How to find the sum of elements of an Array using STL in C++?

Given an array arr[], find the sum of the elements of this array using STL in C++.

Example:

Input: arr[] = {1, 45, 54, 71, 76, 12}
Output: 259

Input: arr[] = {1, 7, 5, 4, 6, 12}
Output: 35

Approach: Sum can be found with the help of accumulate() function provided in STL.

Syntax:

accumulate(first_index, last_index, initial value of sum);

Below is the implementation of the above approach:

// C++ program to find the sum
// of Array using accumulate() in STL

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

int main()
{
    // Get the array
    int arr[] = { 1, 45, 54, 71, 76, 12 };

    // Compute the sizes
    int n = sizeof(arr) / sizeof(arr[0]);

    // Print the array
    cout << "Array: ";
    for (int i = 0; i < n; i++)
        cout << arr[i] << " ";

    // Find the sum
    cout << "\nSum = "
         << accumulate(arr, arr + n, 0);
    return 0;
}

Output:

Array: 1 45 54 71 76 12 
Sum = 259