124 나라의 숫자 (자바)

package prog;

public class 일이사_나라의_숫자 {
    public static void main(String[] args) {
        일이사_나라의_숫자_Solution s= new 일이사_나라의_숫자_Solution();
        System.out.println(s.solution(1));
        System.out.println(s.solution(2));
        System.out.println(s.solution(3));
        System.out.println(s.solution(4));


    }
}

class 일이사_나라의_숫자_Solution{
    public String solution(int n) {
        StringBuilder answer = new StringBuilder();
        while(n!=0){
            if(n%3!=0){

                answer.append(n%3);
            }
            else{

                answer.append(4);
                n--;
            }
            n=n/3;
        }
        return answer.reverse().toString();

    }
}