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;
}
}