private static void MergeConsole(string location, int[] arr)
        {
            Console.Write($"{location}: ");
            foreach (var i in arr)
            {
                Console.Write("{0}\t", i);
            }
            Console.WriteLine();
        }
        /// <summary>
        /// 归并数组
        /// </summary>
        /// <param name="arr">要归并的数组</param>
        /// <param name="left">归并左序列首元素下标</param>
        /// <param name="mid">拆分元素的下标</param>
        /// <param name="right">归并右序列最后元素下标</param>
        private static void MergeArray(int[] arr, int left, int mid, int right)
        {
            int[] temp = new int[right - left + 1];
            int m = left, n = mid + 1, k = 0;
            while (n <= right && m <= mid)
            {
                if (arr[m] > arr[n])
                {
                    temp[k++] = arr[n++];
                }
                else
                {
                    temp[k++] = arr[m++];
                }
            }
            while (n < right + 1)
            {
                temp[k++] = arr[n++];
            }
            while (m < mid + 1)
            {
                temp[k++] = arr[m++];
            }
            for (k = 0, m = left; m < right + 1; k++, m++)
            {
                arr[m] = temp[k];
            }
        }
        /// <summary>
        /// 归并排序
        /// </summary>
        /// <param name="arr">要归并的数组</param>
        /// <param name="left">归并左序列首元素下标</param>
        /// <param name="right">归并右序列最后元素下标</param>
        public static void MergeSort(int[] arr, int left, int right)
        {
            if (left < right)
            {
                int mid = (left + right) / 2;
                MergeSort(arr, left, mid);
                MergeConsole("_left: ", arr);
                MergeSort(arr, mid + 1, right);
                MergeConsole("right: ", arr);
                MergeArray(arr, left, mid, right);
                MergeConsole("merge: ", arr);
                Console.WriteLine();
            }
        }

        static void Main(string[] args)
        {
            int[] array = { 149, 100, 112, 38, 80, 35, 615, 297, 592, 976, 143, 217 };
            MergeSort(array, 0, array.Length - 1);
            Console.ReadLine();
        }