Исправить код и вывод сортировки - C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
 
namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            int n = 10;
            int[] a = new int[n];
            Random rand = new Random();
            for (int i = 0; i < n; i++)
            {
                a[i] = rand.Next(100);
            }
            Console.ReadKey();
        }
        private static int[] QuickSort(int[] a, int i, int j)
        {
            if (i < j)
            {
                int q = Partition(a, i, j);
                a = QuickSort(a, i, q);
                a = QuickSort(a, q + 1, j);
            }
            return a;
        }
 
        private static int Partition(int[] a, int p, int r)
        {
            int x = a[p];
            int i = p - 1;
            int j = r + 1;
            while (true)
            {
                do
                {
                    j--;
                }
                while (a[j] > x);
                do
                {
                    i++;
                }
                while (a[i] < x);
                if (i < j)
                {
                    int tmp = a[i];
                    a[i] = a[j];
                    a[j] = tmp;
                }
                else
                {
                    return j;
                }
            }
        }
    }
}