diff options
Diffstat (limited to 'examples')
| -rw-r--r-- | examples/hello_world.bf | 43 | ||||
| -rw-r--r-- | examples/rot13.bf | 28 |
2 files changed, 71 insertions, 0 deletions
diff --git a/examples/hello_world.bf b/examples/hello_world.bf new file mode 100644 index 0000000..2a5b338 --- /dev/null +++ b/examples/hello_world.bf @@ -0,0 +1,43 @@ +[ ; 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 diff --git a/examples/rot13.bf b/examples/rot13.bf new file mode 100644 index 0000000..3ce3faf --- /dev/null +++ b/examples/rot13.bf @@ -0,0 +1,28 @@ +-,+[ ; Read first character and start outer character reading loop + -[ ; Skip forward if character is 0 + >>++++[>++++++++<-] ; Set up divisor (32) for division loop + ; (MEMORY LAYOUT: dividend copy remainder divisor quotient zero zero) + <+<-[ ; Set up dividend (x minus 1) and enter division loop + >+>+>-[>>>] ; Increase copy and remainder / reduce divisor / Normal case: skip forward + <[[>+<-]>>+>] ; Special case: move remainder back to divisor and increase quotient + <<<<<- ; Decrement dividend + ] ; End division loop + ]>>>[-]+ ; End skip loop; zero former divisor and reuse space for a flag + >--[-[<->+++[-]]]<[ ; Zero that flag unless quotient was 2 or 3; zero quotient; check flag + ++++++++++++<[ ; If flag then set up divisor (13) for second division loop + ; (MEMORY LAYOUT: zero copy dividend divisor remainder quotient zero zero) + >-[>+>>] ; Reduce divisor; Normal case: increase remainder + >[+[<+>-]>+>>] ; Special case: increase remainder / move it back to divisor / increase quotient + <<<<<- ; Decrease dividend + ] ; End division loop + >>[<+>-] ; Add remainder back to divisor to get a useful 13 + >[ ; Skip forward if quotient was 0 + -[ ; Decrement quotient and skip forward if quotient was 1 + -<<[-]>> ; Zero quotient and divisor if quotient was 2 + ]<<[<<->>-]>> ; Zero divisor and subtract 13 from copy if quotient was 1 + ]<<[<<+>>-] ; Zero divisor and add 13 to copy if quotient was 0 + ] ; End outer skip loop (jump to here if ((character minus 1)/32) was not 2 or 3) + <[-] ; Clear remainder from first division if second division was skipped + <.[-] ; Output ROT13ed character from copy and clear it + <-,+ ; Read next character +] ; End character reading loop |