算法之禅-二分查找

public int Search(int[] nums, int target) {

        int left = 0;

        int right = nums.Length - 1;

        while(left <= right)

        {

            int middle = left + (right - left)/2;

            if (nums[middle]>target)

            {

                right = middle - 1;

            }else if (nums[middle]<target)

            {

                left = middle + 1;

            }else

            {

                return middle;

            }

        }

        // 未找到目标值

        return -1;

    }

 

//注意中间值：left+(right-left)/2 = mid;