二分法查找数据

        private static void QueryByMid()
        {
            int[] array = new int[] { 23, 33, 34, 43, 67, 78, 79 };
            int low = 0;
            int high = array.Length - 1;//这句很重要,减1避免数组值比较时索引超出
            int mid = 0;
            int queryNum = 78;//待查找的数
            int queryIndex = -1;

            while (low <= high)
            {
                mid = (low + high) / 2;
                if (queryNum == array[mid])
                {
                    queryIndex = mid;
                    break;
                }
                else
                {
                    if (queryNum < array[mid])
                    {
                        high = mid - 1;
                    }
                    else
                    {
                        low = mid + 1;
                    }
                }
            }
            if (queryIndex == -1)
            {
                Console.WriteLine("没有查找到对应的数据");
            }
            else
            {
                Console.WriteLine("数据查找到的索引位置：" + queryIndex);
            }
        }