gistfile1.cs

//QuickSort in C# with random pivot
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace QuickSort
{
    class Program
    {
        //common Swap function
        static void Swap<T>(ref T lhs, ref T rhs)
        {
            T temp;
            temp = lhs;
            lhs = rhs;
            rhs = temp;
        }

        //qiucksort procedure
        static void qsort(int[] tab, int left, int right)
        {
            if (left < right)
            {

                System.Random myRandom = new System.Random(); //Creating instance of random variable

                int m = myRandom.Next(left, right); //pivot = random number between left a right
               Swap(ref tab[left],ref tab[m]);

                for (int i = left + 1; i <= right; i++)
                    if (tab[i] < tab[left])
                        Swap(ref tab[++m], ref tab[i]);

                Swap(ref tab[left], ref tab[m]);

                qsort(tab, left, m - 1);
                qsort(tab, m + 1, right);
            }


        }






        static void Main(string[] args)
        {
            Console.Title = "QuickSort";
            int[] a = { 0, 12, 34, 9, 54, 12, 77, -3};
            int i;
            int left = 0;
            int right = 7;


            Console.WriteLine("Data before sort ");
            for (i = 0; i < a.Length; i++)
                Console.Write(" {0} ", a[i]);
            Console.WriteLine();
            //call quicksort procedure
            qsort(a, left, right);

            Console.WriteLine("Data after sort");
            for (i = 0; i < a.Length; i++)
                Console.Write(" {0} ", a[i]);
            Console.WriteLine();
            Console.ReadLine();



        }
    }
}