import java.util.*;
class Solution {
    public int solution(int left, int right) {
        int answer = 0;
        while(left<=right){
            Set<Integer> sarr = new HashSet<>();
            for(int i=1; i<=left/2+1; i++){
                if(left%i==0){
                    sarr.add(i);
                    sarr.add(left/i);
                }
            }
            if (sarr.size() % 2 == 0) {
                answer+=left;
            }else {
                answer-=left;
            }
            left++;
        }
        return answer;
    }
}