Scanner scanner=new Scanner(System.in);
       String line = scanner.nextLine();
       while (!line.equals("end"))
       {
           int num1=line.charAt(0)-'0';
           int num2=line.charAt(2)-'0';
           char op = line.charAt(1);
           int result=0;
           if (op=='+')
               result=num1+num2;
           System.out.println(result);
           line = scanner.nextLine();
       }