题解 | #字符串加解密#

import java.util.; import java.io.; import java.util.stream.*;

public class Main{

public static void main(String[] args){

    InputStreamReader reader =   new InputStreamReader(System.in);

    try(BufferedReader br = new BufferedReader(reader)){

        String origin = br.readLine();
        String encrypt = br.readLine();
        char[] origin_chars = origin.toCharArray();
        ArrayList<Character> origin_list = new ArrayList<>();
        for (int i = 0; i < origin_chars.length; i++) {
            origin_list.add(origin_chars[i]);
        }


        char[] encrypt_chars = encrypt.toCharArray();
        ArrayList<Character> encrypt_list = new ArrayList<>();

        for (int i = 0; i < encrypt_chars.length; i++) {
            encrypt_list.add(encrypt_chars[i]);
        }

        if(origin.trim().length() ==0 ||encrypt.trim().length() ==0 ) return;

        List<Integer> encrypt_result = Encrypt(origin_list);
        encrypt_result.forEach((i)-> System.out.print((char)((int)i)));

        System.out.println();

        List<Integer> decrypt_result = Decrypt(encrypt_list);
        decrypt_result.forEach((i)->System.out.print((char)((int)i)));


    }catch (IOException e){
        System.out.println(e.getMessage());
    }

}

public static  List<Integer> Encrypt(ArrayList<Character> input){

    List<Integer> collect = input.stream().map((i) -> {
        if (Character.isLetter(i)) {
            //大写
            if (i <= 90) {
                i = Character.toLowerCase(i);
            } else {
                i = Character.toUpperCase(i);
            }
            //Z -> a
            if (i == 122) return 97;
                //z -> A
            if (i==90) return 65;

            return i+1;
        } else {
            if (i < '9') return i + 1;
            else return i - 9;
        }
    }).collect(Collectors.toList());

    return collect;
}


public static  List<Integer> Decrypt(ArrayList<Character> input){

    List<Integer> collect = input.stream().map((i) -> {
        if (Character.isLetter(i)) {
            //a->Z
            if (i == 97) return 90;
            //A -> z
            if (i==65) return 122;

            i= (char)(i-1);
            //小写
            if (i>= 97 ) {
                i = Character.toUpperCase(i);
            } else {
                i = Character.toLowerCase(i);
            }


            return i+0;
        } else {
            if (i == '0' ) return i + 9;
            else return i-1;
        }
    }).collect(Collectors.toList());

    return collect;
}

}