using System;

class Course

    {

        string c_name;

        int units;

        float mark;

​

        public Course()

        {

            mark = 0;

        }

        public void CourseInputData()

        {

            Console.Write("\nEnter Course name:");

            c_name = Console.ReadLine();

​

            Console.Write("Enter number of Units:");

            units = Convert.ToInt16(Console.ReadLine());

​

            Console.Write("Enter Mark:");

            mark = Convert.ToSingle(Console.ReadLine());

        }

        public float GetMark()

        {

            return (mark);

        }

        public int GetUnit()

        {

            return (units);

        }

        public void ShowInfo()

        {

            Console.WriteLine("\n{0}  {1} =====> {2}", c_name,units,mark);

        }}

 class student

        {

        string fname;

        string lname;

        string StID;

        double Average;

        int N_Course;  //Number of Courses

        Course[] st_Courses = new Course[20];

        public student()

        {}

​

        public void InputData()

        {

            Console.Write("\n\nEnter First name:");

            fname = Console.ReadLine();

​

            Console.Write("Enter Last name:");

            lname = Console.ReadLine();

​

            Console.Write("Enter Student ID:");

            StID = Console.ReadLine();

​

            Console.Write("Enter number of Courses:");

            N_Course = Convert.ToInt16(Console.ReadLine());

​

            for (int j = 0; j < N_Course; j++)

            {

                Console.Write("***Enter Course Information:");

                st_Courses[j] = new Course();

                st_Courses[j].CourseInputData();

            }

        }

​

        public void calcAvg()

        {

            double sum = 0;  

            int TotalUnits = 0;

            for (int i = 0; i < N_Course; i++)

            {

                sum = sum + st_Courses[i].GetMark() * st_Courses[i].GetUnit();

                TotalUnits = TotalUnits + st_Courses[i].GetUnit();

            }

            Average = sum / TotalUnits; 

        }

​

​

        public void ShowInfo()

        {

            Console.WriteLine("\n{0}  {1} =====> {2}", fname, lname, Average);

​

        }

​

​

        public static void Sortlist(student[] y, int n)

        {

            student temp = new student();

            for (int i = 0; i < n; i++)

                for (int j = 0; j < n - i - 1; j++)

                    if (y[j].Average > y[j + 1].Average)

                    {

                        temp = y[j];

                        y[j] = y[j + 1];

                        y[j + 1] = temp;

                    }

        }

      public static void FindBests(student[] a, int n)

        {

            Console.WriteLine("\n\n The Best Student in List with Average Greater Than 17:");

            for (int i = 0; i < n; i++)

                if (a[i].Average >= 17)

                    a[i].ShowInfo();

                }

        public static void FindBeststudent(student[] a, int n)

        {

            student temp =new student();

            temp =  a[0];

            for (int i = 0; i < n; i++)

                if (a[i].Average > temp.Average)

                temp= a[i];

            temp.ShowInfo();

                }

    } //End Of Student Class

public class Program

{

    public static void Main()

    {

     Console.Write("Enter number of Students:");

            int N_ST = Convert.ToInt16(Console.ReadLine());

​

            student[] st = new student[N_ST];

​

            for (int i = 0; i < N_ST; i++)

            { 

                st[i] = new student();

                st[i].InputData();

                st[i].calcAvg();

            }

​

            student.FindBests(st, N_ST);

​

            Console.WriteLine("\n\n Sorted List:");

            student.Sortlist(st, N_ST);

​

            for (int i = 0; i < N_ST; i++)

                st[i].ShowInfo();

         Console.WriteLine("\n\n_____________________");

         Console.WriteLine("\n\n The best student:");

        student.FindBeststudent(st,N_ST);

            Console.ReadKey();

    }

}