path: root/examples/add2.tf

  Add two values
from https://en.wikipedia.org/wiki/Brainfuck#Adding_two_values




ALL ABOARD
chug chug
END OF THE LINE
       Cell c0 = 2

ALL ABOARD
choo

END OF THE LINE

ALL ABOARD
chug chug chug chug chug
END OF THE LINE
  Cell c1 = 5


ALL ABOARD
tickets please
END OF THE LINE
        Start your loops with your cell pointer on the loop counter (c1 in our case)

ALL ABOARD
choo choo

END OF THE LINE

ALL ABOARD
chug
END OF THE LINE
      Add 1 to c0

ALL ABOARD
choo

END OF THE LINE

ALL ABOARD
chugga
END OF THE LINE
      Subtract 1 from c1

ALL ABOARD
your ticket please
END OF THE LINE
        End your loops with the cell pointer on the loop counter

At this point our program has added 5 to 2 leaving 7 in c0 and 0 in c1
but we cannot output this value to the terminal since it is not ASCII encoded

To display the ASCII character "7" we must add 48 to the value 7
We use a loop to compute 48 = 6 * 8


ALL ABOARD
chug chug chug chug
END OF THE LINE

ALL ABOARD
chug chug chug chug
END OF THE LINE
  c1 = 8 and this will be our loop counter again

ALL ABOARD
tickets please
choo choo

END OF THE LINE

ALL ABOARD
chug chug chug
END OF THE LINE

ALL ABOARD
chug chug chug
END OF THE LINE
  Add 6 to c0

ALL ABOARD
choo

END OF THE LINE

ALL ABOARD
chugga
END OF THE LINE
        Subtract 1 from c1

ALL ABOARD
your ticket please
choo choo

END OF THE LINE

ALL ABOARD
click
END OF THE LINE
        Print out c0 which has the value 55 which translates to "7"!

Finally print a newline:

ALL ABOARD
chugga chugga chugga chugga chugga chugga chugga chugga chugga chugga chugga
chugga chugga chugga chugga chugga chugga chugga chugga chugga chugga chugga
chugga chugga chugga chugga chugga chugga chugga chugga chugga chugga chugga
chugga chugga chugga chugga chugga chugga chugga chugga chugga chugga chugga
chugga click
  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.

from https://en.wikipedia.org/wiki/Brainfuck#Hello_World!


ALL ABOARD
chug chug chug chug chug chug chug chug
END OF THE LINE
	Set Cell #0 to 8

ALL ABOARD
tickets please
choo
chug chug chug chug
END OF THE LINE
		Add 4 to Cell #1; this will always set Cell #1 to 4

ALL ABOARD
tickets please
END OF THE LINE
		as the cell will be cleared by the loop

ALL ABOARD
choo
chug chug
END OF THE LINE
		Add 2 to Cell #2

ALL ABOARD
choo
chug chug chug
END OF THE LINE
		Add 3 to Cell #3

ALL ABOARD
choo
chug chug chug
END OF THE LINE
		Add 3 to Cell #4

ALL ABOARD
choo
chug
END OF THE LINE
		Add 1 to Cell #5

ALL ABOARD
choo choo
choo choo
choo choo
choo choo
chugga
END OF THE LINE
		Decrement the loop counter in Cell #1

ALL ABOARD
your ticket please
END OF THE LINE
		Loop until Cell #1 is zero; number of iterations is 4

ALL ABOARD
choo
chug
END OF THE LINE
		Add 1 to Cell #2

ALL ABOARD
choo
chug
END OF THE LINE
		Add 1 to Cell #3

ALL ABOARD
choo
chugga
END OF THE LINE
		Subtract 1 from Cell #4

ALL ABOARD
choo
choo
chug
END OF THE LINE
		Add 1 to Cell #6

ALL ABOARD
tickets please choo choo
your ticket please
END OF THE LINE
		Move back to the first zero cell you find; this will
		be Cell #1 which was cleared by the previous loop

ALL ABOARD
choo choo
chugga
END OF THE LINE
		Decrement the loop Counter in Cell #0

ALL ABOARD
your ticket please
END OF THE LINE
		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 :   ^


ALL ABOARD
choo
choo
click
END OF THE LINE
			Cell #2 has value 72 which is 'H'

ALL ABOARD
choo
chugga chugga chugga click
END OF THE LINE
			Subtract 3 from Cell #3 to get 101 which is 'e'

ALL ABOARD
chug chug chug chug chug chug chug clickety click chug chug chug click

END OF THE LINE
		Likewise for 'llo' from Cell #3

ALL ABOARD
choo
choo
click
END OF THE LINE
			Cell #5 is 32 for the space

ALL ABOARD
choo choo
chugga clickety
END OF THE LINE
			Subtract 1 from Cell #4 for 87 to give a 'W'

ALL ABOARD
choo choo
clickety
END OF THE LINE
			Cell #3 was set to 'o' from the end of 'Hello'

