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diff --git a/challenge-042/duane-powell/perl/ch-2.pl b/challenge-042/duane-powell/perl/ch-2.pl
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+++ b/challenge-042/duane-powell/perl/ch-2.pl
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+#!/usr/bin/perl
+use warnings;
+use strict;
+use feature qw( say );
+
+# Write a script to generate a string with random number of ( and ) brackets. Then make the script validate the string if it has balanced brackets
+
+use constant {
+        L_PAREN => '(',
+        R_PAREN => ')',
+};
+
+# generate between 1 and 7 parens, if paren string not passed from cmd line 
+my $paren = shift;
+if ($paren) {
+	say "Given paren string = $paren";
+} 
+else {
+	my $lower_limit = 2;
+	my $upper_limit = 7;
+	my $random_number = int(rand($upper_limit-$lower_limit)) + $lower_limit;
+	for (1 .. $random_number) {
+		# coin toss left or right paren
+		$paren .= (rand() < 0.5) ? L_PAREN : R_PAREN;
+	}
+	say "Random paren string = $paren";
+}
+
+# test if parens are balanced
+my $msg;
+my $paren_count = 0;
+foreach (split(//,$paren)) {
+	$paren_count-- if ($_ eq R_PAREN);
+	$paren_count++ if ($_ eq L_PAREN);
+	if ($paren_count < 0) { 
+		$msg = "Parens are not balanced.";
+		last;
+	}
+}
+$msg = 'Parens are balanced.'   if ($paren_count == 0);
+$msg = 'Parens are not closed.' if ($paren_count  > 0);
+say $msg;
+
+__END__
+
+./ch-2.pl
+random paren string = ()
+Parens are balanced.
+
+./ch-2.pl "((())())"
+Given paren string = ((())())
+Parens are balanced.
+
+./ch-2.pl ")(()()(((()))))"
+Given paren string = )(()()(((()))))
+Parens are not balanced.
+
+./ch-2.pl "((())"
+Given paren string = ((())
+Parens are not closed.
+