do { // Do While Loop that incorporates Menu and List Functions
	system("cls"); //clears previous entries & redisplays the Menu per selection
	 // Displays Menu Screen for user interaction of List
	cout << "**********Menu*************"<< endl; 
	cout << "*   1. Populate List      *"<< endl;
	cout << "*   2. Sort list          *"<< endl;
	cout << "*   3. Search List        *"<< endl;
	cout << "*   4. Display List       *"<< endl;
	cout << "*   0. Exit               *"<< endl; 
	cout << "***************************"<< endl;
	cout << "                           "<< endl;
	cout << "Please select your option  "<< endl;
        cin >> n;
	cout << "                           "<< endl;
 
		switch (n)
		{
		case 1 :
			disp.populate(); 
			cout << "List populated."<< endl;
			system("Pause");
		break;
		case 2 :
			disp.sort(); 
			system("Pause");
		break;
		case 3 :
			cout << "Please enter the value you wish to search from the List"<< endl;
			cin  >> p;
			system("Pause"); 
		break;
		case 4 :
			disp.toString(); 
			system("Pause");
		break;
		default:
			if (n !=0) 
			{
			cout << "Enter a number relating to the Options shown!!!" << endl;
			system("Pause");
			}
		break;
		} 
	}
	while (n != 0); // Exit Condition
	system("Pause");

do {
  display_menu();
  select_option();
while (!done);

do {
  display_menu();
  do {
    select_option();
  while (invalid_option);
while (!done)

case 0:
 
return 0;
 
break;