193k views

### "Hello, World!"

So... uh... this is a bit embarrassing. But we don't have a plain "Hello, World!" challenge yet (despite having 35 variants tagged with hello-world, and counting). While this is not the most ...
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65k views

### Is this number a prime?

Believe it or not, we do not yet have a code golf challenge for a simple primality test. While it may not be the most interesting challenge, particularly for "usual" languages, it can be nontrivial in ...
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22k views

### Simple cat program

One of the most common standard tasks (especially when showcasing esoteric programming languages) is to implement a "cat program": read all of STDIN and print it to STDOUT. While this is named after ...
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20k views

### "DDoouubbllee ssppeeaakk!!"

Super simple challenge today, or is it? I feel like we've heard a fair bit about double speak recently, well let's define it in a codable way... Double speak is when each and every character in a ...
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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), ...
• 5,347
13k views

### Draw an asterisk triangle

Inspired by a task for Programming 101, here's a challenge that hopefully isn't too easy (or a duplicate). Input: A positive integer n >= 1. Output: ...
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11k views

### Make a ;# interpreter

I recently created a new language called ;# (pronounced "Semicolon Hash") which only has two commands: ; add one to ...
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11k views

### Is it double speak?

In an earlier challenge I asked code golfers to produce strings which copy each character in a string. For example: TThhiiss iiss ddoouubbllee ssppeeaakk!! This ...
• 11.8k
9k views

### Convert YYYYMM to MMMYY

Basing on this SO question. Challenge is rather simple: given a date period in the format YYYYMM output it in the format MMMYY. ...
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7k views

### Stack Exchange Vote Simulator

Write a program or function that takes in a string only containing the characters ^ and v (you can assume there will be no other ...
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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 ...
5k views

### Generate Recamán's sequence

Recamán's sequence (A005132) is a mathematical sequence, defined as such: A(0) = 0 A(n) = A(n-1) - n if A(n-1) - n > 0 and is new, else A(n) = A(n-1) + n A ...
• 2,073
3k views

### Find the first word starting with each letter

Given a string, find the first word starting with each letter (case insensitive). Sample Using Ferulas flourish in gorgeous gardens. as input: ...
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