Sorting for LinkedList

MergeSort_LinkedList.cs

using System;

namespace MergeSort_LinkedList
{
    internal class ListNode
    {
        public int Val { get; set; }
        public ListNode Next { get; set; }

        public ListNode(int val = 0, ListNode next = null)
        {
            Val = val;
            Next = next;
        }
    }

    internal static class Program
    {
        private static void Main()
        {
            var random = new Random();
            ListNode head = null;

            for (var i = 0; i <= 10; i++)
                head = new ListNode(random.Next(0, 100), head);

            PrintNodes(head);
            Console.WriteLine();
            Console.WriteLine(new string('-', 30));
            head = MergeSort(head);
            PrintNodes(head);
        }

        private static ListNode MergeSort(ListNode head)
        {
            if (head?.Next is null) return head;

            var arr = SplitNode(head);
            var left = arr[0];
            var right = arr[1];

            left = MergeSort(left);
            right = MergeSort(right);

            return Merge(left, right);
        }

        private static ListNode Merge(ListNode left, ListNode right)
        {
            if (left is null) return right;
            if (right is null) return left;

            ListNode mergedList;

            if (left.Val > right.Val)
            {
                mergedList = right;
                mergedList.Next = Merge(left, right.Next);
            }
            else
            {
                mergedList = left;
                mergedList.Next = Merge(left.Next, right);
            }

            return mergedList;
        }

        private static ListNode[] SplitNode(ListNode head)
        {
            if (head?.Next == null) return new[] {head, null};
            var left = head;
            var right = head.Next;

            while (right != null)
            {
                right = right.Next;
                if (right != null)
                {
                    left = left.Next;
                    right = left.Next;
                }
            }

            ListNode[] arr = {head, left.Next};
            left.Next = null;

            return arr;
        }

        private static void PrintNodes(ListNode head)
        {
            while (head != null)
            {
                Console.Write($"{head.Val} ");
                head = head.Next;
            }
        }
    }
}