using System;

using System.Collections.Generic;

​

class Program

{

    static List<string> studentList = new List<string>();

​

    static void Main(string[] args)

    {

        while (true)

        {

            Console.WriteLine("Choose an operation:");

            Console.WriteLine("1. Add a new student");

            Console.WriteLine("2. Remove a student by index");

            Console.WriteLine("3. Remove students within a specified range");

            Console.WriteLine("4. Clear all students from the list");

            Console.WriteLine("5. Display all students");

            Console.WriteLine("6. Exit");

​

            int choice = int.Parse(Console.ReadLine());

​

            switch (choice)

            {

                case 1:

                    AddStudent();

                    break;

                case 2:

                    RemoveStudentByIndex();

                    break;

                case 3:

                    RemoveStudentsInRange();

                    break;

                case 4:

                    ClearStudents();

                    break;

                case 5:

                    DisplayStudents();

                    break;

                case 6:

                    Console.WriteLine("Exiting the program...");

                    return;

                default:

                    Console.WriteLine("Invalid choice. Please try again.");

                    break;

            }

        }

    }

​

    static void AddStudent()

    {

        Console.WriteLine("Enter the name of the student:");

        string studentName = Console.ReadLine();

        studentList.Add(studentName);

        Console.WriteLine("Student added successfully!");

    }

​

    static void RemoveStudentByIndex()

    {

        Console.WriteLine("Enter the index of the student to remove:");

        int index = int.Parse(Console.ReadLine());

​

        if (index >= 0 && index < studentList.Count)

        {

            studentList.RemoveAt(index);

            Console.WriteLine("Student removed successfully!");

        }

        else

        {

            Console.WriteLine("Invalid index. No student removed.");

        }

    }

​

    static void RemoveStudentsInRange()

    {

        Console.WriteLine("Enter the starting index of the range:");

        int startIndex = int.Parse(Console.ReadLine());

​

        Console.WriteLine("Enter the ending index of the range:");

        int endIndex = int.Parse(Console.ReadLine());

​

        if (startIndex >= 0 && startIndex < studentList.Count && endIndex >= startIndex && endIndex < studentList.Count)

        {

            studentList.RemoveRange(startIndex, endIndex - startIndex + 1);

            Console.WriteLine("Students removed successfully!");

        }

        else

        {

            Console.WriteLine("Invalid range. No students removed.");

        }

    }

​

    static void ClearStudents()

    {

        studentList.Clear();

        Console.WriteLine("All students removed from the list.");

    }

​

    static void DisplayStudents()

    {

        if (studentList.Count == 0)

        {

            Console.WriteLine("No students in the list.");

        }

        else

        {

            Console.WriteLine("List of students:");

            for (int i = 0; i < studentList.Count; i++)

            {

                Console.WriteLine($"{i}. {studentList[i]}");

            }

        }

    }

}