Iterators

Iterator is a pointer to the container.

vector<int>::iterator it = v.begin(); 
// points to the first element of the vector

for (int i = 0; i < 5; i++)
    cout << *(it + i) << " ";

for (it = v.begin(); it != v.end(); it++)
    cout << *it << " ";

There is significant difference between operations on iterators...

(it + 1) points to the next location in the memory
- (it + 1) is useful only when the memory allocation of a container is contiguous, Like in vectors
(it++) points to the next element in the container
- In non-contiguous memory allocated Containers, (it + 1) may point to undefined memory.

Last modified: 08 February 2026