This document introduces esoteric programming languages like Brainfuck and Piet. It explains that these Turing complete languages can simulate any computation and are equivalent to other programming languages in their capabilities. It then demonstrates how Brainfuck performs basic operations like addition and division using only eight simple instructions to manipulate data in a one-dimensional array. Piet is described as a language where programs are images composed of different colors, with transitions representing instructions. The document encourages learning these languages for fun, to stimulate creativity, and grasp theoretical computer science concepts like Turing machines.

1. Learn You a Brainfuck for Great Good!
Antoine Leblanc
@nicuveo
January, 2014
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2. Esoteric languages
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Have fun?
Mess with your brain?
Explore new paradigms?
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3. Esoteric languages
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Have fun!
Mess with your brain!
Explore new paradigms!
...all of the above!
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5. Whitespace
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6. Today’s menu
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Turing-completeness
Brainfuck
Piet
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7. Today’s menu
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Turing-completeness
Brainfuck
Piet
⇒ Great good!
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8. Turing machine
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Infinite ribbon of (finite state) cells
Left / right movement
Choice and action on current cell
Can solve all possible algorithmic computations
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9. Turing complete languages
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Simulate any Turing machine
⇒ all possible algorithmic computations
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10. Turing complete languages
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Simulate any Turing machine
⇒ all possible algorithmic computations
⇒ all possible programs!
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11. Turing complete languages
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Simulate any Turing machine
⇒ all possible algorithmic computations
⇒ all possible programs!
⇒ ...“equivalent” to all other Turing-complete languages!
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12. Brainfuck
Left / right movement
Increment / decrement
Test “loop”
Byte IO
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<
+
[
,
>
]
.
“Infinite” buffer of byte cells
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13. Brainfuck - Addition
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14. Brainfuck - Addition
> [ - < + > ] <
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15. Brainfuck - Divmod
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16. Brainfuck - Divmod
>>>>>>>[-]<<<<<[-]<<[->>+<<]>>>[-]<<<[-]>>[-<<+>>>+<]>[-<+>][-]<<[->>+<<]>>>[-]<<<[]>>[-<<+>>>+<]>[-<+>][-]<<[->>+<<][-]>[-<+>][-]>[-<+>]>>[-]+<<<<[->>>>[-]<<[-]>[-]<<[>>+<+<]>[-<+>]>[[-]<<->>>[-]+<]<<<]>[[-]>>>[-]+<<<]>>>[>+<<<<[-]<<[->>+<<]>>>[-]<<<[]>>[-<<+>>>+<]>[-<+>]<[-<<<->>>]<[-]<<[->>+<<]>>>[-]<<<[-]>>[-<<+>>>+<]>[-<+>][-]<<[>>+<<]>>>[-]<<<[-]>>[-<<+>>>+<]>[-<+>][-]<<[->>+<<][-]>[-<+>][-]>[-<+>]>>[-]+<<<<[>>>>[-]<<[-]>[-]<<[->>+<+<]>[-<+>]>[[-]<<->>>[-]+<]<<<]>[[-]>>>[-]+<<<]>>>][-]<<<<<<[>>>>>>+<<<<<<]>>>>>>
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17. Piet
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Image as source
20 significant colors (18 + B&W)
Color transition: 17 instructions
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18. Piet!
?
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19. Piet!
Painting
Program
Composition with Red, Yellow and Blue
Piet Mondrian
Prints “Piet”
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20. Piet!!
Prints “Hello, world!”
Prints “Hello, world!”
Prime factor decomposition
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21. Why don’t we have both?
Brainfuck interpreter
http://www.dangermouse.net/esoteric/piet/samples.html
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22. What else?
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Malbolge
(=<`#9]~6ZY32Vx/4Rs+0No-&Jk)"Fh}|Bcy?`=*z]Kw%oG4UUS0/@-ejc(:'8dc
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Unlambda
`r```````````.H.e.l.l.o. .w.o.r.l.di
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LOLCODE
HAI; CAN HAS STDIO?; VISIBLE "HAI WORLD!"; KTHXBYE;
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23. What else?
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Malbolge
(=<`#9]~6ZY32Vx/4Rs+0No-&Jk)"Fh}|Bcy?`=*z]Kw%oG4UUS0/@-ejc(:'8dc
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Unlambda
`r```````````.H.e.l.l.o. .w.o.r.l.di
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LOLCODE
HAI; CAN HAS STDIO?; VISIBLE "HAI WORLD!"; KTHXBYE;
http://esolangs.org/
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24. Aforementioned great good
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Impress / frighten your friends!
Draw nice pictures!
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25. Aforementioned great good
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Impress / frighten your friends!
Draw nice pictures!
Grasp Turing machines!
Stimulate your creativity!
Feed your curiosity!
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26. Aforementioned great good
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Impress / frighten your friends!
Draw nice pictures!
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Grasp Turing machines!
Stimulate your creativity!
Feed your curiosity!
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Give a talk!
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27. The End
Have fun!
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