#!/usr/bin/perl
# Example 2
# Determine the percentage of GC in a DNA segment

$DNA='CGTGGATATAGGCGGACC';

$GC = ($DNA =~ tr/GCgc//);
$perGC = int(($GC/length($DNA))*100);

print "\n";
print "The GC content is $perGC percent.";

exit;