Problems

Pick a problem and write your solution in the built-in editor. The judge runs it against real test cases while you watch, and the wider archive is open to read whenever you like.

Total results6,365 problems

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
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
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
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
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
IT Passport Examination GradingAdd each applicant's three field scores and mark PASS only when the total reaches 55 and every field meets its 30 percent cutoff.	Easy1	Implementation	No attempts yet	2s	256 MB	Judgeable
Thai Lottery Prize CheckGiven the winning numbers and prize amounts for six Thai lottery categories, compute the total prize for each ticket by adding every matched category.	Easy1	StringImplementation	No attempts yet	2s	256 MB	Judgeable
Logical Functions: AND and ORCheck each submitted weight and bias by testing all four binary inputs and report whether the neuron matches the requested AND or OR gate.	Easy1	SimulationImplementation	No attempts yet	2s	256 MB	Judgeable
Cryptographer's ConundrumCount the positions where the given string differs from PER repeated to the same length.	Easy1	StringImplementation	No attempts yet	1s	256 MB	Judgeable
Hangul SyllablesGiven N between 1 and 11172, print the N-th Hangul syllable in initial, medial, then final order.	Easy1	MathImplementation	No attempts yet	1s	256 MB	Judgeable
The Tallest StudentPrint the name of the tallest student in each test case, listing every tied name in input order.	Easy1	Implementation	No attempts yet	1s	256 MB	Judgeable
Pedometer DistanceMultiply each step count by the stride length and print each distance in kilometres with five decimals.	Easy1	ImplementationMath	No attempts yet	1s	256 MB	Judgeable
Count Me InCount the vowels and consonants in each of up to 100 given English sentences.	Easy1	StringImplementation	No attempts yet	1s	256 MB	Judgeable
Report Card TimeConvert each hobbit's numeric score to a letter grade using the given scale and print the results in input order.	Easy1	Implementation	No attempts yet	1s	256 MB	Judgeable
The Image Stretched Twice as WideCheck whether doubling every character of the first picture sideways produces the second picture.	Easy1	ImplementationString	No attempts yet	1s	512 MB	Judgeable
And Then There Was 5For each query offset into pi and target digit, you print the next matching digit and the 5 after it.	Easy1	Implementation	No attempts yet	1s	256 MB	Judgeable
Identifying teaCount how many of the five contestants guessed the given tea type correctly.	Easy1	Implementation	No attempts yet	3s	256 MB	Judgeable
Yangjojang of The YearFor each test case, print the name of the school with the largest alcohol amount.	Easy1	Implementation	No attempts yet	1s	256 MB	Judgeable
Affine CipherApply E(X) = (aX + b) mod 26 to each uppercase letter of the plaintext and print the ciphertext.	Easy1	ImplementationString+1	No attempts yet	5s	256 MB	Judgeable
The Princess and the Magic MirrorPrint an N by N picture unchanged, mirrored left to right, or flipped top to bottom according to the given mood number.	Easy1	MatrixImplementation	No attempts yet	2s	256 MB	Judgeable
Popularity VoteFor each poll, find the candidate with the most votes and report whether the top count is a majority, a minority, or tied.	Easy1	ImplementationArray	No attempts yet	2s	256 MB	Judgeable
PersistenceCount how many times multiplying the decimal digits together reduces the given number to a single digit.	Easy1	SimulationImplementation	No attempts yet	1s	256 MB	Judgeable
ASCII CodePrint the ASCII code of the given letter or digit.	Easy1	Implementation	No attempts yet	1s	256 MB	Judgeable
ROT13Encrypt the given string with ROT13, shifting each English letter by 13 places and leaving other characters unchanged.	Easy1	StringImplementation	No attempts yet	1s	256 MB	Judgeable
Print the input as isRead all input lines and print them unchanged in the same order.	Easy1	Implementation	No attempts yet	1s	256 MB	Judgeable
Echo the Input 2Print every input line unchanged, preserving blank lines and leading and trailing spaces.	Easy1	Implementation	No attempts yet	1s	256 MB	Judgeable
