rethaew want[s] to do it "without looping through each hash and counting." No, I don't think that's possible.

I agree. Even a solution like
    my $age12 = grep $_->{age} == 12, values %hoh;
implicitly loops through the hash. rethaew will have to wait for the arrival of the personal desktop quantum computer to solve the problem without looping.

In reply to Re^2: Find number of unique values in hash by AnomalousMonk
in thread Find number of unique values in hash by rethaew

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