static void Main()
        {
            ArrayList aspirantlist = new ArrayList();
            ArrayList studentlist  = new ArrayList();
            bool      check        = true;

            do
            {
                Console.Write("If you wanna register as student press - 1 :\nIf you wanna register as aspirant press - 2 : ");
                int press12 = TryPress12();
                switch (press12)
                {
                case 1:
                {
                    Console.Write("\nInput name of student : "); string  name     = Alphabet_chechker();
                    Console.Write("Input surname of student : "); string surname  = Alphabet_chechker();
                    Console.Write("Input course of student : "); int     course   = TryPress();
                    Console.Write("Input codebook of student : "); int   codebook = TryPress();
                    Student student = new Student(name, surname, course, codebook);
                    studentlist.Add(student);
                    break;
                }

                case 2:
                {
                    Console.Write("\nInput name of aspirant : "); string      name        = Alphabet_chechker();
                    Console.Write("Input surname of aspirant : "); string     surname     = Alphabet_chechker();
                    Console.Write("Input course of aspirant : "); int         course      = TryPress();
                    Console.Write("Input codebook of aspirant : "); int       codebook    = TryPress();
                    Console.Write("Input disertation of aspirant : "); string disertation = Console.ReadLine();
                    Aspirant aspirant = new Aspirant(name, surname, course, codebook, disertation);
                    aspirantlist.Add(aspirant);
                    break;
                }
                }
                Console.Write("\nFor continue press - 1 :\nFor see all users registered list and exit press - 2 : ");
                int menu = TryPress12();
                switch (menu)
                {
                case 1:
                {
                    check = true;
                    break;
                }

                case 2:
                {
                    check = false;
                    break;
                }
                }
            } while (check == true);



            foreach (Aspirant each in aspirantlist)
            {
                Console.WriteLine("\nYour aspirant : ");
                Console.ForegroundColor = ConsoleColor.Green;
                Console.Write("Name of aspirant - " + each.name + ",surname - " + each.surname + ",course - " + each.course + ",codebook - " + each.codebook + ",disertation - " + each.disertation);
                Console.ResetColor();
            }

            foreach (Student each in studentlist)
            {
                Console.WriteLine("\nYour student : ");
                Console.ForegroundColor = ConsoleColor.Yellow;
                Console.Write("Name of student - " + each.name + ",surname - " + each.surname + ",course - " + each.course + ",codebook - " + each.codebook);
                Console.ResetColor();
            }
            Console.Read();
        }
        static void Main()
        {
            bool check = true;

            do
            {
                LinkedList <Student>  studentlinked  = new LinkedList <Student>();
                LinkedList <Aspirant> aspirantlinked = new LinkedList <Aspirant>();
                Console.Write("If you wanna register as student press - 1 :\nIf you wanna register as aspirant press - 2 : ");
                int press12 = TryPress12();
                switch (press12)
                {
                case 1:
                {
                    Console.Write("Input name of student : "); string    name     = Alphabet();
                    Console.Write("Input surname of student : "); string surname  = Alphabet();
                    Console.Write("Input course of student : "); int     course   = TryPress();
                    Console.Write("Input codebook of student : "); int   codebook = TryPress();
                    Student student = new Student(name, surname, course, codebook);
                    studentlinked.AddFirst(student);
                    break;
                }

                case 2:
                {
                    Console.Write("Input name of aspirant : "); string        name        = Alphabet();
                    Console.Write("Input surname of aspirant : "); string     surname     = Alphabet();
                    Console.Write("Input course of aspirant : "); int         course      = TryPress();
                    Console.Write("Input codebook of aspirant : "); int       codebook    = TryPress();
                    Console.Write("Input disertation of aspirant : "); string disertation = Console.ReadLine();
                    Aspirant aspirant = new Aspirant(name, surname, course, codebook, disertation);
                    aspirantlinked.AddFirst(aspirant);
                    break;
                }
                }
                Console.Write("\nFor continue press - 1 \nFor see all users registered list and exit press - 2 : ");
                int menu = TryPress12();
                switch (menu)
                {
                case 1:
                {
                    break;
                }

                case 2:
                {
                    check = false;
                    break;
                }
                }
                foreach (Student st in studentlinked)
                {
                    Console.ForegroundColor = ConsoleColor.Green;
                    Console.WriteLine("\nName of aspirant - " + st.name + ",surname - " + st.surname + ",course - " + st.course +
                                      ",codebook - " + st.name);
                }
                foreach (Aspirant asp in aspirantlinked)
                {
                    Console.ForegroundColor = ConsoleColor.Yellow;
                    Console.WriteLine("\nName of aspirant - " + asp.name + ",surname - " + asp.surname + ",course - " + asp.course +
                                      ",codebook - " + asp.name + ",disertation - " + asp.disertation);
                }
            } while (check == true);
            Console.ResetColor();
            Console.Read();
        }
        static void Main()
        {
            bool checki = true;

