public static void Main()
{
// Create a new singly linked list of type string.
SinglyLinkedList <string> sll = new SinglyLinkedList <string>();
Console.WriteLine("Populate new singly linked list that is NOT a palindrome...");
sll.AddFirst("Dog");
sll.AddLast("Cat");
sll.AddLast("Pig");
sll.AddLast("Farm");
sll.Print();
// The IsPalindrome contains 3 methods:
// IsPalindrome: Call two helper methods: O(2n) (including helper method execution)
// ReverseAndCopy: O(n), with O(n) space.
// IsEqual: O(n)
// Runtime for IsPalindrome method: O(2n) -> O(n)
// with O(n) extra memory.
// Same can be done using a Stack...instead of copying a new linked list.
Console.WriteLine($"Is linked list a palindrome: {sll.IsPalindrome(sll.Head)}");
Console.WriteLine();
Console.WriteLine("Clear linked list.");
sll.Clear();
Console.WriteLine($"Linked list is Empty: {sll.IsEmpty()}");
Console.WriteLine();
Console.WriteLine("Populate new singly linked list that IS a palindrome...");
sll.AddFirst("Dog");
sll.AddLast("Cat");
sll.AddLast("Pig");
sll.AddLast("Cat");
sll.AddLast("Dog");
sll.Print();
Console.WriteLine($"Is linked list a palindrome: {sll.IsPalindrome(sll.Head)}");
}
