challenge #042, raku solutions

2 files changed, 30 insertions, 0 deletions

diff --git a/challenge-042/feng-chang/ch-1.raku b/challenge-042/feng-chang/ch-1.raku
new file mode 100755
index 0000000000..83b4c4a5f6
--- /dev/null
+++ b/challenge-042/feng-chang/ch-1.raku
@@ -0,0 +1,2 @@
+#!/bin/env raku
+(^51).map({ put "Decimal $_ = Octal { .base(8) }" });
diff --git a/challenge-042/feng-chang/ch-2.raku b/challenge-042/feng-chang/ch-2.raku
new file mode 100755
index 0000000000..c5f7106d4a
--- /dev/null
+++ b/challenge-042/feng-chang/ch-2.raku
@@ -0,0 +1,28 @@
+#!/bin/env raku
+
+sub is-balanced(Str:D $s --> Bool) {
+    my Int $i;
+    for $s.comb {
+        when '(' { ++$i }
+        when ')' { --$i; return False if $i < 0; }
+        default  { return False }
+    }
+
+    $i == 0;
+}
+
+multi MAIN('test') {
+    use Test;
+
+    ok is-balanced('()'), '() is good';
+    ok is-balanced('(())'), '(()) is good';
+
+    nok is-balanced(')('), ')( is bad';
+    nok is-balanced('())()'), '())() is bad';
+}
+
+multi MAIN(Str:D $string-of-braces) {
+    given $string-of-braces {
+        put "$_ -{ ' not' if !is-balanced($_) } ok";
+    }
+}