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[ ; 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
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