leetcode/Python/search-in-rotated-sorted-array.py at master · OnlyChristmas/leetcode · GitHub

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'''

Suppose an array sorted in ascending order 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.

Your algorithm's runtime complexity must be in the order of O(log n).

Example 1:

Input: nums = [4,5,6,7,0,1,2], target = 0
Output: 4
Example 2:

Input: nums = [4,5,6,7,0,1,2], target = 3
Output: -1


'''


class Solution:
    def search(self, nums: List[int], target: int) -> int:
        if len(nums) <= 0 : return -1
        l ,r = 0 , len(nums) - 1
        while l <= r :
            mid = l + (r - l) // 2
            if nums[mid] == target: return mid
            if nums[r] == target: return r
            if nums[l] < nums[mid]:
                if target >= nums[l] and nums[mid] >= target: r = mid - 1
                else: l = mid + 1
            else:
                if target >= nums[mid] and target <= nums[r]: l = mid + 1
                else: r = mid - 1
        return -1