http://www.perlmonks.org?node_id=418775


in reply to Re^2: Comparison by position and value
in thread Comparison by position and value

I don't see your problem:

_8__3__19 v 48____7__ ? 0 ^ _8__3__19 v 4_8___7__ ? 1 _8__3__19 v 48_____7_ ? 0 ^ ^

For these strings at least, the result is 0 iff there is a clash of two digits somewhere.