using System;

unsafe class Program
{
    //struct Header
    //{
    //    internal int* data;
    //};

    //Header* object_header = stackalloc Header[sizeof(Header)];
    //object_header->data = stackalloc int[length];

    static void SwapMe(int* first, int* second)
    {
        int tmp = *first;
        *first = *second;
        *second = tmp;
    }

    static void SortQuick(int* data, int low, int high)
    {
        int i = low,
            j = high,
            x = data[(low + high) / 2];

        do
        {
            while (data[i] < x) i++;
            while (data[j] > x) j--;

            if (i <= j)
            {
                SwapMe(&data[i], &data[j]);
                i++;
                j--;
            }

        } while (i <= j);

        if (low < j) SortQuick(data, low, j);
        if (j < high) SortQuick(data, j, high);
    }

    static void ArrayPrint(int* data, int length)
    {
        for (int i = 0; i < length; i++)
        {
            Console.WriteLine(data[i]);
        }
    }

    static void Main()
    {
        int length = new Random().Next(1000, 99999);
        int* data = stackalloc int[length];
        int capicity = length * sizeof(int);

        for (int i = 0; i < capicity; i++)
        {
            data[i] = new Random().Next(0, 9999);
        }

        ArrayPrint(data, capicity);
        SortQuick(data, 0, length - 1);
        ArrayPrint(data, capicity);

        Console.ReadLine();
    }
}