[프로그래머스] 가운데 글자 가져오기

class Solution {
    public String solution(String s) {
        String answer = "";
        int length = s.length();
        if(length%2==0){
            answer = s.substring((length/2)-1, (length/2)+1);
        }else{
            answer = s.substring((length/2), (length/2)+1);
        }
        return answer;
    }
}