프로그래머스(JAVA) : 핸드폰 번호 가리기

 

class Solution {
    public String solution(String phone_number) {
        String answer = "";
        String[] arry = phone_number.split("");
        int x = phone_number.length();
        for(int i = 0; i<x-4 ; i++) {
            arry[i] = "*";
            //System.out.print(arry[i]);
            answer += arry[i];
        }  
        for(int i = x-4; i < x ; i++) {
                //System.out.print(arry[i]);
            answer += arry[i];
        }
 
        return answer;
    }
}