Search in Rotated Sorted Array

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**). 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.