使用 rust 对 Brainfuck 的解释，并运行。
Brainfuck是Urban Müller 于 1993 年创建的一种深奥的编程语言。
该语言以其极简主义着称，仅包含八个简单的命令、一个数据指针和一个指令指针。虽然它是完全图灵完备的，但它并不是为了实际使用，而是为了挑战和娱乐程序员。Brainfuck 需要将命令分解为微观步骤。
该语言的名称参考了俚语术语brainfuck，它指的是非常复杂或不寻常的事物，以至于超出了人们的理解范围，因为它并不是为了设计实际软件而设计的，而是为了挑战计算机编程的界限。
// 打印 hello world
[ This program prints "Hello World!" and a newline to the screen, its
length is 106 active command characters. [It is not the shortest.]
This loop is an "initial comment loop", a simple way of adding a comment
to a BF program such that you don't have to worry about any command
characters. Any ".", ",", "+", "-", "<" and ">" characters are simply
ignored, the "[" and "]" characters just have to be balanced. This
loop and the commands it contains are ignored because the current cell
defaults to a value of 0; the 0 value causes this loop to be skipped.
]
++++++++ Set Cell #0 to 8
[
>++++ Add 4 to Cell #1; this will always set Cell #1 to 4
[ as the cell will be cleared by the loop
>++ Add 2 to Cell #2
>+++ Add 3 to Cell #3
>+++ Add 3 to Cell #4
>+ Add 1 to Cell #5
<<<<- Decrement the loop counter in Cell #1
] Loop until Cell #1 is zero; number of iterations is 4
>+ Add 1 to Cell #2
>+ Add 1 to Cell #3
>- Subtract 1 from Cell #4
>>+ Add 1 to Cell #6
[<] Move back to the first zero cell you find; this will
be Cell #1 which was cleared by the previous loop
<- Decrement the loop Counter in Cell #0
] Loop until Cell #0 is zero; number of iterations is 8
The result of this is:
Cell no : 0 1 2 3 4 5 6
Contents: 0 0 72 104 88 32 8
Pointer : ^
>>. Cell #2 has value 72 which is 'H'
>---. Subtract 3 from Cell #3 to get 101 which is 'e'
+++++++..+++. Likewise for 'llo' from Cell #3
>>. Cell #5 is 32 for the space
<-. Subtract 1 from Cell #4 for 87 to give a 'W'
<. Cell #3 was set to 'o' from the end of 'Hello'
+++.------.--------. Cell #3 for 'rl' and 'd'
>>+. Add 1 to Cell #5 gives us an exclamation point
>++. And finally a newline from Cell #6以上代码也可写为
++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++.
目前打印较慢，需要做一些优化