Create an Employee class that includes three private data members— firstName (type
string), lastName (type string), and monthlySalary (type int ).
It also includes several public member functions.
1. A constructor initializes the three data members.
2. A setFirstName function accepts a string parameter and does not return any data. It
sets the firstName.
3. A getFirstName function does not accept any parameter and returns a string. It returns
the firstName.
4. A setLastName function accepts a string parameter and does not return any data. It sets
the lastName.
5. A getLastName function does not accept any parameter and returns a string. It returns
the lastName.
6. A setMonthlySalary function accepts an integer parameter and does not return any
data. It sets the monthlySalary. If the monthly salary is less than or equal zero, set it to
1000 and it displays the employee’s first name, last name and the inputted salary with a
statement “**==The salary is set to $1000.”
7. A getMonthlySalary function does not accept any parameter and returns an integer. It
returns the monthlySalary. 

8. An increaseMonthlySalary function accepts an integer parameter and does not return
any data. It increases the monthlySalary by integer%. The increase could be positive or
negative. When this function is called the salary adjusted employee’s name and salary
information will be displayed (please see the following image for details).