033_Search_in_Rotated_Sorted_Array.py

# 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).
#
# You are given a target value to search. If found in the array return its index, otherwise return -1.
#
# You may assume no duplicate exists in the array.
#
# Tags: Binary Search, Array
# Difficulty: Hard


class Solution(object):
    def search(self, nums, target):
        """
        :type nums: List[int]
        :type target: int
        :rtype: int
        """
        left, right = 0, len(nums) - 1

        while left <= right:
            mid = (left + right) / 2

            if nums[mid] == target:
                return mid

            if nums[mid] >= nums[left]:
                if nums[left] <= target < nums[mid]:
                    right = mid - 1
                else:
                    left = mid + 1
            else:
                if nums[mid] < target <= nums[right]:
                    left = mid + 1
                else:
                    right = mid - 1

        return -1