            do
            {
                Console.Write("If you wanna register as student press - 1 :\nIf you wanna register as aspirant press - 2 : ");
                int press12 = TryPress12();
                switch (press12)
                {
                case 1:
                {
                    Console.Write("Input name of student : "); string    name     = Alphabet();
                    Console.Write("Input surname of student : "); string surname  = Alphabet();
                    Console.Write("Input course of student : "); int     course   = TryPress();
                    Console.Write("Input codebook of student : "); int   codebook = TryPress();
                    Student student = new Student(name, surname, course, codebook);
                    studentlist.Add(student);
                    break;
                }

                case 2:
                {
                    Console.Write("Input name of aspirant : "); string        name        = Alphabet();
                    Console.Write("Input surname of aspirant : "); string     surname     = Alphabet();
                    Console.Write("Input course of aspirant : "); int         course      = TryPress();
                    Console.Write("Input codebook of aspirant : "); int       codebook    = TryPress();
                    Console.Write("Input disertation of aspirant : "); string disertation = Console.ReadLine();
                    Aspirant aspirant = new Aspirant(name, surname, course, codebook, disertation);
                    aspirantlist.Add(aspirant);
                    break;
                }
                }
                Console.Write("\nFor continue  press - 1: \nFor see  users registered list press - 2 : ");
                int menu = TryPress12();
                switch (menu)
                {
                case 1:
                {
                    checki = true;
                    break;
                }

                case 2:
                {
                    checki = false;
                    break;
                }
                }
            } while (checki == true);


            bool check = true;

            do
            {
                Console.WriteLine("\nFor get student with index press 1:\nFor get aspirant with index press 2:\nFor exit and get full list press 3:");
                int presskey = TryPress();
                switch (presskey)
                {
                case 1:
                {
                    bool checkcase = true;
                    do
                    {
                        Console.Write(" Input index of student : ");
                        int index = TryPress12();
                        if (index >= studentlist.Count)
                        {
                            Console.WriteLine("\nEmpty list,try again!"); checkcase = true;
                        }
                        else
                        {
                            Student stud = (Student)studentlist[index];
                            Console.WriteLine("Student name - {0} , surname - {1} , course - {2} , codebook - {3}", stud.name, stud.surname, stud.course, stud.codebook);
                            Console.Write("For continue checking press - 1 , for go to menu - 2 : ");
                            int num = TryPress12();
                            if (num == 1)
                            {
                                checkcase = true;
                            }
                            else
                            {
                                checkcase = false;
                            }
                        }
                    } while (checkcase == true);
                    break;
                }

                case 2:
                {
                    bool checkcase = true;
                    do
                    {
                        Console.Write("Input index of student : ");
                        int index = TryPress();
                        if (index >= aspirantlist.Count)
                        {
                            Console.WriteLine("\nEmpty list,try again!"); checkcase = false;
                        }
                        else
                        {
                            Console.ForegroundColor = ConsoleColor.Green;
                            Aspirant asp = (Aspirant)aspirantlist[index];
                            Console.WriteLine("Student name - {0} , surname - {1} , course - {2} , codebook - {3}", asp.name, asp.surname, asp.course, asp.codebook);
                            Console.ResetColor();
                            Console.Write("For continue checking press - 1 , for go to menu - 2 : ");
                            int num = TryPress12();
                            if (num == 1)
                            {
                                checkcase = true;
                            }
                            else
                            {
                                checkcase = false;
                            }
                        }
                    } while (checkcase == true);
                    break;
                }

                case 3:
                {
                    check = false;
                    break;
                }
                }
            } while (check == true);

            foreach (Aspirant each in aspirantlist)
            {
                Console.Write("\n Your aspirant : ");
                Console.ForegroundColor = ConsoleColor.Yellow;
                Console.Write("Name of aspirant - " + each.name + ",surname - " + each.surname + ",course - " + each.course + ",codebook - " + each.codebook + ",disertation - " + each.disertation);
                Console.ResetColor();
            }

            foreach (Student each in studentlist)
            {
                Console.Write("\n Your student : ");
                Console.ForegroundColor = ConsoleColor.Green;
                Console.Write("Name of student - " + each.name + ",surname - " + each.surname + ",course - " + each.course + ",codebook - " + each.codebook);
                Console.ResetColor();
            }
            Console.Read();
        }