All Questions

15
votes
2answers
671 views

Quine that takes as input the name of a language and outputs the same thing implemented in the input language

From Quine central: Write a quine that takes as input the name of a language and outputs the same thing implemented in the input language. The source article has something you can work from, but as ...
7
votes
26answers
2k views

Shortest Floor Function

Your task is to implement a floor function in as few bytes as possible. A floor function is a function that takes a real number and returns the largest integer less than or equal to the input. Your ...
41
votes
11answers
12k views

Write an interpreter for the untyped lambda calculus

The challenge is to write an interpreter for the untyped lambda calculus in as few characters as possible. We define the untyped lambda calculus as follows: Syntax There are the following three ...
27
votes
15answers
10k views

Twinkle Twinkle Little Star

Write a program to play the popular English nursery rhyme. (This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. Attribution: Helix84 at the English language ...
6
votes
1answer
2k views

Nokia mystery puzzle [closed]

A friend sent me this puzzle. I'm pretty sure solving it will require some programming. Can anyone crack it? The original is here in case of encoding issues in the past below. ...
11
votes
2answers
4k views

Decryption by pattern analysis

You are given an encrypted string, encrypted using a very simple substitution cipher. Problem You do not know what the cipher is but you do know the ciphertext is English and that the most frequent ...
25
votes
17answers
8k views

Print 1 to 1000 in C++ without semi-colons

Following this popular question, present your solution which prints the numbers 1 to 1000 (all of them, not the string "1 to 1000" verbatim or something funny) in C++ without using any semi-colons. ...
19
votes
5answers
4k views

Print a random maze

Write a program that generates and prints a random maze using the algorithm of your choice. The maze should be different for multiple runs of the program. Height and width are given as command line ...
55
votes
90answers
7k views

Reverse stdin and place on stdout

Requirements: Take an input on stdin including new lines / carriage returns of unlimited length (only bounded by system memory; that is, there is no inherent limit in the program.) Output the reverse ...
39
votes
40answers
6k views

Reverse Polish notation

You must evaluate a string written in Reverse Polish notation and output the result. The program must accept an input and return the output. For programming languages that do not have functions to ...
16
votes
8answers
609 views

Compute modular inverse

Given two positive numbers x and n with x<2^n, write the shortest possible function to ...
16
votes
2answers
913 views

Slot Machine Hacker

Problem: Slot Machine Hacker from Facebook Hacker Cup 2011 Round 1B Goal: Shortest code in your favourite language using stdin/stdout. You cannot assume ...
14
votes
4answers
758 views

Freely available books for code golfing? [closed]

Can you recommend any freely available books about code golfing in general and especially in Java and C++?
44
votes
39answers
4k views

Tips for golfing in PowerShell

What general tips do you have for golfing in Windows PowerShell? I'm looking for ideas that can be applied to code golf problems in general that are at least somewhat specific to PowerShell (e.g. "...
32
votes
13answers
11k views

Drawing a cube in ASCII art

Task description: Draw a cube in ASCII art in roughly a cabinet projection. Monospaced fonts often have characters that are about twice as high as they are wide. ...
6
votes
33answers
3k views

Print largest integer you can with the fewest characters [closed]

Find a way to output a large integer with few characters. Solutions will be scored based on the magnitude of the number and shortness of code. EDIT: Let's impose a time limit of a minute on sensible ...
21
votes
25answers
2k views

Finding “sub-palindromes”.

The shortest code that finds all unique "sub-palindromes" of a string, that is: any substring with length > 1 that is a palindrome. eg.1 ...
57
votes
46answers
12k views

Tips for code-golfing in C#

What general tips do you have for golfing in C#? I'm looking for ideas that can be applied to code golf problems in general that are at least somewhat specific to C# (e.g. "remove comments" is not an ...
34
votes
43answers
3k views

196 algorithm code golf

Write a short program for 196-algorithm. The algorithm starts from an integer, then adds its reverse to it until a palindrome is reached. e.g. ...
12
votes
1answer
882 views

Shortest path in a graph

Write a program to take a graph (from either standard input or a file, your choice) and find a shortest path in the graph. Graphs are specified using the following format: ...
6
votes
3answers
355 views

Compress programs

Write a program/script that decompresses and passes any compressed data appended at the end of the binary/file as standard input to a program specified as arguments. ...
11
votes
1answer
627 views

Write a compressing util for gzip files

The task of this challenge is as following: Write a program that reads a file of reasonable size (let's say <16 MB) from stdin or anywhere else (however you like, but must not be hardcoded), and ...
42
votes
21answers
11k views

Tips for golfing in C++

What general tips do you have for golfing in C++? I'm looking for ideas that can be applied to code golf problems in general that are at least somewhat specific to C++ (e.g. "remove comments" is not ...
28
votes
22answers
9k views

Morse code translator

Write the shortest program to transform the standard input into Morse code. Characters not in the table should be printed as they are.
-1
votes
1answer
4k views

Poisson random number generator [closed]

What is the shortest function (implemented in C) that will return a random draw from a Poisson distribution (given the mean or λ parameter)? ...
14
votes
2answers
2k views

Test if a given number is a Vampire Number

EDIT: In the interest of increasing the complexity, i've added more to the challenge. In mathematics, a vampire number (or true vampire number) is a composite natural number v, with an even ...
7
votes
5answers
781 views

Tree traversal.

