C语言 | Leetcode C语言题解之第507题完美数-题解：

bool checkPerfectNumber(int num){
    if (num == 1) {
        return false;
    }

    int sum = 1;
    for (int d = 2; d * d <= num; ++d) {
        if (num % d == 0) {
            sum += d;
            if (d * d < num) {
                sum += num / d;
            }
        }
    }
    return sum == num;
}