7. Write a function with one integer parameter that will return the sum of the divisors of its argument.

[Note: Explanation of the program code is provided within the comments.]

Program code:

//including header files

#include<bits/stdc++.h>

using namespace std;

// Function to calculate sum of all the divisors

int divSum(int num)

{

    //declaring required variables

    int result = 0;

    // find all divisors which divides 'num'

    //for loop

    for (int i=2; i<=sqrt(num); i++)

    {

        // if 'i' is divisor of 'num'

        if (num%i==0)

        {

            // if both divisors are same then adding it only once

            if (i==(num/i))

                result += i;

            //otherwise

            else

            //adding here

                result += (i + num/i);

        }

    }

    // Adding 1 to the result as 1 is also a divisor

    return (result + 1);

}

// main method

int main()

{

    //declaring required variable

    int num = 12;

    //calling function and displaying results

    cout << "Sum of all divisors of "<<num<<" is : " <<divSum(num);

    return 0;

} //end of main method