DB<1>  @array = qw/1 1 1 1 1 1 1 1 1 1 4 4 4 4 4 4 4 4 4 4 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3/;

  DB<2> while (@array) { $sum = 0; $sum += shift @array for 1..10; print "$sum\n";};
10
40
20
30