Problems
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Total results14,366 problems
| Topics | Judge | |||||
|---|---|---|---|---|---|---|
| Ship SelectionCount the ships whose fuel covers consumption times the integer-division travel time for the given distance. | Easy1 | ImplementationMath | No attempts yet | 1s | 256 MB | Judgeable |
| Acid and BaseCompute the pH from each given H+ or OH- concentration with the log formulas and print it rounded to two decimals. | Easy1 | MathImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Golden Ratio TestGiven T pairs of numbers, print golden for each pair whose ratio a/b is within 1 percent of the golden ratio. | Easy1 | ImplementationMath | No attempts yet | 1s | 256 MB | Judgeable |
| QuadrilateralPrint a solid rectangle of X letters for each given width and height, separating consecutive outputs with a blank line. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Print HookPrint the word Hook as fixed ASCII art with no input. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| AcronymsGiven an acronym and candidate phrases, print the phrases whose word initials match the acronym letters in order. | Easy1 | StringImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Longest Run of X'sCount the longest run of consecutive X marks in each hallway and print its length in the required sentence. | Easy1 | Array | No attempts yet | 1s | 256 MB | Judgeable |
| Count VowelsCount the vowels a, e, i, o, and u in each given lowercase word and print the result in the required sentence. | Easy1 | String | No attempts yet | 1s | 256 MB | Judgeable |
| Heracles and the HydraStarting from h heads, each c adds one head and each b removes one, and you report the count left after all actions. | Easy1 | Simulation | No attempts yet | 1s | 256 MB | Judgeable |
| MysteryPrint Yonsei on one line with no input. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| BaseballSum both teams runs over nine innings for each test case and print the higher scorer or Draw. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Meat on the GrillPrint each input row reversed to mirror the whole hotplate left to right. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| ACM HotelGuests fill rooms column by column from the elevator with lower floors first, so print the room number of the Nth guest. | Easy1 | Math | No attempts yet | 1s | 256 MB | Judgeable |
| Golden Khon KaenCount how many times the word GOLDEN can be formed from each given string of capital letters. | Easy1 | Hash map | No attempts yet | 10s | 64 MB | Judgeable |
| Reverse RotReverse each message, then shift every character forward by N places in the 28-symbol alphabet. | Easy1 | StringSimulation | No attempts yet | 1s | 256 MB | Judgeable |
| Automated Checking MachineCheck two five-point connectors and print Y only when each position pairs a plug with an outlet. | Easy1 | Implementation | No attempts yet | 3s | 256 MB | Judgeable |
| The fellowship of the ringCount how many of the P punch heights fall within the fair range from waist height W to neck height N. | Easy1 | Array | No attempts yet | 1s | 256 MB | Judgeable |
| ServerCount how many jobs from the front finish in request order before their total duration exceeds T. | Easy1 | Prefix sumSimulation | No attempts yet | 1s | 256 MB | Judgeable |
| Mod ArithmeticGiven A, B and C, print (A+B)%C, ((A%C)+(B%C))%C, (AxB)%C and ((A%C)x(B%C))%C on four lines. | Easy1 | Math | No attempts yet | 1s | 256 MB | Judgeable |
| Do you like fractions?Convert each fraction to a mixed number by printing the quotient, the remainder, and the original denominator without reducing. | Easy1 | ImplementationMath | No attempts yet | 2s | 256 MB | Judgeable |
| OdditiesGiven up to 20 integers, print whether each one is odd or even. | Easy1 | Implementation | No attempts yet | 2s | 256 MB | Judgeable |
| Quite a problemPrint yes for each input line that contains problem in any capitalization, even inside longer words, and no otherwise. | Easy1 | String matchingString | No attempts yet | 2s | 256 MB | Judgeable |
| Ragged RightGiven the lines of a paragraph, find the longest line length and print the sum of squared differences for every line except the last. | Easy1 | Implementation | No attempts yet | 2s | 256 MB | Judgeable |
| Subin and the SequenceGiven the prefix averages of a sequence, recover the original sequence term by term. | Easy1 | Prefix sumMath | No attempts yet | 1s | 32 MB | Judgeable |
| Mosquito TrapFind the smallest area of an axis-aligned square that covers all given points on the table. | Easy1 | Geometry | No attempts yet | 1s | 32 MB | Judgeable |
| Keystrokes per FingerCount how many times each of the eight fingers presses a key when the given string is typed on the fixed US layout. | Easy1 | ImplementationArray | No attempts yet | 1s | 32 MB | Judgeable |
| PolyhedronFor each test case, compute the face count of a convex polyhedron from V and E with Euler formula F = 2 - V + E. | Easy1 | Math | No attempts yet | 5s | 256 MB | Judgeable |
| Magic ChessboardFlip each even row and then each even column exactly as specified to turn the n by m chessboard into a single color. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Kings of PersiaGiven birth and death year ranges, compute the smallest and largest possible age for each king. | Easy1 | Math | No attempts yet | 2s | 256 MB | Judgeable |
| DaliaDecide for each test case whether a knight moves from the start square to the target square in exactly one legal move. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Omar's addition and subtraction checkCheck up to 100 equations of the form X + Y = Z or X - Y = Z and print YES or NO for each case. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Water BillCompute the bills of companies X and Y from the given usage and output the cheaper one. | Easy1 | ImplementationMath | No attempts yet | 1s | 256 MB | Judgeable |
