iterator erase(iterator it);
iterator erase(iterator first, iterator last);The first member function removes the element of the controlled sequence pointed to by it. The second member
function removes the elements of the controlled sequence in the range [first, last). Both return an iterator that
designates the first element remaining beyond any elements removed, or end() if no such element exists.
Erasing N elements causes N destructor calls. No reallocation occurs, so iterators and references become invalid only
for the erased elements.