题目：

题解：

class Solution {
public:
    bool isUgly(int n) {
        if (n <= 0) {
            return false;
        }
        vector<int> factors = {2, 3, 5};
        for (int factor : factors) {
            while (n % factor == 0) {
                n /= factor;
            }
        }
        return n == 1;
    }
};