| Christmas PartyTally each friend's score over M guessing games from the targets and the written names. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| We love kriiiPrint the fixed Korean phrase 강한친구 대한육군 on two lines with no input. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| A Special DayCompare the given month and day against February 18 and print Before, After, or Special. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Happy or SadCount the happy (:-)) and sad (:-( ) emoticons in the message and print happy, sad, unsure, or none. | Easy1 | String | No attempts yet | 1s | 256 MB | Judgeable |
| Traffic Day BanCount how many of the five given car number digits match the date digit. | Easy1 | ImplementationArray | No attempts yet | 1s | 256 MB | Judgeable |
| Vertical ReadingRead five given words column by column from top to bottom, skipping missing letters in shorter words, and print the letters in that order. | Easy1 | SimulationArray+1 | No attempts yet | 1s | 256 MB | Judgeable |
| Card GameCompare the ten cards of A and B round by round and print A or B for the side with more round wins, or D on a tie. | Easy1 | ArraySimulation | No attempts yet | 1s | 256 MB | Judgeable |
| Reversing Card SegmentsReverse ten given segments of a 20-card row that starts in order and print the final arrangement. | Easy1 | ArraySimulation | No attempts yet | 1s | 256 MB | Judgeable |
| Count ValueCount how many times the integer v appears among the N given integers. | Easy1 | Array | No attempts yet | 1s | 256 MB | Judgeable |
| Alphabet CountCount how many times each letter from a to z appears in the given lowercase word. | Easy1 | Array | No attempts yet | 1s | 256 MB | Judgeable |
| Find the AlphabetGiven a lowercase word of length at most 100, output the 0-based first index of each letter a to z, or -1 when absent. | Easy1 | ArrayString | No attempts yet | 1s | 256 MB | Judgeable |
| Insert BallsFill N baskets by writing ball number k into baskets i through j for each operation, then print all baskets. | Easy1 | ArraySimulation | No attempts yet | 1s | 256 MB | Judgeable |
| Swap BallsSwap the balls in the given basket pairs M times and print the final ball in each of the N baskets. | Easy1 | SimulationArray | No attempts yet | 1s | 256 MB | Judgeable |
| Three NumbersPrint the median of three given integers between 1 and 100. | Easy1 | Sorting | No attempts yet | 1s | 256 MB | Judgeable |
| Minimum and MaximumRead N integers and print the smallest and the largest separated by a space. | Easy1 | Array | No attempts yet | 1s | 256 MB | Judgeable |
| String analysisCount the lowercase letters, uppercase letters, digits, and spaces in each input line until end of input. | Easy1 | StringImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Comma Integer CountCount the maximal runs of digits in a comma-separated digit string. | Easy1 | String | No attempts yet | 1s | 256 MB | Judgeable |
| Comma Sum MultilineJoin the input lines into one comma-separated string, split it at commas, and print the sum of the numbers. | Easy1 | ImplementationString | No attempts yet | 1s | 256 MB | Judgeable |
| Binary ConversionPrint the binary representation of the given natural number N with no leading zeros. | Easy1 | Bit manipulation | No attempts yet | 1s | 256 MB | Judgeable |
| ApplesEach school splits its apples evenly among its students, and the program sums the leftover apples. | Easy1 | Math | No attempts yet | 1s | 256 MB | Judgeable |
| Rock paper scissorsRead the past rounds and print 0 when there are none, 2 when the opponent last threw rock, and 0 otherwise. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Extreme SortCheck whether the given numbers are in non-decreasing order and print yes or no. | Easy1 | ArraySorting | No attempts yet | 1s | 256 MB | Judgeable |
| Friend countsCount the friends of each of N students from M mutual friendship pairs and print the N totals in order. | Easy1 | GraphImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Basic arithmeticPrint the sum, difference, product, quotient, and remainder of two given natural numbers. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| The nth Fibonacci NumberGiven n up to 20, compute the nth Fibonacci number defined from 0 and 1. | Easy1 | Dynamic programmingRecursion | No attempts yet | 1s | 256 MB | Judgeable |
| Numbers Smaller Than XPrint the elements of the sequence that are smaller than X in their original order. | Easy1 | Array | No attempts yet | 1s | 256 MB | Judgeable |
| FactorialPrint the factorial of a given integer N, where N is between 0 and 12. | Easy1 | MathImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Professor Lee's ExamPrint the numbers of students whose ten answers exactly match 1, 2, 3, 4, 5, 1, 2, 3, 4, 5 in order. | Easy1 | ImplementationArray | No attempts yet | 1s | 256 MB | Judgeable |
| 0 = not cute / 1 = cuteCount the 0 and 1 votes and print whether Junhee is cute based on the majority. | Easy1 | ImplementationArray | No attempts yet | 1s | 2 MB | Judgeable |
| Ancient symbolGiven integer x, print 111 times x squared plus 11 times x plus 1. | Easy1 | Math | No attempts yet | 1s | 2 MB | Judgeable |
| Penalty calculationFind the earliest submission with the highest score and compute the penalty from its time and attempt count. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| N-orthotopeGiven two axis-aligned boxes in N dimensions, print the dimension of their overlap, or -1 when they do not meet. | Easy1 | ImplementationGeometry | No attempts yet | 1s | 256 MB | Judgeable |