Write the shortest code that traverses a tree, breadth-first. Input any way you like Output a list of "names" of the nodes in correct order.
26
votes
42answers
3k views

Sum of primes between given range

Write the shortest code for finding the sum of primes between a and b (inclusive). Input a ...
4
votes
3answers
243 views

Sharing Inherited Land [closed]

You and your brother have inherited a rectanglar block of land. This block of land's corners are read in from stdio as TLX,TLY,TRX,TRY,BLX,BLY,BRX,BRY (all decimal ...
50
votes
41answers
15k views

Obfuscated FizzBuzz Golf [closed]

Create the shortest possible obfuscated FizzBuzz implementation. To be considered obfuscated, it should satisfy at least one of the following: Does not contain any of the words "Fizz", "Buzz", or "...
108
votes
218answers
23k views

Fibonacci function or sequence

The Fibonacci sequence is a sequence of numbers, where every number in the sequence is the sum of the two numbers preceding it. The first two numbers in the sequence are both 1. Here are the first ...
110
votes
50answers
15k views

Interpret brainf***

Write the shortest program in your favourite language to interpret a brainfuck program. The program is read from a file. Input and output are standard input and standard output. Cell size: 8bit ...
24
votes
38answers
3k views

Reimplementing square root [duplicate]

Define a function, s, which takes a number and returns the square root. No use of library functions, such as Java's Math.sqrt() or PHP's built in sqrt(), allowed.
184
votes
301answers
38k views

Golf you a quine for great good!

Using your language of choice, golf a quine. A quine is a non-empty computer program which takes no input and produces a copy of its own source code as its only output. No cheating -- that means ...
230
votes
136answers
68k views

Tips for golfing in Python

What general tips do you have for golfing in Python? I'm looking for ideas which can be applied to code-golf problems and which are also at least somewhat specific to Python (e.g. "remove comments" is ...
11
votes
5answers
651 views

Fast Topswops calculation

From AZSPCS: Suppose you have a deck containing n cards. Each card contains a number from 1 to n, and each number appears on exactly one card. You look at the number on the top card -- let's says it'...
9
votes
4answers
2k views

Fast line drawing algorithm

The task is to find a way to draw a horizontal line in an array of 16-bit integers. We're assuming a 256x192 pixel array with 16 pixels per word. A line is a contiguous run of set (1) bits. Lines ...
35
votes
21answers
6k views

Angle between the hands on a clock

Given the time in 24 hour format (2359 = 11:59pm) return the angle between the minute and hour hands on a standard clock (on the ...
4
votes
7answers
796 views

Find an unknown very large number [closed]

Let's suppose there is a finite unknown number n (n can be very large, does not necessarily fit 64-bits; think of ...
9
votes
4answers
1k views

fizz buzz in TMP

The Fizz Buzz problem is a very basic problem to solve that is used by some to weed out interviewees that don't know how to program. The problem is: ...
43
votes
39answers
4k views

The Luhn algorithm for verifying credit card numbers, etc

Challenge Write the shortest program or function to calculate the Luhn Algorithm for verifying (credit card) numbers. Luhn algorithm explained From RosettaCode, this algorithm for the purposes of ...
29
votes
31answers
13k views

Rand5() to Rand7() [closed]

You are provided with a function Rand5(). This function returns perfectly random (equal distribution) integers between 1 and 5. Provide the function Rand7(), which uses Rand5() to produce perfectly ...
9
votes
4answers
2k views

N-Queens problem [closed]

In chess, a queen can move as far as as the board extends horizontally, vertically, or diagonally. Given a NxN sized chessboard, print out how many possible positions N queens can be placed on the ...
14
votes
7answers
3k views

Hamming numbers

Given a positive integer, print that many hamming numbers, in order. Rules: input will be a positive integer such that n <= 1,000,000 execution time must be < 1 minute This is Code Golf, ...
33
votes
44answers
4k views

ROT-13 transform standard input

The challenge: To read an input of arbitrary length and produce the ROT13 of the input. All characters besides A-Z should be copied to the output verbatim, and case should be preserved if possible. ...
65
votes
117answers
19k views

99 Bottles Of Beer [closed]

Recreate '99 bottles of beers on the wall'. The desired output is this: ...
22
votes
5answers
3k views

Just Another Perl Hacker [closed]

Classic code golf challenge. Write the most obscure Perl program to print "Just another Perl hacker". Here's the Wikipedia article on it. Bonus points if it fits in 3 lines / 70 characters each.
87
votes
95answers
13k views

Code Golf Christmas Edition: How to print out a Christmas tree of height N

Given a number N, how can I print out a Christmas tree of height N using the least number of code characters? ...

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