Question

template<class T>     class mStack     {     private:        vector<T> a;         vector<T>::iterator top;     public:        void push(T);        T pop();        mStack();        void printStack(); }; 

The code with above class is not getting compiled… why? What is the problem? The compiler says ‘expected ; above top’.

Answer 1

You need a typename:

typename vector<T>::iterator top; 

This reassures the compiler thar vector<T> really is a type. For a discussion of this and other template gotchas, see the C++ FAQ.