Further to GrandFather's remarks:   The regex /^[5]+$/ does not match the string '503009496', but is there any other string it would match? What about the strings 

5
55
555
555555555

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If you find some strings that match, how would they and the strings you know do not match interact with the regex components mentioned by GrandFather? Please see perlre, perlretut, perlrequick and perlreref.

Give a man a fish:  <%-{-{-{-<

In reply to Re: Need a regular expression to check the first digit by AnomalousMonk
in thread Need a regular expression to check the first digit by chandantul

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