$ perl -le'

my @select = (
    [ "AAA", "A Description", 1, 0 ],
    [ "BBB", "B Description", 0, 0 ],
    [ "CCC", "C Description", 0, 0 ],
    [ "DDD", "D Description", 1, 0 ],
    [ "EEE", "E Description", 1, 0 ],
    );

my $length = grep $select[ $_ ][ 2 ], 0 .. $#select;

print "Selective Length : $length";
'
Selective Length : 3
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