gistfile1.txt

sub Pm's-Q2 (@a) {
    my @indices := (^(2*@a)).map: {
        $_ %% 2 , ($_/2).floor
    }
    @indices.map: -> [Bool $switch, Int $index] {
        $switch ?? $index !! @a[$index, $index]
    }
}

say Pm's-Q2(my @ = "a"..* )[^100].perl