and what happens when the number of elements increases? This code is O(n2) which doesn't scale at all well. Better is something like:

    my %hits;
    
    ++$hits{$_} for @a1;

    my @matched = grep {exists $hits{$_}} @a2;

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True laziness is hard work

In reply to Re^2: Array comparison using perl by GrandFather
in thread Array comparison using perl by ajguitarmaniac

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