my $mail_id = 'data@mach.com.com';
if($mail_id=~/[A-Za-z0-9._%-]\@[A-Za-z0-9_%-.].[com]/)
{
   print "matched \n";
}
else
{
   print "Not matched \n";
}


##</code><code>##

if($mail_id=~/^[\w\.=-]+@[\w\.-]+\.[\w]{2,3}$/)
{
   print "matched \n";
}
else
{
   print "Not matched \n";
}