$ perl -Mstrict -Mwarnings -le '
    my $x = "a b c d";
    my (undef, undef, $c, $d) = split /\s+/ => $x;
    print "$c $d";
'
c d

##</code><code>##

$ perl -Mstrict -Mwarnings -le '
    my $x = "a b c d";
    my ($c, $d) = (split /\s+/ => $x)[2,3];
    print "$c $d";
'
c d