题解 | 字符串加解密

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        char[] chars1 = sc.nextLine().toCharArray();
        char[] chars2 = sc.nextLine().toCharArray();
        for (int i = 0; i < chars1.length; i++) {
            if (chars1[i] <= 'z' && chars1[i] >= 'a') {
                if (chars1[i] == 'z') {
                    chars1[i] = 'a';
                } else {
                    chars1[i] = (char)(chars1[i] + 1);
                }
                chars1[i] = (char) (chars1[i] - 32);
                continue;
            }
            if (chars1[i] <= 'Z' && chars1[i] >= 'A') {
                if (chars1[i] == 'Z') {
                    chars1[i] = 'A';
                } else {
                    chars1[i] = (char)(chars1[i] + 1);
                }
                chars1[i] = (char) ((int)chars1[i] + 32);
                continue;
            }
            if (chars1[i] <= '9' && chars1[i] >= '0') {
                if (chars1[i] == '9') {
                    chars1[i] = '0';
                } else {
                    chars1[i] = (char)(chars1[i] + 1);
                }
            }
        }
        System.out.println(chars1);
        for (int i = 0; i < chars2.length; i++) {
            if (chars2[i] <= 'z' && chars2[i] >= 'a') {
                if (chars2[i] == 'a') {
                    chars2[i] = 'z';
                } else {
                    chars2[i] = (char)(chars2[i] - 1);
                }
                chars2[i] = (char) (chars2[i] - 32);
                continue;
            }
            if (chars2[i] <= 'Z' && chars2[i] >= 'A') {
                if (chars2[i] == 'A') {
                    chars2[i] = 'Z';
                } else {
                    chars2[i] = (char)(chars2[i] - 1);
                }
                chars2[i] = (char) ((int)chars2[i] + 32);
                continue;
            }
            if (chars2[i] <= '9' && chars2[i] >= '0') {
                if (chars2[i] == '0') {
                    chars2[i] = '9';
                } else {
                    chars2[i] = (char)(chars2[i] - 1);
                }
            }
        }
        System.out.println(chars2);
    }
}