| ??!Print the given id with ??! appended to it. | Easy1 | String | No attempts yet | 1s | 256 MB | Judgeable |
| SHA-224Print the 56-digit lowercase hexadecimal SHA-224 hash of the given alphanumeric string. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| SHA-384Read an alphanumeric string and print its SHA-384 hash as 96 lowercase hex digits. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| SHA-512Print the SHA-512 hash of an alphanumeric string up to 50 characters long as lowercase hexadecimal. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| BASE16 EncodingRead a string of up to 50 letters and digits and print each character as two uppercase hex digits in order. | Easy1 | ImplementationString | No attempts yet | 1s | 256 MB | Judgeable |
| BASE16 DecodingDecode a BASE16 string by converting each pair of hex digits back into its ASCII character. | Easy1 | StringImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Random gamePrint the integer 5 on the first line with no input. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Random gamePrint the number 1 on one line with no input. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Random gamePrint 1, the smallest integer from 1 to 2,147,483,647, with no input. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| LottoPrint 1 2 3 4 5 6, the lexicographically smallest increasing pick of six numbers from 1 to 45. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Daily lottoPrint 1 2 3 4 5 6, the lexicographically smallest increasing six-number sequence from 1 to 45. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Number baseball 5Print the fixed number 1234 with no input. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| A+B with multiple test casesRead T pairs of integers and print each pair's sum on its own line. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| A+B until end of inputRead pairs of integers until end of input and print each pair sum on its own line. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| A+B until two zerosRead integer pairs until 0 0 and print the sum of each pair on its own line. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Comma-separated A+BAdd pairs of single-digit integers given as comma-separated values for each test case. | Easy1 | ImplementationMath | No attempts yet | 1s | 256 MB | Judgeable |
| Compute my GPACompute each semester total credits and credit-weighted GPA from course credits and grades, rounded to one decimal place. | Easy1 | MathImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Vowel CountCount how many letters of the given lowercase word are vowels (a, e, i, o, u). | Easy1 | StringImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Palindrome CheckCheck whether the given lowercase word reads the same forward and backward and print 1 or 0. | Easy1 | StringTwo pointers | No attempts yet | 1s | 256 MB | Judgeable |
| Star Pattern 17Print a hollow isosceles triangle of height N, with stars on the two sides and a solid star base. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Star Pattern 21Print the star pattern for the given N exactly as the samples show. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| A×BRead two integers A and B and print their product. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Namuk's Chicken CoopFrom the total number of legs and chickens, find how many chickens lost a leg and how many are intact. | Easy1 | Math | No attempts yet | 2s | 256 MB | Judgeable |
| A+B for each test caseAdd two single-digit integers per test case and print each sum as Case #x: y. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| A+B with case numbersRead T pairs of single-digit integers and print each sum as Case #x: A + B = C. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Sum of the Numbers on One LineAdd all the space-separated numbers on the first line and print the total. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Sum 4Add the integers on each of T input lines and print each sum on its own line. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Use Every LetterDecide for each of up to 50 sentences whether it contains every letter a to z, and list the missing letters otherwise. | Easy1 | StringArray | No attempts yet | 2s | 256 MB | Judgeable |
| Simon SaysPrint the trailing part of every command that starts with 'Simon says' and skip all other commands. | Easy1 | StringImplementation | No attempts yet | 2s | 256 MB | Judgeable |
| Help Chelsea!For each test case, print the name of the player with the highest price from the given list. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| Fridge of Your DreamsConvert each of up to 1000 24-bit binary strings to its decimal form without leading zeros. | Easy1 | Implementation | No attempts yet | 1s | 256 MB | Judgeable |
| The Eccentric ProfessorCompare n times s against d plus n times p for each test case and print which option costs less. | Easy1 | MathImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Communication ChannelsCompare each transmitted binary string with its received copy and print OK when they match and ERROR otherwise. | Easy1 | StringImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Balancing WeightsYou sum the signed positions of the weights and report whether the lever tips left, tips right, or stays balanced. | Easy1 | ImplementationMath | No attempts yet | 1s | 256 MB | Judgeable |
| Cookie LoverGiven N cookies and C eaten per day, compute how many days pass until none remain. | Easy1 | MathImplementation | No attempts yet | 1s | 256 MB | Judgeable |
| Angry Grammar SticklerThe program counts banned words and phrases in each sentence and prints ten times that count. | Easy1 | StringImplementation | No attempts yet | 1s | 256 MB | Judgeable |