题解 | #字符串加解密#

实际上如果ASCII记得很熟悉的话，这道题算不上中等难度：

package huawei;

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);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNext()) { // 注意 while 处理多个 case
            String a = in.nextLine();
            String b = in.nextLine();

            char[] line1 = a.toCharArray();
            char[] line2 = b.toCharArray();

            StringBuilder stringBuilder1 = new StringBuilder();
            for (char c : line1) {
                if (c >= 65 && c < 90) {
                    stringBuilder1.append(Character.toLowerCase((char) (c + 1)));
                } else if (c == 90) {
                    stringBuilder1.append("a");
                } else if (c >= 97 && c < 122) {
                    stringBuilder1.append(Character.toUpperCase((char) (c + 1)));
                } else if (c == 122) {
                    stringBuilder1.append("A");
                } else if (c >= 48 && c < 57) {
                    stringBuilder1.append(Character.toLowerCase((char) (c + 1)));
                } else if (c == 57) {
                    stringBuilder1.append("0");
                } else {
                    stringBuilder1.append(Character.toUpperCase(c));
                }
            }

            StringBuilder stringBuilder2 = new StringBuilder();
            for (char c : line2) {
                if (c > 65 && c <= 90) {
                    stringBuilder2.append(Character.toLowerCase((char) (c - 1)));
                } else if (c == 65) {
                    stringBuilder2.append("z");
                } else if (c > 97 && c <= 122) {
                    stringBuilder2.append(Character.toUpperCase((char) (c - 1)));
                } else if (c == 97) {
                    stringBuilder2.append("Z");
                } else if (c > 48 && c <= 57) {
                    stringBuilder2.append(Character.toLowerCase((char) (c - 1)));
                } else if (c == 48) {
                    stringBuilder2.append("9");
                } else {
                    stringBuilder2.append(Character.toUpperCase(c));
                }
            }

            System.out.println(stringBuilder1);
            System.out.println(stringBuilder2);
        }
    }
}