplementation+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Hanging Out on the TerraceTrack how many people are on a terrace with a limit L and count how many enter groups are turned away because they would exceed it. | Easy2 | SimulationImplementation | No attempts yet | 1s | 512 MB | Judgeable |
| The Commuting GodGiven integers A and B where x^2 + 2Ax + B = 0 has integer roots, print the distinct roots in ascending order. | Easy2 | MathImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Even or Odd?Given n, decide whether the sum of any n consecutive positive integers is always even, always odd, or depends on the starting point. | Easy2 | MathImplementation+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Bullet SpeedGiven Cheolsu's running speed A and the bullet's speed B relative to him, print the bullet's speed toward the target, which is A + B. | Easy2 | MathImplementation | No attempts yet | 0.5s | 256 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 |
| Jazz EnthusiastAdd up the lengths of n songs, subtract the crossfade time once for each pair of adjacent songs, and print the total as hh:mm:ss. | Easy2 | MathImplementation+1 | No attempts yet | 2s | 512 MB | Judgeable |
| Arithmetic MagicGiven N, compute (x+1)(y+1) - x - y - xy for chosen numbers x and y, which simplifies to 1, and raise it to N. | Easy2 | MathImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| TapiokaGiven a three-word dish name, remove the words "bubble" and "tapioka", then print the remaining words or "nothing" if none remain. | Easy2 | StringImplementation | No attempts yet | 2s | 1024 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 |
| Frozen Ticket BookingGiven a theater with N rows and M seats per row numbered row by row, print the seat number of the fourth seat of row L, or -1 if row L has no fourth seat. | Easy2 | MathImplementation | No attempts yet | 1s | 512 MB | Judgeable |
| TimeCount how many clock times from 00:00:00 through N:59:59 contain the digit K at least once. | Easy2 | Brute forceImplementation+2 | No attempts yet | 1s | 256 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 |
| KABISAGiven a list of years separated by commas, print the leap years among them, separated by spaces. | Easy2 | MathImplementation | 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 |
| The Nearest Value to XGiven X, L, and R, print the integer in [L, R] whose absolute difference from X is smallest. | Easy2 | ImplementationMath | No attempts yet | 2s | 512 MB | Judgeable |
| CapitalizationReplace every occurrence of the substring "joi" in a lowercase string with "JOI" and print the result. | Easy2 | StringImplementation | 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 |
| BananaRead a dictionary mapping English words to Minionese words, then translate each of T sentences word by word. | Easy2 | Hash mapString+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Pokemon BuddyGiven a Pokemon group with a fixed distance per candy and starting and required candy counts, find the total kilometers to walk. | Easy2 | MathImplementation | No attempts yet | 2s | 512 MB | Judgeable |
| A Problem for Testing a New Regrade MethodRead two integers A and B, print their sum, then read N numbers and print them sorted in ascending order. | Easy2 | SortingImplementation | No attempts yet | 5s | 512 MB | Judgeable |
| Divisionals SpellingGiven n words and a contest with m questions labeled A onward, count how many words use only distinct letters from the first m letters. | Easy2 | ImplementationString+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Math Is an Online LectureGiven six integers defining two linear equations in two unknowns, solve the system and print the integer values of x and y. | Easy2 | MathImplementation | No attempts yet | 1s | 1024 MB | Judgeable |
| Frog 1Given target coordinates and a jump count, decide whether a frog starting at the origin can reach that cell in exactly that many unit grid jumps. | Easy2 | MathImplementation | No attempts yet | 1s | 256 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 |
| ABCD CodeFor each four-digit code, check whether the square of its first two digits plus the square of its last two digits leaves remainder 1 modulo 7. | Easy2 | MathImplementation+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Space PokerGiven fixed counts of red, green, and blue chips and two coefficients, pick which single chip color to add to maximize a quadratic payout formula. | Easy2 | Brute forceMath+2 | No attempts yet | 2s | 512 MB | Judgeable |
| RebusSplit the input into space-separated words, strip leading and trailing apostrophes by removing that many letters from each end, then concatenate the pieces. | Easy2 | StringImplementation | 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 |
| New Language CCGiven an integer n, print how many bits CC needs to store it after dropping leading zeros, with 0 stored in 1 bit. | Easy2 | Bit manipulationMath+1 | No attempts yet | 1s | 512 MB | Judgeable |
| Chess PuzzleGiven a knight's square on an 8x8 board, place a rook and a bishop so each attacks the knight, they do not attack each other, and the knight attacks neither. | Easy2 | Brute forceImplementation+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Santa ClausGiven two lists of children who already have presents, output the children from 1 to n who are missing from both lists. | Easy2 | ArrayImplementation+1 | No attempts yet | 2s | 512 MB | Judgeable |
| DivisorsGiven all proper divisors of an unknown number N, compute N using the fact that the smallest and largest proper divisors multiply to N. | Easy3 | MathNumber theory+1 | No attempts yet | 2s | 512 MB | Judgeable |
| LiesUsing union-find on party attendees, determine which parties can be exaggerated without conflicting with people who must always hear the truth. | Easy3 | Union-findGraph+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Tournament Meeting RoundSimulate a single-elimination tournament where positions are halved each round to find when two specific players first face each other. | Easy3 | SimulationMath+1 | No attempts yet | 1s | 512 MB | Judgeable |
