Context: I'm working on Project Euler problem 160, which asks you for the last 5 digits of a number, sans any trailing zeros.

My question is this: If I have two greedy constructs in my regex, can I make the latter one be more greedy? What seems to be happening now is that the first construct (Which says "Grab at least 1 but at most 5 digits, greedy) is taking everything it can, but I want the second construct (Which says "Grab as many ending zeros as you can") to have precedence. Here's the regex as is:

$running_total =~ s/(\d{1,5})0*$/$1/;

It's not difficult to change that to be "0 to 4 of any digit, one nonzero digit, and then some zeros," which should fix the problem, but it got me thinking. Is there any way to make that 0* beat up the \d{1,5} and take its lunch money?

In reply to When greedy constructs do battle, can I choose the winner? by amarquis

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