http://www.perlmonks.org?node_id=903240


in reply to weird array processing question

It almost sounds like you want something like this (warning: destructive to the array since it removes items off the beginning because they've already been compared):

my @array = ( 1, 2, 3, 4, 1, 2, 3 ); my $matches = 0; while( @array ) { my $candidate = shift @array; for( @array ) { $matches++ if $candidate == $_ } } print "Got $matches matches\n";

Update: I like toolic's approach below better as it solves the problem "does my list have more than three duplicates of any one element" without as many comparisons; original question was fuzzy so . . .

The cake is a lie.
The cake is a lie.
The cake is a lie.