@a = qw|Bob Sue|;
@b = qw|Ted Mary|;
@c = qw|Biff Muffy|;

my @all_combos;
for my $a (@a) {
   for my $b (@b) {
      for my $c (@c) {
         push @all_combos, "$a has a meeting with $b and $c\n";
      }
   }
}