62. 搜索旋转排序数组

class Solution:
    """
    @param A: an integer rotated sorted array
    @param target: an integer to be searched
    @return: an integer
    """
    def search(self, A, target):
        # write your code here
        if not A: return -1
        
        start, end = 0, len(A) - 1 
        
        while start + 1 < end:
            mid = (start + end) // 2 
            
            if (A[mid] == target):
                return mid
                
            #如果左边是升序的，在左边进行判断
            if (A[start] < A[mid]):
                #如果在start和mid区间的话，如果start和mid中间是升序的，否则则else
                if (A[start] <= target) and (target <= A[mid]):
                    end = mid
                else:
                    start = mid
            
            #如果左边存在降序，则在右边判断，mid不停的切分区间
            else:
                #如果在mid和end区间,如果mid和end之间是升序的
                if (A[mid] <= target) and (target <= A[end]):
                    start = mid
                else:
                    end = mid
            
        #如果均不符合，则外面判断
        if (A[start] == target):
            return start
        elif (A[end] == target):
            return end
        return -1

result = Solution().search([5,6,0,1,2,3,4],4)
print(result)