if (my($year, $mon, $day, $hour, $min) = $file =~ /Rajesh\.([0-9]{2})([0-9]{2})([0-9]{2})([0-9]{2})([0-9]{2})/) {
    my $unixtime = mktime(0, $min, $hour, $mon - 1, $year + 100, 0, 0);
    ...
}