using System;

​

namespace QuickSort

{

    public class Program

    {

        public static void Main()

        {

            //int[] array = new int[] { 5, 3, 1, 7, 4, 7 };

            int[] array = new int[]{3, 4, -1, 5, 215, -134, 5, 4, 5, 5, 5};

            //int[] array = new int[] { 5, 6, 1, 7, 4, 7, 3, 6, -1, -3 };

            QuickSort.Sort(array);

            Helpers.PrintArray(array);

        }

    }

}

​

namespace QuickSort

{

    public static class Helpers

    {

        public static void PrintArray(int[] array)

        {

            for (int index = 0; index < array.Length; index++)

            {

                Console.Write(array[index] + " ");

            }

        }

    }

}

​

namespace QuickSort

{

    public class QuickSort

    {

        private static void Sort(int[] array, int leftIndex, int rightIndex)

        {

            if (leftIndex < rightIndex)

            {

                int pivotIndex = (leftIndex + rightIndex) / 2;

                int pivotNumber = array[pivotIndex];

                int counterBiggerIndex = leftIndex;

                int counterLowerIndex = rightIndex;

                Partition(array, leftIndex, rightIndex, pivotNumber, counterBiggerIndex, counterLowerIndex);

                Sort(array, leftIndex, pivotIndex); //left part

                Sort(array, pivotIndex + 1, rightIndex); //right part

            }

        }

​

        private static void Partition(int[] array, int leftIndex, int rightIndex, int pivotNumber, int counterBiggerIndex, int counterLowerIndex)

        {

            while (counterLowerIndex > counterBiggerIndex)

            {

                while (counterBiggerIndex <= rightIndex)

                {

                    if (array[counterBiggerIndex] > pivotNumber)

                    {

                        break;

                    }

​

                    counterBiggerIndex++;

                }

​

                while (counterLowerIndex >= leftIndex)

                {

                    if (array[counterLowerIndex] <= pivotNumber)

                    {

                        break;

                    }

​

                    counterLowerIndex--;

                }

​

                if (counterLowerIndex > counterBiggerIndex)

                {

                    SwapElements(counterBiggerIndex, counterLowerIndex, array);

                }

            }

        }

​

        private static void SwapElements(int index1, int index2, int[] array)

        {

            int tempNumber = array[index1];

            array[index1] = array[index2];

            array[index2] = tempNumber;

        }

​

        public static void Sort(int[] array)

        {

            Sort(array, 0, array.Length - 1);

        }

    }

}