The **`distance()` function** in C++ helps find the distance between two iterators. In other words, we can use this function to calculate the number of elements present between the two iterators. This function is available in the `<iterator>` header file.

#   
#  Parameters
The `distance()` function accepts the following parameters.

* **`first`:** This is an iterator that points to the initial position of the array or vector.

* **`last`:** This is an iterator that points to the last position of the array or vector.

#   
## Return
The `distance()` function returns the number of elements between `first` and `last`.

##  
## Code
Let’s look at the code now.



#include <iostream>
#include <vector>
#include <list>
using namespace std;

int main () {
  vector<int> vec = {1,2,3,4,5,6,7,8,9,10};

  int dist = distance(vec.begin(), vec.end());

  cout << "The distance is: " << dist;

  return 0;
}

#   
## Explanation
* From _lines 1 to 3_, we import the required header files.
* In _line 7_, we create a vector that contains some integer values.
* In _line 9_, we call the `distance()` function and pass the two iterators.
* In _line 11_, we print the number of elements present between the two iterators.

What is the distance() function in C++?

Calculates the number of elements between two iterators in an array or vector.