Using regex to add leading zeroes

Posted by hgpc on Stack Overflow See other posts from Stack Overflow or by hgpc
Published on 2010-04-17T16:14:41Z Indexed on 2010/04/17 16:23 UTC
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regex

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language-agnostic

I would like to add a certain number of leading zeroes (say up to 3) to all numbers of a string. For example:

Input: /2009/5/song 01 of 3

Output: /2009/0005/song 0001 of 0003

What's the best way to do this with regular expressions?

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