public static void SelectionMethod()
        {
            Console.WriteLine("Please select");
            Console.WriteLine("Data Structure: \n 1 : Big O(n) \n 2 : Array \n 3 : Linked List \n 4 : Stack \n 7 : Factorial recursion \n 8 : Fibonacci \n 9 : ReverseString (Recursion) \n 10 : Bubble Sort \n 11 : Selection Sort \n 12 : Insertion Sort");
            Console.Write("Please enter your selection: ");
            string str = Console.ReadLine();

            switch (str)
            {
            case "1":
                BigOn.Call100();
                break;

            case "2":
                DSArray.ChooseArray();
                break;

            case "3":
                LinkedList linkedList = new LinkedList(5);
                linkedList.LinkListOperation();
                break;

            case "4":
                Stack stack = new Stack();
                stack.StackOperation();
                break;

            case "7":
                Factorial fact = new Factorial();
                fact.FindFactorial();
                break;

            case "8":
                Fibonacci fibonacci = new Fibonacci();
                fibonacci.FindFibonacci();
                break;

            case "9":
                ReverseString rev = new ReverseString();
                rev.RevString();
                break;

            case "10":
                BubbleSort bubble = new();
                bubble.BubbleSorting();
                break;

            case "11":
                SelectionSort selection = new();
                selection.SortSelection();
                break;

            case "12":
                InsertionSort insertion = new();
                insertion.Insertion();
                break;
            }
        }