What are some examples of iterators in C++?

What are some examples of iterators in C++?

In C++, iterators are used to traverse through containers. For example, you can use a vector iterator like this:

#include <iostream>
#include <vector>

int main() {
    std::vector<int> vec = {1, 2, 3, 4, 5};
    for (std::vector<int>::iterator it = vec.begin(); it != vec.end(); ++it) {
        std::cout << *it << " ";
    }
    return 0;
}

Can you explain how the iterator works in this example?

Sure! In this example, vec.begin() returns an iterator pointing to the first element of the vector, and vec.end() points to one past the last element. The loop continues until the iterator reaches the end, and *it dereferences the iterator to access the value.

What other types of iterators are there in C++?

C++ has several types of iterators, including:

1. Input Iterators: Read elements from a container.
2. Output Iterators: Write elements to a container.
3. Forward Iterators: Can read and write, and can be incremented.
4. Bidirectional Iterators: Can be incremented and decremented.
5. Random Access Iterators: Can access elements at any position directly.

Can you give an example of a random access iterator?

Certainly! A common example of a random access iterator is the one used with arrays or vectors. Here's a simple example:

#include <iostream>
#include <vector>

int main() {
    std::vector<int> vec = {10, 20, 30, 40, 50};
    std::cout << vec[2] << std::endl; // Accessing the third element directly
    return 0;
}