vector.rbegin()

The expression vector.rbegin() in C++ returns a reverse iterator pointing to the last element of the vector. Here is a step-by-step explanation of this expression:

1. vector: This refers to the name of the vector object you are working with. Replace vector with the actual name of your vector.

2. .: The dot operator is used to access the member functions and variables of the vector object.

3. rbegin(): This is a member function of the vector class that returns a reverse iterator pointing to the last element of the vector. The reverse iterator allows you to iterate over the vector in reverse order.

By using vector.rbegin(), you can access the last element of the vector and perform operations on it or iterate over the vector in reverse order using a loop or other iterator functions.