A very elegant and general solution: use Algorithm::Combinatorics qw/.../;

For example:

use Algorithm::Combinatorics qw/combinations/;
@names = ('rita', 'sue','bob', 'daisy');
my $r=combinations(\@names,2);
while(my $res=$r->next){
print "@$res\n";
}
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There are several other combinatorical functions to replace all these foreach loops...