Hi Monks

Sorry if my question is a little basic. I know some basic pattern matching, and have tried the tutorials section, but I'm still having a little trouble with the following task.

I have a load of date/time strings that have the following format:
mmm d{d} yyyy hh:mm:ss:sss{AM/PM}

eg. Oct 16 2004 11:09:19:943AM (example 1)
or Mar 3 2007 10:30:31:170PM (example 2)

What I want to do is to extract the day, month and year, and stick them together in the format yyyymmdd so I can sort by date easily. So for the above examples you'd get:
20041016 and
20070303

I've tried the following bit of code:

            if ($data=~/(\D{3}) *?(\d{1,2}) *?(\d{4})/) # i.e. look fo
+r 3 non-digits, then any number of spaces, then either 1 or two digit
+s, then any number of spaces, then 4 digits. (I wasn't sure how many 
+spaces separated each part.)
            {
            $month=    $datehash{$1},br; # datehash is a lookup for th
+e month                $day=$2;
            if ($day=~/\d{1}/)
            {
            $day='0'.$day; # i.e. add a '0' in front of days consistin
+g of 1 digit, so 16 stays as 16, but 1 turns into 01            } 
            $year=$3;
            $sortingdate=join '', $year, $month, $day;
            }

[download]
Now this works for example 2 (I do get 20070303), but not for example 1: for some reason I get 1016 instead of 20041016. Why?

In reply to Pattern matching for extracting dates by Anonymous Monk

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