All Questions
4,642
questions
44
votes
68
answers
9k
views
Generate Pascal's triangle
Pascal's triangle is generated by starting with a 1 on the first row. On subsequent rows, the number is determined by the sum of the two numbers directly above it to the left and right.
To ...
- 7,712
147
votes
78
answers
25k
views
Interpret brainfuck
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 ...
- 6,066
78
votes
261
answers
25k
views
Is this even or odd?
Note: There is not been a vanilla parity test challenge yet (There is a C/C++ one but that disallows the ability to use languages other than C/C++, and other non-vanilla ones are mostly closed too), ...
- 5,353
66
votes
234
answers
18k
views
Add two numbers
Input: Two integers. Preferably decimal integers, but other forms of numbers can be used. These can be given to the code in standard input, as arguments to the program or function, or as a list.
...
- 6,336
22
votes
24
answers
2k
views
Tips for golfing in sed
What general tips do you have for golfing in sed? I'm looking for ideas which can be applied to code-golf problems and which are also at least somewhat specific to sed (e.g. "remove comments" is not ...
- 6,218
96
votes
15
answers
11k
views
Create a programming language that only appears to be unusable
Robbers' challenge thread is here.
Cops' challenge: Design a programming language that appears to be unusable for programming, but admits computation (or at least completion of the task) through some ...
- 31.3k
30
votes
8
answers
3k
views
crossed out 44 is still regular 44 ;(
Introduction
On March 24th, 2015 @isaacg golfed his Pyth answer from 44 to 42 bytes. Since a crossed out 44 (44) looks a lot like a regular 44, @Optimizer made the following comment:
striked out ...
- 123k
24
votes
14
answers
4k
views
Converting integers to English words
The goal of this code golf is to convert integers to English words.
The program prompts for input. If this input isn't an integer, print NaN. If it is an integer,...
- 8,351
20
votes
26
answers
5k
views
The Work Day Countdown
I just had a genius idea for making the work-life easier - a countdown to a specific date which only counts workdays.
The basic task is to create a countdown to a specific date which only includes ...
- 389
90
votes
212
answers
21k
views
Find the Factorial!
Create the shortest program or function that finds the factorial of a non-negative integer.
The factorial, represented with ! is defined as such
$$n!:=\begin{...
- 6,442
67
votes
140
answers
11k
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 ...
- 3,318
62
votes
48
answers
7k
views
Are the brackets fully matched?
You must write a program or function that takes a string of brackets and outputs whether or not that string is fully matched. Your program should print a truthy or falsy value, and IO can be in any ...
- 58.9k
43
votes
57
answers
8k
views
Catalan Numbers
The Catalan numbers (OEIS) are a sequence of natural numbers often appearing in combinatorics.
The nth Catalan number is the number of Dyck words (balanced strings of parenthesis or brackets such as <...
- 11.2k
33
votes
33
answers
3k
views
Say What You See
The "Look and say" or "Say what you see" sequence is a series of numbers where each describes the last.
...
- 461
28
votes
11
answers
3k
views
Tips for golfing in Lua
What general tips do you have for golfing in Lua? I'm looking for ideas that can be applied to code golf problems in general that are at least somewhat specific to Lua (e.g. "remove comments" is not ...
- 431
22
votes
10
answers
1k
views
Tips for golfing in Prolog
What general tips do you have for golfing in Prolog? I am looking for ideas that can be applied to code golf problems in general that are at least somewhat specific to Prolog (e.g. one letter ...
- 38.4k
22
votes
15
answers
2k
views
Tips for Code Golfing in Desmos
Desmos is mainly used as an online graphing calculator, but its graphical and mathematical functionalities can also be applied in certain coding challenges.
I know not that many people use Desmos on ...
- 12.7k
16
votes
13
answers
2k
views
Tips for golfing in MATLAB
What general tips do you have for golfing in MATLAB? I'm looking for ideas that can be applied to code golf problems in general that are at least somewhat specific to MATLAB (e.g. "remove comments" is ...
- 937
144
votes
566
answers
46k
views
Shortest infinite loop producing no output
Your task is to create the shortest infinite loop!
The point of this challenge is to create an infinite loop producing no output, unlike its possible duplicate. The reason to this is because the code ...
- 13.1k
95
votes
131
answers
20k
views
Print this diamond
This question has been spreading like a virus in my office. There are quite a variety of approaches:
Print the following:
...
- 1,059
86
votes
221
answers
16k
views
Count up forever
Write a program that counts up forever, starting from one.
Rules:
Your program must log to STDOUT or an acceptable alternative, if ...
- 2,499
46
votes
78
answers
10k
views
Is it a leap year?
This challenge is quite simple. You will take an input which will be a year from 1801 to 2400, and output if it is a leap year or not.
Your input will have no newlines or trailing spaces:
...
user40734
301
votes
451
answers
125k
views
Add a language to a polyglot
This is an answer-chaining challenge in which each answer builds on the previous answer. I recommend sorting the thread by "oldest" in order to be sure about the order in which the posts are ...
user62131
239
votes
115
answers
43k
views
Print every character your program doesn't have
Your task is to build a program (using only printable ASCII characters and/or tabs and newlines) that prints out exactly the characters in the printable ASCII space (...
- 34.7k
94
votes
173
answers
16k
views
Print a Tabula Recta!
The Tabula Recta (sometimes called a 'Vigenere Table'), was created by Johannes Trithemius, and has been used in several ciphers, including all variants of Bellaso's Vigenere cipher and the Trithemius ...
user53406
87
votes
135
answers
13k
views
Collatz Conjecture (OEIS A006577)
This is the Collatz Conjecture (OEIS A006577):
Start with an integer n > 1.
