public class Example6{
  public static void main(String args []){
      char a1 = '十',a2 = '点',a3 = '进' ,a4 = '攻';
      char secret = 'A';
      a1 = (char)(a1^secret); 
      a2 = (char)(a2^secret);
      a3 = (char)(a3^secret);
      a4 = (char)(a4^secret);
      System.out.println("密文:"+a1+a2+a3+a4);
      a1 = (char)(a1^secret);
      a2 = (char)(a2^secret);
      a3 = (char)(a3^secret);
      a4 = (char)(a4^secret);
      System.out.println("原文:"+a1+a2+a3+a4);
   }
}