What are STL iterators in C++?

What are STL iterators in C++?

STL iterators are objects that allow you to traverse the elements of a container in C++. They provide a way to access elements without exposing the underlying structure.

Can you explain the different types of iterators?

Sure! There are several types of iterators in STL: input iterators, output iterators, forward iterators, bidirectional iterators, and random access iterators. Each type has different capabilities.

How do I use a vector iterator?

To use a vector iterator, you can declare it like this: std::vector<int>::iterator it = vec.begin();. You can then increment it to traverse the vector.

What is the difference between begin() and end()?

begin() returns an iterator to the first element, while end() returns an iterator to one past the last element. The end() iterator is not dereferenceable.

Can you give me an example of using iterators in a loop?

Certainly! Here's a simple example:

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

This will print all the elements in the vector.