题解 | #字符串加密#

import java.util.; import java.io.;

public class Main{ //字符串加密 public static void main(String[] args) {

    final InputStreamReader reader = new InputStreamReader(System.in);
    try(  BufferedReader br = new BufferedReader(reader)){

         char[] chars = br.readLine().toCharArray();
         char[] password = br.readLine().toCharArray();


            StringBuffer sb = new StringBuffer();
         StringBuffer sb_result = new StringBuffer();

         String dic = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        LinkedHashSet<Character> set = new LinkedHashSet<>();
        LinkedHashSet<Character> set_dic = new LinkedHashSet<>();

        char[] chars_dic = dic.toCharArray();
        for (char c : chars_dic) {
            set_dic.add(c);
        }

        for (int i = 0; i < chars.length; i++) {
            if (!set.contains(chars[i])){
                sb.append(chars[i]);
                set.add(chars[i]);
                set_dic.remove(Character.toUpperCase(chars[i]));
            }
        }

        //生成组合密文
        set_dic.forEach(e->sb.append(e));

        for (int i = 0; i < password.length; i++) {
            //获取字符在原字典中的索引
             int index = dic.indexOf(Character.toUpperCase(password[i]));
              String now_str = sb.toString().substring(index, index + 1);
             if (password[i] <=90) {
                sb_result.append(now_str.toUpperCase());
             }
             else sb_result.append(now_str.toLowerCase());
        }
        
        System.out.println(sb_result);


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

}

}