Thanks a lot. By the way I think DateTime::Format::Strptime module is not coming with the Perl default package.

:) Correct, I just checked :) $ corelist DateTime

DateTime::Format::Strptime

Data for 2015-04-20
DateTime was not in CORE (or so I think)

Data for 2015-04-20
DateTime::Format::Strptime was not in CORE (or so I think)
[download]

But this was never important to me :) I was mostly checking tye's solution for correctness ;)

Yes, even you can use CPAN, A Guide to Installing Modules, Top 11 (GOOD) reasons not to use someone else's Modules, Top Seven (Bad) Reasons Not To Use Modules