DB<90> sub format_n { my $n= shift; printf "%b" x $n ." ", splice @_, 0, $n while @_ }

  DB<91> format_n 3,(1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0)
101 100 101 010
  DB<92> format_n 4,(1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0)
1011 0010 1010
  DB<93> format_n 5,(1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0)
10110 01010 10000