33\. Search in Rotated Sorted Array

Medium

There is an integer array `nums` sorted in ascending order (with **distinct** values).

Prior to being passed to your function, `nums` is **possibly rotated** at an unknown pivot index `k` (`1 <= k < nums.length`) such that the resulting array is `[nums[k], nums[k+1], ..., nums[n-1], nums[0], nums[1], ..., nums[k-1]]` (**0-indexed**). For example, `[0,1,2,4,5,6,7]` might be rotated at pivot index `3` and become `[4,5,6,7,0,1,2]`.

Given the array `nums` **after** the possible rotation and an integer `target`, return _the index of_ `target` _if it is in_ `nums`_, or_ `-1` _if it is not in_ `nums`.

You must write an algorithm with `O(log n)` runtime complexity.

**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 

**Example 3:**

**Input:** nums = [1], target = 0

**Output:** -1 

**Constraints:**

*   `1 <= nums.length <= 5000`
*   <code>-10<sup>4</sup> <= nums[i] <= 10<sup>4</sup></code>
*   All values of `nums` are **unique**.
*   `nums` is an ascending array that is possibly rotated.
*   <code>-10<sup>4</sup> <= target <= 10<sup>4</sup></code>