# 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`
* `-104 <= nums[i] <= 104`
* All values of `nums` are **unique**.
* `nums` is an ascending array that is possibly rotated.
* `-104 <= target <= 104`

```python
class Solution:
    def search(self, nums: List[int], target: int) -> int:
        pivot = self.findPivot(nums, target)
        return pivot
    
    def findPivot(self, nums, target):
        low = 0
        high = len(nums)-1
        while low <= high:
            mid = low+(high-low)//2
            if nums[mid] == target:
                return mid
            elif nums[low] <= nums[mid]:
                if nums[low] <= target <= nums[mid]:
                    high = mid - 1
                else:
                    low = mid + 1
            else:
                if nums[mid] <= target <= nums[high]:
                    low = mid + 1
                else:
                    high = mid - 1
        return -1
```