Sum of digitsAdd N digits given as a single unspaced line and print their sum.	Easy1	ImplementationString	No attempts yet	1s	256 MB	Judgeable
Print ten characters per linePrint the given word in chunks of ten characters, one chunk per line.	Easy1	StringImplementation	No attempts yet	1s	256 MB	Judgeable
EssayPrint B distinct words formed by mapping the decimal digits of 0 to B-1 to letters a to j.	Easy1	ImplementationString	No attempts yet	1s	64 MB	Judgeable
TawlaFor each pair of dice rolls, print the combined nickname with the larger value first, using special names for doubles and for 5 and 6.	Easy1	Implementation	No attempts yet	3s	256 MB	Judgeable
Reading numbers in 0.1 secondsRead up to five million natural numbers within 0.1 seconds and print how many were read and their sum.	Easy1	Implementation	No attempts yet	0.1s	512 MB	Judgeable
Valentine's DayIgnore any input and print nothing to standard output.	Easy1	Implementation	No attempts yet	2s	512 MB	Judgeable
Korea University is lovePrint the fixed Korean string 고려대학교 on one line with no input.	Easy1	Implementation	No attempts yet	1s	32 MB	Judgeable
NNRepeat the decimal form of N exactly N times and print at most its first M characters.	Easy1	ImplementationString	No attempts yet	1s	32 MB	Judgeable
Hot fish-shaped bunPrint the given N by M binary picture mirrored left to right.	Easy1	MatrixImplementation	No attempts yet	1s	32 MB	Judgeable
First SubmissionIgnore any input and print nothing except optional spaces or line breaks.	Easy1	Implementation	No attempts yet	1s	512 MB	Judgeable
Last submissionSubmit a program that ignores any input and produces no output.	Easy1	Implementation	No attempts yet	1s	512 MB	Judgeable
Midpoint SubmissionIgnore any input and print nothing, since the empty output is the required answer.	Easy1	Implementation	No attempts yet	1s	512 MB	Judgeable
Evolving EeveePrint Flareon, the alphabetically first of the three evolution names, regardless of the given level.	Easy1	Implementation	No attempts yet	1s	512 MB	Judgeable
Pokemon GO EvolutionGiven a Pokemon number from 1 to 151, print its evolution candy cost from the table, or -1 when it does not evolve.	Easy1	ArrayImplementation	No attempts yet	1s	512 MB	Judgeable
MD5 scoreConcatenate S, #, and P, hash the result with MD5, and print the sum of the hex digits.	Easy1	Implementation	No attempts yet	1s	512 MB	Judgeable
The slowest sudokuPrint the given nine by nine Sudoku grid exactly, using zeros for empty cells.	Easy1	Implementation	No attempts yet	1s	512 MB	Judgeable
1 and 2Print 1 without reading input, as the fixed answer is the smaller allowed number.	Easy1	Implementation	No attempts yet	1s	512 MB	Judgeable
Nunchi gamePrint the largest allowed integer, 100000, since there is no input and the score equals the printed number.	Easy1	Implementation	No attempts yet	1s	512 MB	Judgeable
Magic TrickFind the card shared by the chosen rows of two 4 by 4 layouts, or report a bad layout or cheating.	Easy1	ArrayImplementation	No attempts yet	5s	512 MB	Judgeable
Rulers of Centauri PrimeGiven T country names, report for each whether a king, a queen, or nobody rules it from its last letter.	Easy1	StringImplementation	No attempts yet	5s	512 MB	Judgeable
Rulers of Centauri PrimeGiven T country names, print for each whether its last letter marks a king, a queen, or nobody.	Easy1	StringImplementation	No attempts yet	5s	512 MB	Judgeable
KBO Korean Series Champion NumberGiven the Korean name of a KBO team that won the Korean Series, print the number assigned to that team.	Easy1	ImplementationString+1	No attempts yet	2s	512 MB	Judgeable
HicCupGiven N, add 10N, 10N+10, and 20N+20, then print the total.	Easy1	MathImplementation	No attempts yet	1s	32 MB	Judgeable
George BooleRead one boolean operation in the form true AND false and print its result.	Easy1	ImplementationString+2	No attempts yet	2s	512 MB	Judgeable
Hands are faster than computersPrint a fixed 4-vertex, 5-edge graph and a fixed proper 4-coloring, with no input to read.	Easy1	ImplementationGraph	No attempts yet	2s	512 MB	Judgeable
Will floats still pass?Print a fixed two-point set, (0, 0) and (1, 1), with no input; the answer is a constant output.	Easy1	ImplementationGeometry	No attempts yet	2s	512 MB	Judgeable
