Remember that you always have * and +.

You need the use of * when you want to find 0 or more elements of the pattern ( say.. \d in your example ) and + if you want to find 1 or more elements of your pattern.

So in your program, you're trying to find a \d everytime, so.. if you have \d*, you're telling perl that your regexp might find 0 or more numbers.

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