Add pod, error handling for args

1-binary_gap.pl

@@ -8,12 +8,30 @@ use lib "$FindBin::RealBin/lib";
 use lib 'lib';
 use BinaryGap;
 
-use Data::Dumper;
-
-print "Input: " . Dumper($ARGV[0]);
-
 my $number = $ARGV[0];
-my $answer = BinaryGap::solution($number);
-print "Got answer $answer\n";
+if (scalar(@ARGV) != 1) {
+   die "Usage: $0 <integer>\n";
+}
 
-exit;
+my $answer = BinaryGap::solution($number);
+print "The binary gap of $number is $answer\n";
+
+exit;
+
+__END__
+
+=pod
+
+=encoding utf8
+
+=head1 NAME
+
+binary_gap.pl - Find longest sequence of zeros in binary representation of an integer. Script used to call BinaryGap.
+
+=head1 SYNOPSIS
+
+binary_gap.pl <integer>
+
+=head1 DESCRIPTION
+
+This script is used to exercise BinaryGap.pm. It takes one integer as input. It returns the binary gap (longest sequence of zeros) in the binary representation of the input number.

lib/BinaryGap.pm

@@ -61,4 +61,14 @@ sub solution {
    return $max_gap;
 }
 
-1;
+1;
+
+__END__
+
+=pod
+
+=encoding utf8
+
+=head1 NAME
+
+BinaryGap - Find longest sequence of zeros in binary representation of an integer. If there is none, this returns 0.