You are required to write a program which will calculate the salary of an employee according to his/her grade assigned by the employer. You must declare a class named CalSalary whose private data members will be employee ID, employee name and employee grade. Also write a constructor, setter and getter functions for all private data members and a function that will calculate the salary.

Detailed Description:

• Employee ID and grade should be of type integer. Employee name should be of type string.
• Constructor should initialize employee ID and grade with value zero and employee name with value NULL.
• For assigning or extracting values from private data members, you must use getter and setter functions.
• Declare a public member function named calculate which will calculate the net salary of the employee according to his/her grade.
• Formula for calculating actual salary is (Basic Salary) + 45% of basic salary.
• If the grade of employee is 17, then the basic salary is 15,000.
• If the grade is 18, then the basic salary is 20,000 and if grade is 19 then the basic salary is 25,000.