외계행성의 나이

public class Solution {
    public String solution(int age) {
        String ageStr = Integer.toString(age);
        String result = ageStr.replace('0', 'a')
                .replace('1', 'b')
                .replace('2', 'c')
                .replace('3', 'd')
                .replace('4', 'e')
                .replace('5', 'f')
                .replace('6', 'g')
                .replace('7', 'h')
                .replace('8', 'i')
                .replace('9', 'j');
        return result;
    }
}