sub natural_sort {
    return @_ if @_ < 2;
    my @words = @_.map({ .lc });
    my $index = 0;
    for @words {
       .=subst(/(\d+)/, -> $/{ sprintf( "%s%c%s", 0, $0.chars, $0) }, :g);
       $_ ~= ' ' ~ $index++;
    };
    return @_[@words.sort.map({@(split(' ',$^_))[*-1]})];
}