Does a vector sort invalidate iterators?

Question

 std::vector<string> names;
 std::vector<string>::iterator start = names.begin();
 std::vector<string>::iterator end = names.end();
 sort (start,end);
 //are my start and end valid at this point?
 //or they do not point to front and tail resp?

Answer 1

According to the C++ Standard §23.1/11:

Unless otherwise specified (either explicitly or by defining a function in terms of other functions), invoking a container member function or passing a container as an argument to a library function shall not invalidate iterators to, or change the values of, objects within that container.

§25.3 "Sorting and related operations" doesn't specify that iterators will be invalidated, so iterators in the question should stay valid.

Answer 2

They still point to the beginning and end. The values in those slots of the vector have probably changed, but the storage location in which each resides remains the same.