public/subjects/brainfuck.en.md

## brainfuck

### Instructions

Write a `Brainfuck` interpreter program.
The source code will be given as first parameter.
The code will always be valid, with less than 4096 operations.
`Brainfuck` is a minimalist language. It consists of an array of bytes (in this exercice 2048 bytes) all initialized with zero, and with a pointer to its first byte.

Every operator consists of a single character :

-   '>' increment the pointer
-   '<' decrement the pointer
-   '+' increment the pointed byte
-   '-' decrement the pointed byte
-   '.' print the pointed byte on standard output
-   '[' go to the matching ']' if the pointed byte is 0 (loop start)
-   ']' go to the matching '[' if the pointed byte is not 0 (loop end)

Any other character is a comment.

### Usage

```console
student@ubuntu:~/piscine-go/brainfuck$ go build
student@ubuntu:~/piscine-go/brainfuck$ ./brainfuck "++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>." | cat -e
Hello World!$
student@ubuntu:~/piscine-go/brainfuck$ ./brainfuck "+++++[>++++[>++++H>+++++i<<-]>>>++\n<<<<-]>>--------.>+++++.>." | cat -e
Hi$
student@ubuntu:~/piscine-go/brainfuck$ ./brainfuck "++++++++++[>++++++++++>++++++++++>++++++++++<<<-]>---.>--.>-.>++++++++++." | cat -e
abc$
student@ubuntu:~/piscine-go/brainfuck$ ./brainfuck | cat -e
$
student@ubuntu:~/piscine-go/brainfuck$
```