Hello monks!
I have 4 hashes and I want to check which keys from a 5th hash are NOT present at any of the 4 hashes. I tried:
foreach $a(keys %test_hash)
{
    if(not exists($hash1{$a}) && not exists($hash2{$a}) && not exists(
+$hash3{$a}) && not exists($hash4{$a}))
    {
        print  $test_hash{$a};
    }
}

[download]

but it didn;t work, since I got a list of keys that were supposedly only present in the 5th hash (test_hash), but when I checked 1-2 by hand, I found out that they were also present in one or more of the other hashes as well.
What m I doing wrong here?
Thanks!

In reply to Check if a key exists in several hashes at once by Anonymous Monk

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