What are C++ STL container iterators?

Can you explain what C++ STL container iterators are?

Sure! C++ STL (Standard Template Library) container iterators are objects that allow you to traverse the elements of a container, like vectors or lists, without exposing the underlying structure.

How do I use iterators with a vector?

You can use iterators with a vector by calling the begin() and end() methods. For example:

std::vector<int> vec = {1, 2, 3, 4};
for (auto it = vec.begin(); it != vec.end(); ++it) {
    std::cout << *it << ' ';
}

What are the different types of iterators available?

There are several types of iterators in C++, including:

1. Input iterators
2. Output iterators
3. Forward iterators
4. Bidirectional iterators
5. Random access iterators Each type has different capabilities and use cases.

Can you give an example of a bidirectional iterator?

Certainly! A bidirectional iterator allows you to traverse a container in both directions. For example, you can use a std::list:

std::list<int> myList = {1, 2, 3};
auto it = myList.begin();
while (it != myList.end()) {
    std::cout << *it << ' ';
    ++it;
}
--it; // Move back
std::cout << *it; // Outputs the last element