题解 | #简单密码# #JAVA#

import java.util.*;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String str = in.nextLine();
        String[] KEYS = {"0", "1", "abc", "def", "ghi", "jkl", "mno", "pqrs", "tuv", "wxyz"};
        StringBuilder sb = new StringBuilder();
        for (char c : str.toCharArray()) {
            //数字
            if (Character.isDigit(c)) {
                sb.append(c);
                continue;
            //小写字母
            } else if (Character.isLowerCase(c)) {
                for(int i=0; i<KEYS.length; i++) {
                    if(KEYS[i].contains(String.valueOf(c))){
                        sb.append(i);
                    }
                }
            //大写字母
            } else if (Character.isUpperCase(c)) {
                int index = c - 'A';
                index = (index + 1) % 26;
                sb.append((char)('a' + index));
            }
        }
        System.out.println(sb);
    }
}