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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:16:40 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:16:40 +0000
commit47ab3d4a42e9ab51c465c4322d2ec233f6324e6b (patch)
treea61a0ffd83f4a3def4b36e5c8e99630c559aa723 /test/turing.go
parentInitial commit. (diff)
downloadgolang-1.18-upstream.tar.xz
golang-1.18-upstream.zip
Adding upstream version 1.18.10.upstream/1.18.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'test/turing.go')
-rw-r--r--test/turing.go59
1 files changed, 59 insertions, 0 deletions
diff --git a/test/turing.go b/test/turing.go
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--- /dev/null
+++ b/test/turing.go
@@ -0,0 +1,59 @@
+// run
+
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test simulating a Turing machine, sort of.
+
+package main
+
+// brainfuck
+
+var p, pc int
+var a [30000]byte
+
+const prog = "++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>.!"
+
+func scan(dir int) {
+ for nest := dir; dir*nest > 0; pc += dir {
+ switch prog[pc+dir] {
+ case ']':
+ nest--
+ case '[':
+ nest++
+ }
+ }
+}
+
+func main() {
+ r := ""
+ for {
+ switch prog[pc] {
+ case '>':
+ p++
+ case '<':
+ p--
+ case '+':
+ a[p]++
+ case '-':
+ a[p]--
+ case '.':
+ r += string(a[p])
+ case '[':
+ if a[p] == 0 {
+ scan(1)
+ }
+ case ']':
+ if a[p] != 0 {
+ scan(-1)
+ }
+ default:
+ if r != "Hello World!\n" {
+ panic(r)
+ }
+ return
+ }
+ pc++
+ }
+}