Meh. Remove the two pushes. Should just be:

while (<LIST1>) {
    ($V1, $V2) = split /\t/;
    $all_V1{$V1}++;
    $all_V2{$V2}++;
}

[download]

... the pushes were left overs from an earlier response I typed up but didn't submit, which used arrays.

I'll correct the code in my original answer too.

In reply to Re^3: Question on loops by tobyink
in thread Question on loops by Bforde

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