Here is one solution: 
s/(10*1)/1 x length($1)/eg;

[download]
Note that you might want to change the * to a + depending on what you want to happen should the ones be right next to each other. updatewording was "change the * to a star", thanks L~R

-enlil

In reply to Re: Creating a fill-in regexp by Enlil
in thread Creating a fill-in regexp by jpfarmer

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