A debugging life that starts with std::sortPrint N = 2 and the two points (1, 0) and (0, 1), a fixed counterexample for a broken comparator in std::sort.	Easy1	ImplementationSorting+2	No attempts yet	2s	512 MB	Judgeable
Is Dinic quartic?Print a fixed 4-vertex, 5-edge flow network with the exact edges and capacities given in the statement.	Easy1	GraphImplementation+1	No attempts yet	2s	512 MB	Judgeable
Hamming DistanceRead two n-dimensional integer vectors and count the positions where their entries differ.	Easy1	ImplementationArray	No attempts yet	1s	256 MB	Judgeable
Java2016Given a target constant c, print 20 fixed macro definitions and then build one expression by appending a macro for each set bit of c.	Easy1	ImplementationSimulation+2	No attempts yet	2s	512 MB	Judgeable
The Merchant of VeniceSum the cargo values of all ships whose distance is at most s*d, the distance they can cover by the due date.	Easy1	ImplementationMath	No attempts yet	2s	512 MB	Judgeable
Grass Seed Inc.Given the cost per square metre and a list of rectangular lawns, print the total cost of seeding all of them, rounded to seven decimals.	Easy1	MathImplementation	No attempts yet	2s	512 MB	Judgeable
HandballGiven each player's goal counts across M matches, count how many players scored at least once in every match.	Easy1	ArrayImplementation	No attempts yet	2s	512 MB	Judgeable
Zero or OneGiven three bits picked by three players, print the player whose bit differs from the other two, or * if there is no such player.	Easy1	ImplementationBrute force	No attempts yet	1s	512 MB	Judgeable
HistogramRead n bar sizes and print one line of exactly k equals signs for each bar size k.	Easy1	ImplementationString	No attempts yet	2s	512 MB	Judgeable
Pepero DayIgnore the input and print the exact Korean string 빼빼로 데이 on one line.	Easy1	Implementation	No attempts yet	2s	512 MB	Judgeable
Equality CheckRead a quiz line formatted as 'a + b = c' and print YES if a + b equals c, otherwise NO.	Easy1	ImplementationMath	No attempts yet	1s	512 MB	Judgeable
Tournament SelectionCount wins among six game results and print the group number 1, 2, or 3, or -1 if there are no wins.	Easy1	ImplementationString	No attempts yet	2s	512 MB	Judgeable
HelicopterPrint the given ASCII art helicopter exactly as shown, with no trailing spaces on any line.	Easy1	ImplementationString	No attempts yet	1s	512 MB	Judgeable
A toast that wins over the roomGiven one of eight fixed Hangul abbreviations joined by periods, print the full Korean toast phrase it stands for.	Easy1	ImplementationString+1	No attempts yet	2s	512 MB	Judgeable
TunaFor each tuna, take the larger of two estimates when they differ by at most X, otherwise take a third estimate, and print the sum.	Easy1	ImplementationMath	No attempts yet	1s	64 MB	Judgeable
Prime Submission NumberA joke problem with no input and no output: the only accepted submission prints nothing.	Easy1	Implementation	No attempts yet	1s	512 MB	Judgeable
Two Chickens (...)Given two account balances and the price of one chicken, print the leftover total if two chickens can be afforded, otherwise the current total.	Easy1	ImplementationMath+1	No attempts yet	2s	512 MB	Judgeable
The Y Bus Goes VroomSimulate the passenger count as a bus travels N stops with given boarding and alighting numbers, then print the driver's fixed name.	Easy1	SimulationImplementation+1	No attempts yet	2s	256 MB	Judgeable
Pick the QuadrantRead the x and y coordinates of a nonzero point and print which of the four quadrants it lies in.	Easy1	ImplementationMath	No attempts yet	1s	512 MB	Judgeable
Shifty SumGiven N and k, print N + 10N + ... + 10^k N.	Easy1	MathImplementation	No attempts yet	1s	512 MB	Judgeable
Polynomial Derivative (Small)Given the nonzero terms of a polynomial, compute the value of its derivative at x = 1.	Easy1	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
FizzBuzzPrint the numbers 1 through N, writing Fizz for multiples of X, Buzz for multiples of Y, and FizzBuzz for multiples of both.	Easy1	ImplementationMath+2	No attempts yet	1s	512 MB	Judgeable
Counting positive integersGiven a list of integers, count how many are strictly greater than zero and print the count.	Easy1	ImplementationArray	No attempts yet	2s	512 MB	Judgeable