function solution(left, right) {
let answer = 0;
for (let i = left; i <= right; i++) {
let count = 0;
for (let j = 1; j <= i; j++) {
if (i % j === 0) {
count++;
}
}
if (count % 2) {
answer -= i;
} else {
answer += i
};
}
return answer;
}