From 5aa692f5f3bbfa7b79224748dcfd8ca5fba7a8bc Mon Sep 17 00:00:00 2001 From: Adam Date: Fri, 12 Feb 2016 11:42:25 -0800 Subject: brainfuck->bf --- brainfuck.html.markdown | 81 ------------------------------------------------- 1 file changed, 81 deletions(-) delete mode 100644 brainfuck.html.markdown (limited to 'brainfuck.html.markdown') diff --git a/brainfuck.html.markdown b/brainfuck.html.markdown deleted file mode 100644 index a76169c8..00000000 --- a/brainfuck.html.markdown +++ /dev/null @@ -1,81 +0,0 @@ ---- -language: brainfuck -contributors: - - ["Prajit Ramachandran", "http://prajitr.github.io/"] - - ["Mathias Bynens", "http://mathiasbynens.be/"] ---- - -Brainfuck (not capitalized except at the start of a sentence) is an extremely -minimal Turing-complete programming language with just 8 commands. - -You can try brainfuck on your browser with [brainfuck-visualizer](http://fatiherikli.github.io/brainfuck-visualizer/). - -``` -Any character not "><+-.,[]" (excluding quotation marks) is ignored. - -Brainfuck is represented by an array with 30,000 cells initialized to zero -and a data pointer pointing at the current cell. - -There are eight commands: -+ : Increments the value at the current cell by one. -- : Decrements the value at the current cell by one. -> : Moves the data pointer to the next cell (cell on the right). -< : Moves the data pointer to the previous cell (cell on the left). -. : Prints the ASCII value at the current cell (i.e. 65 = 'A'). -, : Reads a single input character into the current cell. -[ : If the value at the current cell is zero, skips to the corresponding ] . - Otherwise, move to the next instruction. -] : If the value at the current cell is zero, move to the next instruction. - Otherwise, move backwards in the instructions to the corresponding [ . - -[ and ] form a while loop. Obviously, they must be balanced. - -Let's look at some basic brainfuck programs. - -++++++ [ > ++++++++++ < - ] > +++++ . - -This program prints out the letter 'A'. First, it increments cell #1 to 6. -Cell #1 will be used for looping. Then, it enters the loop ([) and moves -to cell #2. It increments cell #2 10 times, moves back to cell #1, and -decrements cell #1. This loop happens 6 times (it takes 6 decrements for -cell #1 to reach 0, at which point it skips to the corresponding ] and -continues on). - -At this point, we're on cell #1, which has a value of 0, while cell #2 has a -value of 60. We move on cell #2, increment 5 times, for a value of 65, and then -print cell #2's value. 65 is 'A' in ASCII, so 'A' is printed to the terminal. - - -, [ > + < - ] > . - -This program reads a character from the user input and copies the character into -cell #1. Then we start a loop. Move to cell #2, increment the value at cell #2, -move back to cell #1, and decrement the value at cell #1. This continues on -until cell #1 is 0, and cell #2 holds cell #1's old value. Because we're on -cell #1 at the end of the loop, move to cell #2, and then print out the value -in ASCII. - -Also keep in mind that the spaces are purely for readability purposes. You -could just as easily write it as: - -,[>+<-]>. - -Try and figure out what this program does: - -,>,< [ > [ >+ >+ << -] >> [- << + >>] <<< -] >> - -This program takes two numbers for input, and multiplies them. - -The gist is it first reads in two inputs. Then it starts the outer loop, -conditioned on cell #1. Then it moves to cell #2, and starts the inner -loop conditioned on cell #2, incrementing cell #3. However, there comes a -problem: At the end of the inner loop, cell #2 is zero. In that case, -inner loop won't work anymore since next time. To solve this problem, -we also increment cell #4, and then recopy cell #4 into cell #2. -Then cell #3 is the result. -``` - -And that's brainfuck. Not that hard, eh? For fun, you can write your own -brainfuck programs, or you can write a brainfuck interpreter in another -language. The interpreter is fairly simple to implement, but if you're a -masochist, try writing a brainfuck interpreter… in brainfuck. -- cgit v1.2.3