There's no reason to work hard to set the values in the hash to ones, leave them undefined and use exists() within the grep{}. Also there is no reason to push the elements into the @intersection, just assign them.

my %hash1;
@hash1{@array1} = ();
my @intersection = grep {exists $hash1{$_} } @array2;

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Jenda
Enoch was right!
Enjoy the last years of Rome.

In reply to Re^2: Logical operations on arrays by Jenda
in thread Logical operations on arrays by ronmrdechai

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