2894 - Divisible and Non-divisible Sums Difference.cpp

class Solution 
{
    public:
        int differenceOfSums(int n, int m) 
        {
            int num1 = 0, num2 = 0;

            for(int i=1; i<=n; i++)
            {
                if(i % m) num1 += i;

                else num2 += i;
            }
            return num1 - num2;
        }
};