Try: 
foreach $k (keys %hash){
delete ($hash{$k}) unless exists $end{$k};
}

[download]

You were using $_ as the key to %end. You have not set $_ in the code you posted so it is unlikely to have a value that you want. This should clear the error.

In reply to Re: Delete keys in hash if they exist in another hash by inman
in thread Delete keys in hash if they exist in another hash by tgolf4fun

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