use Time::Local;

  my $time1 = '010101112245';
  my $time2 = '010101114556';

  foreach ($time1, $time2){
    my @t = $time1 =~ /(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)/;
    @t = reverse @t;
     $_ = timelocal(@t);
  }

 print "Difference is: ", ($time1 -$time2), "\n";