题解 | 字符串加解密

重点：

1. 牛马活，纯粹的匹配赋值
2. 需要仔细写
3. 还有一些其他的版本：更简洁
1. 字母表直接写出来，一一对应即可
2. 使用Charactor的静态方法做计算等

import java.util.Scanner;

// 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);
        char[] enCharArr = in.next().toCharArray();
        char[] deCharArr = in.next().toCharArray();

        for (int i = 0; i < enCharArr.length; i++) {
            char c = enCharArr[i];
            char tmp = 0;
            if (c == 'Z') {
                tmp = 'a';
            }
            if (c == 'z') {
                tmp = 'A';
            }
            if (c >= 'A' && c < 'Z') {
                tmp = (char)(c + 33);
            }
            if (c >= 'a' && c < 'z') {
                tmp = (char)(c - 31);
            }
            if (c >= '0' && c <= '8') {
                tmp = (char)(c + 1);
            }
            if (c == '9') {
                tmp = '0';
            }
            enCharArr[i] = tmp;
        }
        System.out.println(new String(enCharArr));

        for (int i = 0; i < deCharArr.length; i++) {
            char c = deCharArr[i];
            char tmp = 0;
            if (c == 'a') {
                tmp = 'Z';
            }
            if (c == 'A') {
                tmp = 'z';
            }
            if (c >= 'b' && c <= 'z') {
                tmp = (char)(c - 33);
            }
            if (c >= 'B' && c <= 'Z') {
                tmp = (char)(c + 31);
            }
            if (c >= '1' && c <= '9') {
                tmp = (char)(c - 1);
            }
            if (c == '0') {
                tmp = '9';
            }
            deCharArr[i] = tmp;
        }
        System.out.println(new String(deCharArr));
    }
}