Robert Griesemer | 9bc7b08 | 2008-05-08 17:12:15 -0700 | [diff] [blame] | 1 | // $G $F.go && $L $F.$A && ./$A.out |
| 2 | |
| 3 | // Copyright 2009 The Go Authors. All rights reserved. |
| 4 | // Use of this source code is governed by a BSD-style |
| 5 | // license that can be found in the LICENSE file. |
| 6 | |
| 7 | package main |
| 8 | |
| 9 | // brainfuck |
| 10 | |
| 11 | func main() { |
Rob Pike | c0c3025 | 2008-05-15 15:20:59 -0700 | [diff] [blame] | 12 | var a [30000]byte; |
Rob Pike | 126150d | 2008-06-06 13:28:03 -0700 | [diff] [blame] | 13 | prog := "++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>.!"; |
Rob Pike | c0c3025 | 2008-05-15 15:20:59 -0700 | [diff] [blame] | 14 | p := 0; |
| 15 | pc := 0; |
| 16 | for { |
| 17 | switch prog[pc] { |
| 18 | case '>': |
| 19 | p++; |
| 20 | case '<': |
| 21 | p--; |
| 22 | case '+': |
| 23 | a[p]++; |
| 24 | case '-': |
| 25 | a[p]--; |
| 26 | case '.': |
Rob Pike | bc2f5f1 | 2008-08-11 22:07:49 -0700 | [diff] [blame] | 27 | print(string(a[p])); |
Rob Pike | c0c3025 | 2008-05-15 15:20:59 -0700 | [diff] [blame] | 28 | case '[': |
| 29 | if a[p] == 0 { |
| 30 | for nest := 1; nest > 0; pc++ { |
| 31 | switch prog[pc+1] { |
| 32 | case ']': |
| 33 | nest--; |
| 34 | case '[': |
| 35 | nest++; |
| 36 | } |
| 37 | } |
| 38 | } |
| 39 | case ']': |
| 40 | if a[p] != 0 { |
| 41 | for nest := -1; nest < 0; pc-- { |
| 42 | switch prog[pc-1] { |
| 43 | case ']': |
| 44 | nest--; |
| 45 | case '[': |
| 46 | nest++; |
| 47 | } |
| 48 | } |
| 49 | } |
| 50 | default: |
| 51 | return; |
| 52 | } |
| 53 | pc++; |
| 54 | } |
Robert Griesemer | 9bc7b08 | 2008-05-08 17:12:15 -0700 | [diff] [blame] | 55 | } |