How to Iterate Through a Vector Without Using Iterators in C++?

In this article, we will learn how to iterate through the vector without using iterator in C++.

The most efficient method to iterate through the vector without using iterator is by using traditional for loop. It accesses all the elements using index starting from 0 to vector size() - 1. Let’s take a look at an example:

#include <bits/stdc++.h>
using namespace std;

int main() {
    vector<int> v = {1, 4, 6, 7, 9};

    // Iterating through vector
    for (int i = 0; i < v.size(); i++)
        cout << v[i] << " ";
  
    return 0;
}

1 4 6 7 9 

Explanation: In the above code, we provide the index in the vector operator[] using traditional for loop to iterate through the vector.

There is also another method to iterate through vector without using iterator in C++.

Using Range Based for Loop

The range-based for loop is a simple and concise way to iterate over the elements of a vector without asking for any iterator or index. (though internally it uses iterators)

#include <bits/stdc++.h>
using namespace std;

int main() {
    vector<int> v = {1, 4, 6, 7, 9};

    // Iterating through vector
    for (auto i : v)
        cout << i << " ";
  
    return 0;
}