[Programmers] Lv1: 핸드폰 번호 가리기(12948)

문제

- 링크: https://school.programmers.co.kr/learn/courses/30/lessons/12948

 

풀이

class Solution {
    public String solution(String phone_number) {
        String answer = "";
        for (int i = 0; i < phone_number.length() - 4; ++i) {
            answer += "*";
        }
        for (int i = phone_number.length() - 4; i < phone_number.length(); ++i) {
            answer += phone_number.charAt(i);
        }
        return answer;
    }
}