| KingMove a king on an 8x8 board by given commands; if it lands on the stone, the stone slides one square the same way unless it would leave the board. | Easy3 | SimulationImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Leaf Nodes in a TreeGiven a tree by parent array, delete a node and all its descendants, then count how many leaf nodes remain. | Easy3 | TreeDFS+1 | No attempts yet | 2s | 128 MB | Judgeable |
| UnderprimeCount integers in a range whose total number of prime factors (with multiplicity) is itself a prime number. | Easy3 | Number theoryMath+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Josephus PermutationSimulate the Josephus elimination order for N people counting off every K-th person in a circle and print the removal sequence. | Easy3 | QueueSimulation+1 | No attempts yet | 2s | 256 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 |
| Strange MultiplicationGiven two large numbers as digit strings, compute the sum of all pairwise products of their digits, which equals the product of their digit sums. | Easy3 | MathString+1 | No attempts yet | 2s | 256 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 |
| Alphabet DiamondGiven a repeating diamond-pattern tile defined by N, print the characters inside a specified rectangular region of the infinite tiled plane. | Easy3 | SimulationMath+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Shortcut Key AssignmentAssign each menu option an unused shortcut letter by checking word-initial letters first, then any letter in the string, following the options in order. | Easy3 | SimulationString+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Lee-myeon and Im-hyeonClassify a number 1 to 2700 as Lee-myeon and/or Im-hyeon based on digit sum parity and prime factorization rules, then output one of four codes. | Easy3 | Number theoryImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| BestsellerGiven N book titles sold in a day, find the most frequent title, breaking ties by lexicographically smallest. | Easy3 | Hash mapSorting+1 | No attempts yet | 2s | 128 MB | Judgeable |
| D-DayCompute the number of days between two calendar dates accounting for leap years, printing 'gg' if the gap reaches 1000 years or more. | Easy3 | MathImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Decimal DigitSimulate long division of A by B to output the N-th digit after the decimal point. | Easy3 | SimulationMath+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Missed CallSimulate an album of N songs with 5-second gaps and a phone ringing every D seconds to find the first ring Kangto can actually hear. | Easy3 | SimulationImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Arithmetic ProgressionGiven a sequence S and starting value A0, find the smallest common difference d >= 0 of an arithmetic progression so that floor(A0+(i+1)d) equals S_i for every index. | Easy3 | MathImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Maze ConstructionSimulate a sequence of forward moves and turns on a grid, then print the smallest rectangular map marking visited cells as passable and the rest as walls. | Easy3 | SimulationImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| HockeyCount how many given points lie inside or on the boundary of a stadium shape formed by a rectangle and two semicircular ends. | Easy3 | GeometryImplementation | No attempts yet | 2s | 128 MB | Judgeable |
| Binary to Octal ConversionConvert a binary number with up to 1,000,000 digits into its octal representation. | Easy3 | Bit manipulationMath+2 | No attempts yet | 1s | 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 |
| Serial NumbersSort serial numbers by length, then digit-sum, then a custom lexicographic rule where digits precede letters. | Easy3 | SortingString+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 |
| I Am Pokemon Master DasomBuild a bidirectional mapping between Pokemon numbers and names, then answer up to 100,000 lookup queries either way. | Easy3 | Hash mapImplementation+1 | No attempts yet | 2s | 256 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 |
| Number of Trailing Zeros in a FactorialCount the trailing zeros of N! for N up to 500 by counting factors of 5. | Easy3 | MathNumber theory+1 | 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 |
| 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 |
| Prime PalindromeFind the smallest number greater than or equal to N that is both a prime and a palindrome. | Easy3 | MathBrute force+1 | No attempts yet | 2s | 256 MB | Judgeable |
| Number Word SortSort integers from M to N by comparing their digits spelled out as English words rather than by numeric value, then print 10 per line. | Easy3 | SortingString+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Extended Fibonacci NumbersCompute the sign and absolute value modulo 1e9 of the Fibonacci sequence extended to negative indices for a given n up to 1,000,000 in absolute value. | Easy3 | MathImplementation | 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 |
| Broken OdometerConvert an odometer reading that skips the digit 4 back into the real distance traveled, using a base-9-like digit mapping. | Easy3 | MathImplementation+1 | No attempts yet | 0.5s | 128 MB | Judgeable |
| TriangleGiven three points, classify the triangle they form as degenerate, equilateral, isosceles or scalene, and further by its largest angle type. | Easy3 | GeometryImplementation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Minimum HeapImplement a min-heap to support inserting natural numbers and repeatedly extracting the smallest, printing 0 when empty. | Easy3 | HeapImplementation | No attempts yet | 1s | 128 MB | Judgeable |
| Postfix Expression Evaluation 2Evaluate a postfix expression using given operand values and print the result rounded to two decimal places. | Easy3 | StackString+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 |
| DNAGiven N DNA strings of length M, construct the string minimizing total Hamming distance to all, breaking ties lexicographically, and output that distance. | Easy3 | StringGreedy+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Surprising StringFor each string, check for every gap size whether all pairs of letters at that fixed distance are distinct, and report if the string is 'surprising'. | Easy3 | StringBrute force+1 | 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 |