HackMoji

Introduction

The purpose behind Hack-Moji is to use a fun a stimulating way of learning computer programming for my children Hamiltonian and Valerian.

I will add fun and useful examples here as I go.

Examples

These examples are taken from the Brainfuck wikipedia article.

Hello World!

This is the classic "Hello World!" example from so many programming languages.

julia runme("++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++.")

Add two input numbers together

```julia addtwo = """ , Input first number ------------------------------------------------ Make the number character into a real number

                                                Move to cell 1

, Input second number ------------------------------------------------ Remove 48 from character < Move to cell 0 [>+<-] Loop where we decrease the number in cell 0 and increase in cell 1 Move to cell 1 ++++++++++++++++++++++++++++++++++++++++++++++++ Convert the number to a character number . Print the result """ runme(addtwo) ```

Add 5 + 2

This example produces 7 by adding 5 + 2.

```julia addme = """ ++ Cell c0 = 2

+++++ Cell c1 = 5 [ Start your loops with your cell pointer on the loop counter (c1 in our case) < + Add 1 to c0 - Subtract 1 from c1 ] 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 48 = 6 * 8 so let's use another loop to help us! ++++ ++++ c1 = 8 and this will be our loop counter again [ < +++ +++ Add 6 to c0 - Subtract 1 from c1 ] < . Print out c0 which has the value 55 which translates to "7"! """ runme(addme) ```

ROT13 encryption

julia mycode = """ -,+[ 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 """ runme(mycode)