Repeat the following steps:
If n is even, divide it by 2.
If n is odd, multiply it by 3 and add 1.
It is proven that ...
- 71.4k
74
votes
139
answers
11k
views
Make a ;# interpreter
I recently created a new language called ;# (pronounced "Semicolon Hash") which only has two commands:
; add one to ...
- 49.4k
47
votes
85
answers
8k
views
Greatest Common Divisor
Your task is to compute the greatest common divisor (GCD) of two given integers in as few bytes of code as possible.
You may write a program or function, taking input and returning output via any of ...
- 717
36
votes
13
answers
3k
views
Tips for golfing in vim
I've recently realized how vim works great for golfing, especially for kolmogorov-complexity. Also, according to meta vim is a perfectly acceptable 'programming language' at least, for the scope of ...
- 58.9k
35
votes
35
answers
7k
views
Random Golf of the Day #1: Shuffle an Array
About the Series
I will be running a little series of code-golf challenges revolving around the theme of randomness. This will basically be a 9-Hole Golf Course, but spread out over several questions....
- 196k
23
votes
18
answers
2k
views
Tips for golfing in Japt
Now that I'm thoroughly addicted to Code Golf, it's probably about time that I try to pick up a few golfing languages.
Given that I play almost exclusively in JavaScript, Japt seems like the logical ...
- 41.6k
15
votes
15
answers
2k
views
Golf the Subset-Sum Problem
Task
Given a list of space-delimited integers as input, output all unique non-empty subsets of these numbers that each subset sums to 0.
Test Case
Input: ...
- 2,172
461
votes
50
answers
173k
views
Images with all colors
Similar to the images on allrgb.com, make images where each pixel is a unique color (no color is used twice and no color is missing).
Give a program that generates such an image, along with a ...
- 7,096
117
votes
84
answers
42k
views
Shortest code that raises a SIGSEGV
Write the shortest code that raises a Segmentation Fault (SIGSEGV) in any programming language.
- 1,369
93
votes
23
answers
12k
views
Programming a Pristine World
Let's define a pristine program as a program that does not have any errors itself but will error if you modify it by removing any contiguous substring of \$N\$ characters, where \$1 \le N < \text{...
- 89.3k
69
votes
126
answers
9k
views
Print/Output the L-phabet
Inspired by George Gibson's Print a Tabula Recta.
You are to print/output this exact text:
...
- 49.6k
49
votes
19
answers
3k
views
Tips for golfing in The Shakespeare Programming Language
What general tips do you have for golfing in The Shakespeare Programming Language? I'm looking for ideas which can be applied to code-golf problems and which are also at least somewhat specific to SPL ...
- 8,102
45
votes
23
answers
4k
views
Levenshtein Distance
While there are many edit distance questions, such as this one, there isn't a simple question to write a program that calculates the Levenshtein distance.
Some Exposition
The Levenshtein edit ...
- 12.2k
36
votes
17
answers
12k
views
Find the nth decimal of pi
There are already 30 challenges dedicated to pi but not a single one asks you to find the nth decimal, so...
Challenge
For any integer in the range of ...
- 5,909
36
votes
49
answers
4k
views
Least Common Multiple
The least common multiple of a set of positive integers A is the smallest postive integer B such that, for each ...
user45941
28
votes
12
answers
2k
views
Tips for golfing in TI-BASIC
What general tips do you have for golfing in TI-BASIC for the TI-83/84+ series calculators? I'm looking for ideas which can be applied to code-golf problems and which are also at least somewhat ...
- 21.4k
28
votes
16
answers
3k
views
Tips for golfing in Scala
What general tips do you have for golfing in Scala? I'm looking for ideas that can be applied to code golf problems in general that are at least somewhat specific to Scala (e.g. "remove comments" is ...
- 4,591
24
votes
26
answers
3k
views
Find the prime factors
In this task, you have to write a program, that computes the prime factors of a number. The input is a natural number 1 < n < 2^32. The output is a list of the prime factors of the number in the ...
- 10.1k
21
votes
16
answers
7k
views
Tips for Golfing in T-SQL
What general tips do you have for golfing in T-SQL? I'm looking for ideas that can be applied to code golf problems in general that are at least somewhat specific to T-SQL. Please post one tip per ...
- 1,631
18
votes
11
answers
1k
views
Tips for golfing in Octave
What general tips do you have for golfing in Octave? I'm looking for ideas that can be applied to code golf problems in general that are at least somewhat specific to Octave (e.g. "remove comments" is ...
- 937
42
votes
17
answers
6k
views
Tips for restricted source in Python
Just like code-golf, restricted-source pushes one to exploit quirks and hidden features of the Python language. We already have a place to collect all these tips for code-golf, those for restricted-...
- 96.5k
198
votes
212
answers
45k
views
The Programming Language Quiz
Congratulations to Dennis who won both the cops' and the robbers' challenge! Calvin's Hobbies has already delivered on his promise and wrote this challenge for Dennis for winning the robbers' ...
- 196k
197
votes
120
answers
27k
views
I'm not the language you're looking for!
Isn't it annoying when you find a piece of code and you don't know what language it was written in? This challenge attempts to somewhat solve this.
Challenge
You will have to write a program that ...
- 28.5k
145
votes
333
answers
31k
views
Shortest code to produce infinite output
Write the shortest code you can that produces an infinite output.
That's all. You code will only be disqualified if it stops producing output at some point. As always in code golf, the shortest code ...
- 2,416
111
votes
286
answers
18k
views
Output with the same length as the code
In this challenge, you should write a program or function which takes no input and prints or returns a string with the same number of bytes as the program itself. There are a few rules:
You may only ...
- 196k