template <typename ElementType, typename CompareClass>

struct Delegate {

        virtual bool geef(const ElementType &element){

                pair <set<ElementType, CompareClass>::iterator, bool> ret;  //this is line 196

                ret = elements.insert(element); //197

                return (ret.second); //198

        }

        

        virtual void output() = 0;

        

        set<ElementType, CompareClass> elements;

};



struct ArtiestenPrinter : public Delegate<Lied, LiedCompare> {

        virtual bool geef(const Lied &lied){

                bool nieuwElement = Delegate<Lied, LiedCompare>::geef(lied); // 210

                if (nieuwElement) {

                        cout << lied.artiest;

                }

                return nieuwElement;

        }

        

        virtual void output(){

                for(set<Lied, LiedCompare>::iterator it = elements.begin();

                        it != elements.end();

                        it++){

                        

                        cout << it->artiest << endl;

                }

        }

};

196: error: type/value mismatch at argument 1 in template parameter list for 'template<class _T1, class _T2> struct std::pair'

196: error:   expected a type, got 'std::set<ElementType,CompareClass,std::allocator<_CharT> >::iterator'

196: error: invalid type in declaration before ';' token

198: error: request for member 'second' in 'ret', which is of non-class type 'int'

210:   instantiated from here

197: error: cannot convert 'std::pair<std::_Rb_tree_const_iterator<Lied>, bool>' to 'int' in assignment