Divisible and Non-divisible Sums Difference.cpp

class Solution {
public:
    int differenceOfSums(int n, int m) {
        int notDiv = 0, ans = 0, div = 0;
        for(int i=1; i<=n; i++){
            if(i%m != 0) notDiv += i;
            else div += i;
        }
        return notDiv - div;
    }
};