正三角，倒三角，正金字塔，倒金字塔，快排

 class Program
    {
        static void Main(string[] args)
        {

            int length = 10;
            Console.WriteLine("倒三角：");
            for (int i = 0; i < length; i++)
            {
                for (int j = length; i < j; j--)
                {
                    Console.Write("*");
                }
                Console.WriteLine();
            }

          

            System.Threading.Thread.Sleep(2000);
            Console.WriteLine("倒金字塔：");
            for (int i = length; i >= 0 ; i--)
            {
                for (int m = length - i; m > 0; m--)
                {
                    Console.Write(" ");
                }


                for (int j = 0; j < (i * 2 )+1; j++)
                {
                                      
                    Console.Write("*");
                }
                Console.WriteLine();
            }


            System.Threading.Thread.Sleep(2000);
            Console.WriteLine("正三角：");
            for (int i = 0; i < length; i++)
            {
                for (int j = 0; j < i; j++)
                {
                    Console.Write("*");
                }
                Console.WriteLine();
            }
            System.Threading.Thread.Sleep(2000);

            Console.WriteLine("金字塔：");
            for (int i = 0; i < length; i++)
            {
                for (int m = length - i; m > 0; m--)
                {
                    Console.Write(" ");
                }



                for (int j = 0; j < ( i * 2 ) + 1; j++)
                {    
                    Console.Write("*");
                }
                Console.WriteLine();
            }
            System.Threading.Thread.Sleep(2000);
            Console.WriteLine("金字塔△：");
            for (int i = 0; i < length; i++)
            {
                for (int m = length - i; m > 0; m--)
                {
                    Console.Write(" ");
                }



                for (int j = 0; j < i; j++)
                {
                    Console.Write("△");
                }
                Console.WriteLine();
            }
            System.Threading.Thread.Sleep(2000);
            Console.WriteLine("金字塔-：");
            for (int i = 0; i < length; i++)
            {
                for (int m = length - i; m > 0; m--)
                {
                    Console.Write(" ");
                }



                for (int j = 0; j < (i * 2) + 1; j++)
                {
                    Console.Write("-");
                }
                Console.WriteLine();
            }
            System.Threading.Thread.Sleep(2000);
            Console.WriteLine("排序前：");


            int[] arr = { 5, 66, 24, 22, 19, 11, 18, 21, 56, 77, 12, 66, 45 };

            for (int i = 0; i < arr.Length; i++)
            {
                Console.WriteLine(arr[i]);
            }

            quick_sort(ref arr, 0, arr.Length-1);

            System.Threading.Thread.Sleep(2000);

            Console.WriteLine("排序后：");
            for (int i = 0; i < arr.Length; i++)
            {
                Console.WriteLine(arr[i]);
            }

            //降序
            Array.Reverse(arr);
            foreach (var b in arr)
            {
                Console.Write(b + " ");
            }

        }

        public static void quick_sort(ref int[] s, int start, int end)
        {
            if (start < end)
            {
               
                int i = start, j = end, x = s[start];
                while (i < j)
                {
                    // 从右向左找第一个小于x的数
                    while (i < j && s[j] >= x) 
                        j--;
                    if (i < j)
                        s[i++] = s[j];
                    // 从左向右找第一个大于等于x的数
                    while (i < j && s[i] < x) 
                        i++;
                    if (i < j)
                        s[j--] = s[i];
                }
                s[i] = x;
                // 递归调用 
                quick_sort(ref s, start, i - 1); 
                quick_sort(ref s, i + 1, end);
            }
        }

    }
}