[프로그래머스] 콜라츠 추측

class Solution {
    public int solution(int num) {
        long n = num;
        int answer = 0;
        
        while (n > 1) {
            if (answer == 500) return -1;
            if (n % 2 == 0) {
                n /= 2;
                answer++;
            } else {
                n = n * 3 + 1;
                answer++;
            }
        }
        return answer;
    }
}