my @a = (1..16);
my $kid_size = 3;
my $num = int(@a/$kid_size);
my @b;

foreach my $i (0..$num-1) {
   $b[$i] = [splice @a,0,$kid_size];
}
$b[$num] = [@a];

foreach my $i (0..$num) {
   print "b($i): ", join(",", @{$b[$i]}), "\n";
}
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