The each() function only has ONE iterator per hash. You'll have to use keys(). 
for my $k1 (keys %hash) {
  for my $k2 (keys %hash) {
    next if $k1 eq $k2 and $skip_identical_keys;
    $cart_prod{$k1}{$k2} = ...;
  }
}

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Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re: What is wrong with the code ? by japhy
in thread What is wrong with the code ? by vennirajan

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