foo.cpp: In function 'int main()':
foo.cpp:17:24: error: cannot convert 'std::set<int>::iterator {aka std::_Rb_tree_const_iterator<int>}' to 'int' in initialization
foo.cpp:18:24: error: cannot convert 'std::set<int>::iterator {aka std::_Rb_tree_const_iterator<int>}' to 'int' in initialization