[프로그래머스][JAVA] 시저 암호 (문자열)

class Solution {
    public String solution(String s, int n) {
        char[] chArr = s.toCharArray();
        
        for(int i=0; i<chArr.length; i++){
            // if('a'<= chArr[i] && chArr[i]<='z'){
            if(Character.isLowerCase(chArr[i])){
                chArr[i] = (char)((chArr[i]-'a'+n)%26 + 'a');
 
            }
            else if(Character.isUpperCase(chArr[i])){
                chArr[i] = (char)((chArr[i]-'A'+n)%26 + 'A');
            }
            
            System.out.print(chArr[i]);
            
        }
       
        
        return String.valueOf(chArr);
    }
}