CPP

c++ Sum of all the factors of a number

// Simple C++ program to
// find sum of all divisors
// of a natural number
#include<bits/stdc++.h>
using namespace std;
  
// Function to calculate sum of all
//divisors of a given number
int divSum(int n)
{
    if(n == 1)
      return 1;
 
    // Sum of divisors
    int result = 0;
  
    // find all divisors which divides 'num'
    for (int i = 2; i <= sqrt(n); i++)
    {
        // if 'i' is divisor of 'n'
        if (n % i == 0)
        {
            // if both divisors are same
            // then add it once else add
            // both
            if (i == (n / i))
                result += i;
            else
                result += (i + n/i);
        }
    }
  
    // Add 1 and n to result as above loop
    // considers proper divisors greater
    // than 1.
    return (result + n + 1);
}
  
// Driver program to run the case
int main()
{
    int n = 30;
    cout << divSum(n);
    return 0;
}