type
  info=record
         link:array[1..100]of integer;
         position:integer;
         count:integer;
       end;
label 99;
var
  n,i,j,temp,sum:integer;
  a:array[1..100]of info;
begin
  {assign(input,'input.txt');
  assign(output,'output.txt');
  rewrite(output);
  reset(input);  }
  readln(n);
  for i:=1 to n do
     begin
         read(temp);
         j:=0;
         while temp<>0 do
             begin
                 a[i].link[j]:=temp;
                 inc(j);
                 read(temp);
             end;
         dec(j);

         a[i].count:=j;
         if a[i].count=0 then
            goto 99;
         a[i].position:=0;
         readln;
     end;
   a[1].position:=1;
   sum:=1;
   for i:=1 to a[1].count do
      a[a[1].link[i]].position:=2;
   for i:=2 to n do
      begin
         if a[i].position=0 then
            begin
               a[i].position:=1;
               inc(sum);
               for j:=1 to a[i].count do
                  a[a[i].link[j]].position:=2;
            end;
      end;
   writeln(sum);
   writeln(output,sum);
   for i:=1 to n do
     if a[i].position=1 then
        begin
           write(i);
           write(' ');
        end;
   {close(input);
   close(output);}
99: writeln(0);
   readln;
end.