Merge pull request #1114 from waltman/branch-for-challenge-042

Branch for challenge 042

2 files changed, 32 insertions, 0 deletions

diff --git a/challenge-042/walt-mankowski/perl5/ch-1.pl b/challenge-042/walt-mankowski/perl5/ch-1.pl
new file mode 100644
index 0000000000..28ba8c4459
--- /dev/null
+++ b/challenge-042/walt-mankowski/perl5/ch-1.pl
@@ -0,0 +1,5 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+
+printf "Decimal %d = Octal %o\n", $_, $_ for 0..50;
diff --git a/challenge-042/walt-mankowski/perl5/ch-2.pl b/challenge-042/walt-mankowski/perl5/ch-2.pl
new file mode 100644
index 0000000000..04d4222e3e
--- /dev/null
+++ b/challenge-042/walt-mankowski/perl5/ch-2.pl
@@ -0,0 +1,27 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+use feature qw(:5.30);
+use experimental qw(signatures);
+
+my $MAX_LEN = 10;
+
+# return a random string of parens of length $len
+sub rand_str($len) {
+    return join '', map { rand(2) < 1 ? '(' : ')' } 1..$len;
+}
+
+# return true if the parens are balanced, else false
+sub balanced($s) {
+    my $cnt = 0;
+    for my $c (split //, $s) {
+        $cnt += $c eq '(' ? 1 : -1;
+        return 0 if $cnt < 0; # too many right parens
+    }
+    return $cnt == 0;
+}
+
+for (1..100) {
+    my $rs = rand_str(int(rand($MAX_LEN)) + 1);
+    say $rs, balanced($rs) ? " - OK" : " - NOT OK";
+}