{
   my @points_str;

   sub st3_look {
      my $cells = shift;
      unless (@points_str) {
         for my $p (@points) {
            push @points_str, join(':', @$p);
         }
      }
      for my $p (@points_str) {
         exists $cells->{$p} or die;
      }
      exists $cells->{'notfound'} and die;
      exists $cells->{'notfound2'} and die;
      exists $cells->{'notfound3'} and die;
   }
}

my $str_ref = str_hash();
my $st2_ref = str_hash();
my $st3_ref = str_hash();
my $big_ref = big_hash();
my $pak_ref = pak_hash();
my $mat_ref = mat_hash();

timethese 200000, {
   Str => sub { str_look($str_ref) },
   St2 => sub { st2_look($st2_ref) },
   St3 => sub { st3_look($st3_ref) },
   Big => sub { big_look($big_ref) },
   Pak => sub { pak_look($pak_ref) },
   Mat => sub { mat_look($mat_ref) },
};