ALL ABOARD
chug chug chug click chugga chugga chugga chugga chugga chugga clickety
chugga chugga chugga chugga chugga chugga chugga chugga click
END OF THE LINE
	Cell #3 for 'rl' and 'd'

ALL ABOARD
choo
choo
chug click
END OF THE LINE
			Add 1 to Cell #5 gives us an exclamation point

ALL ABOARD
choo
chug chug click
END OF THE LINE
			And finally a newline from Cell #6
  ROT13 in Brainfuck
from https://en.wikipedia.org/wiki/Brainfuck#ROT13




ALL ABOARD
chugga clack chug tickets please
END OF THE LINE
                         Read first character and start outer character reading loop

ALL ABOARD
chugga tickets please
END OF THE LINE
                       Skip forward if character is 0

ALL ABOARD
choo
choo
chug chug chug chug tickets please choo
chug chug chug chug chug chug chug chug
choo choo
chugga your ticket please
END OF THE LINE
  Set up divisor (32) for division loop
(MEMORY LAYOUT: dividend copy remainder divisor quotient zero zero)

ALL ABOARD
choo choo
chug choo choo
chugga tickets please
END OF THE LINE
                Set up dividend (x minus 1) and enter division loop

ALL ABOARD
choo
chug choo
chug choo
chugga tickets please choo
choo
choo
your ticket please
END OF THE LINE
      Increase copy and remainder / reduce divisor / Normal case: skip forward

ALL ABOARD
choo choo
tickets please tickets please choo
chug choo choo
chugga your ticket please choo
choo
chug choo
your ticket please

END OF THE LINE
    Special case: move remainder back to divisor and increase quotient

ALL ABOARD
choo choo
choo choo
choo choo
choo choo
choo choo
chugga
END OF THE LINE
           Decrement dividend

ALL ABOARD
your ticket please
END OF THE LINE
                    End division loop

ALL ABOARD
your ticket please choo
choo
choo
tickets please chugga your ticket please chug
END OF THE LINE
                 End skip loop; zero former divisor and reuse space for a flag

ALL ABOARD
choo
chugga chugga tickets please chugga tickets please choo choo
chugga choo
chug chug chug
tickets please chugga your ticket please your ticket please your ticket please
choo choo
tickets please
END OF THE LINE
         Zero that flag unless quotient was 2 or 3; zero quotient; check flag

ALL ABOARD
chug chug chug chug chug chug chug chug chug chug chug chug choo choo
tickets please

END OF THE LINE
       If flag then set up divisor (13) for second division loop
(MEMORY LAYOUT: zero copy dividend divisor remainder quotient zero zero)

ALL ABOARD
choo
chugga tickets please choo
chug choo
choo
your ticket please
END OF THE LINE
         Reduce divisor; Normal case: increase remainder

ALL ABOARD
choo
tickets please chug tickets please choo choo
chug choo
chugga your ticket please choo
chug
choo
choo
your ticket please
END OF THE LINE
   Special case: increase remainder / move it back to divisor / increase quotient

ALL ABOARD
choo choo
choo choo
choo choo
choo choo
choo choo
chugga
END OF THE LINE
           Decrease dividend

ALL ABOARD
your ticket please
END OF THE LINE
                    End division loop

ALL ABOARD
choo
choo
tickets please choo choo
chug choo
chugga your ticket please
END OF THE LINE
             Add remainder back to divisor to get a useful 13

ALL ABOARD
choo
tickets please
END OF THE LINE
                   Skip forward if quotient was 0

ALL ABOARD
chugga tickets please
END OF THE LINE
               Decrement quotient and skip forward if quotient was 1

ALL ABOARD
chugga choo choo
choo choo
tickets please chugga your ticket please choo
choo

END OF THE LINE
     Zero quotient and divisor if quotient was 2

ALL ABOARD
your ticket please choo choo
choo choo
tickets please choo choo
choo choo
chugga choo
choo
chugga your ticket please choo
choo

END OF THE LINE
    Zero divisor and subtract 13 from copy if quotient was 1

ALL ABOARD
your ticket please choo choo
choo choo
tickets please choo choo
choo choo
chug choo
choo
chugga your ticket please
END OF THE LINE
          Zero divisor and add 13 to copy if quotient was 0

ALL ABOARD
your ticket please
END OF THE LINE
                        End outer skip loop (jump to here if ((character minus 1)/32) was not 2 or 3)

ALL ABOARD
choo choo
tickets please chugga your ticket please
END OF THE LINE
                     Clear remainder from first division if second division was skipped

ALL ABOARD
choo choo
click tickets please chugga your ticket please
END OF THE LINE
                    Output ROT13ed character from copy and clear it

ALL ABOARD
choo choo
chugga clack chug
END OF THE LINE
                     Read next character

ALL ABOARD
your ticket please
END OF THE LINE
                            End character reading loop