my own struct on vector

6 int main()
  7 {
  8   struct nodeType
  9   {
 10     int a, b;
 11   };
 12   list<nodeType> x;
 13   return 0;
 14 }
(2 / 5): error: `main()::nodeType' uses local type `main()::nodeType'

what's wrong with my code? how should I modify?