using System;

//Professor Class

public class Professor

{

    // [Code] Define Fields

    public string ProfessorName;

    private int _Age;

    private string _Degree;

    // [Code] Define Property Age

    // Make sure Age is between 18 and 70

    // If Age violates the rule, set the default value as 30

    public int Age

    {

        get

        {

            return _Age;

        }

        set

        {

            if (value >18 && value <70)

            {

                _Age = value;

            }

            else {

                _Age = 30;

            }

        }

    }

    // [Code] Define Property Degree

    // The degree's value should only equal to "master" or "phd".

    public string Degree

    {

        get

        {

            return _Degree;

        }

        set

        {

            if (value == "Master" | value == "PhD")

            {

                _Degree = value;

            }

            else {

                _Degree = "Master";

            }

        }

    }

    // [Code] Constructor

    public Professor()

    {

    }

}

​

//Course Class

public class Course

{

    // [Code] Define Fields

    public string CourseName;

    public string CourseID;

    public int ClassLimit;

    // [Code] Properties CourseID

    // Make sure CourseID has exactly 4 characters

    public string CourseLength

    {

        get

        {

            return CourseID;

        }

        set

        {

            if (CourseID.Length == 4)

            {

                CourseLength = CourseID;

            }

            else

            {

                CourseLength = "Invalid Course!";

            }

        }

    }

    // Make sure ClassLimit is under 50

    public int LowerLimit

    {

        get

        {

            return ClassLimit;

        }

        set

        {

            if (value < 1)

            {

                LowerLimit = 1;

            }

            else

            {

                LowerLimit = ClassLimit;

            }

        }

    }

    public int UpperLimit

    {

        get

        {

            return ClassLimit;

        }

        set

        {

            if (value > 50)

            {

                UpperLimit = 50;

            }

            else

            {

                UpperLimit = ClassLimit;

            }

        }

    }

    // [Code] Constructor

    public Course()  {

    }

}

​

public class Program

{

    public static void Main()

    {

        //[Code] Create an object ProfessorTuna

        // ProfessorName: Tuna

        // Age: 99

        Professor ProfessorTuna = new Professor();

        ProfessorTuna.ProfessorName = "Tuna";

        ProfessorTuna.Age = 99;

        //[Code] Create an object CourseS308

        // CourseID: S308

        // CourseName: C#

        // ClassCapacity: 21

        Course CourseS308 = new Course();

        CourseS308.CourseID = "S308";

        CourseS308.CourseName = "C#";

        CourseS308.ClassLimit = 21;

        // [Code] Show professor's age and course capacity

        // What happens if the age is greater than 70?

        Console.WriteLine("Professor {0} is {1} years old", ProfessorTuna.ProfessorName, ProfessorTuna.Age);

        //The age is set to 30 since it is not within the bounds of 18 and 70 as the program defines

        Console.WriteLine("Course {0} has a class limit of {1}", CourseS308.CourseID,CourseS308.ClassLimit);

    }

}