What is problem in my submission

#1

please explain the algorithm in my code

#2

your Mistakes:

  1. you are not taking next operator(i.e. ch) each time

    cin>>ch;

  2. you are not calculating output for ‘%’ operator;

  3. other operators such as special cases(i.e. $, #,;,…) you have to providing output as: "Invalid operation. Try again."

  4. whenever you receive the operator ‘x’ or ‘X’ your calculator stop execution.

Modified Code :

i hope this help, if you have further doubt then feel free to ask;