Solution2.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
 

namespace cSharpSolutions
{
    internal class Solution2
    {
        // Node class
        private class Node
        {
            public int Value;
            public Node Next;

            public Node(int value)
            {
                Value = value;
                Next = null;
            }
        }

        // LinkedList class
        private class SinglyLinkedList
        {
            private Node head;

            // Add at end
            public void Append(int value)
            {
                var newNode = new Node(value);
                if (head == null)
                {
                    head = newNode;
                    return;
                }

                Node current = head;
                while (current.Next != null)
                    current = current.Next;

                current.Next = newNode;
            }

            // Add at beginning
            public void Prepend(int value)
            {
                var newNode = new Node(value)
                {
                    Next = head
                };
                head = newNode;
            }

            // Delete first occurrence
            public bool Delete(int value)
            {
                if (head == null) return false;

                if (head.Value == value)
                {
                    head = head.Next;
                    return true;
                }

                Node current = head;
                while (current.Next != null && current.Next.Value != value)
                    current = current.Next;

                if (current.Next == null) return false;

                current.Next = current.Next.Next;
                return true;
            }

            // Search for value
            public bool Contains(int value)
            {
                Node current = head;
                while (current != null)
                {
                    if (current.Value == value)
                        return true;
                    current = current.Next;
                }
                return false;
            }

            // Reverse in-place
            public void Reverse()
            {
                Node prev = null;
                Node current = head;
                Node next = null;

                while (current != null)
                {
                    next = current.Next;
                    current.Next = prev;
                    prev = current;
                    current = next;
                }

                head = prev;
            }

            // Print list
            public void Print()
            {
                Node current = head;
                Console.Write("List: ");
                while (current != null)
                {
                    Console.Write(current.Value + " -> ");
                    current = current.Next;
                }
                Console.WriteLine("null");
            }
        }

        // Run method
        public static void Run()
        {
            Console.WriteLine("=== Solution 2: Singly Linked List ===");

            var list = new SinglyLinkedList();

            Console.WriteLine("Appending 1, 2, 3, 4, 5, 6, 7, 8, 9");
            list.Append(1);
            list.Append(2);
            list.Append(3);
            list.Append(4);
            list.Append(5);
            list.Append(6);
            list.Append(7);
            list.Append(8);
            list.Append(9);
            list.Print();

            Console.WriteLine("Prepending 0");
            list.Prepend(0);
            list.Print();

            Console.WriteLine("Deleting 2:");
            list.Delete(2);
            list.Print();

            Console.WriteLine("Deleting 5:");
            list.Delete(5);
            list.Print();

            Console.WriteLine("Deleting 9:");
            list.Delete(9);
            list.Print();

            Console.WriteLine("Reversing list:");
            list.Reverse();
            list.Print();

            Console.WriteLine($"Contains 0? {list.Contains(0)}");
            Console.WriteLine($"Contains 2? {list.Contains(2)}");

            Console.WriteLine("\nSolution 2 complete");
        }
    }
}