Issue using vector of list

I need to be able to insert a list into a vector at a specific location. However, I'm not able to do it. Vector need to know the size of its element but the size of the list can't be determined. How can I resolve this?

I keep getting segfault

std::list<std::string> mylist;
mylist.push_front(query.s);
A.insert(A.begin()+h, mylist);