二分法基础

class Program
    {
        static void Main(string[] args)
        {
            int[] array = new int[6] { 1,2,3,4,5,6};


            Console.WriteLine(Search(array, 6));
        }


        static int Search(int[] array, int num)
        {
            int low = 0;
            int high = array.Length;


            while (low <= high)
            {
                int middle = (low + high) / 2;


                if (array[middle] == num)
                {
                    return middle;
                }
                else if (array[middle] < num)
                {
                    low = middle + 1;
                }
                else
                {
                    high = middle - 1;
                }
            }


            return -1;
        }
    }