Find Minimum in Rotated Sorted Array

Description:

Suppose a sorted array is rotated at some pivot unknown to you beforehand.

(i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2).

Find the minimum element.

You may assume no duplicate exists in the array.

Code:

int findMinElement(vector<int>& nums, int indexLeft, int indexRight)

    {

        if (indexLeft < indexRight)

        {

            if ( nums[(indexLeft+indexRight)/2] < nums[indexRight])

                return findMinElement(nums, indexLeft, (indexLeft+indexRight)/2);//注意：(indexLeft+indexRight)/2可能就是最小值

            else

                 return findMinElement(nums, (indexLeft+indexRight)/2+1, indexRight);

        }

        else

            return nums[indexLeft];

    }

    int findMin(vector<int>& nums) {

        return findMinElement(nums, 0, nums.size()-1 );

    }