> ## Documentation Index
> Fetch the complete documentation index at: https://leetcode-py.wisl.dev/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> leetcode-py is a Python LeetCode practice environment generator with one CLI: lcpy. It is not a service or platform.
> Each problem is a directory under leetcode/ with README.md, solution.py, test_solution.py, helpers.py, and playground.ipynb. lcpy gen creates them from JSON templates bundled with the package.
> Examples are backed by tests; copy them verbatim.

# Search in Rotated Sorted Array II

> Tested Python solution for LeetCode 81 with 18 pytest cases. Generate a practice environment with lcpy.

LeetCode 81, Medium. Topics: Array, Binary Search. [View on LeetCode](https://leetcode.com/problems/search-in-rotated-sorted-array-ii/description/).

Generate this problem as a practice environment: tested reference solution, 18 [parametrized pytest cases](/practice/testing), and a playground notebook:

```bash theme={"theme":{"light":"github-light","dark":"github-dark"}}
lcpy gen -n 81   # by problem number
lcpy gen -s search_in_rotated_sorted_array_ii   # by problem name
```

## Problem

There is an integer array `nums` sorted in non-decreasing order (not necessarily with **distinct** values).

Before being passed to your function, `nums` is **rotated** at an unknown pivot index `k` (`0 <= 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, `[0,1,2,4,4,4,5,6,6,7]` might be rotated at pivot index `5` and become `[4,5,6,6,7,0,1,2,4,4]`.

Given the array `nums` **after** the rotation and an integer `target`, return `true` *if* `target` *is in* `nums`*, or* `false` *if it is not in* `nums`*.*

You must decrease the overall operation steps as much as possible.

### Examples

```
Input: nums = [2,5,6,0,0,1,2], target = 0
Output: true
```

```
Input: nums = [2,5,6,0,0,1,2], target = 3
Output: false
```

### Constraints

* 1 \<= nums.length \<= 5000
* -10^4 \<= nums\[i] \<= 10^4
* `nums` is guaranteed to be rotated at some pivot.
* -10^4 \<= target \<= 10^4

**Follow up:** This problem is similar to [Search in Rotated Sorted Array](https://leetcode.com/problems/search-in-rotated-sorted-array/description/), but `nums` may contain **duplicates**. Would this affect the runtime complexity? How and why?

## Solution

Reference implementation from [solution.py on GitHub](https://github.com/wislertt/leetcode-py/blob/main/leetcode/search_in_rotated_sorted_array_ii/solution.py), full suite in [test\_solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/search_in_rotated_sorted_array_ii/test_solution.py):

```python theme={"theme":{"light":"github-light","dark":"github-dark"}}
class Solution:
    # Time: O(n) worst case (duplicates collapse bounds), O(log n) average
    # Space: O(1)
    def search(self, nums: list[int], target: int) -> bool:
        left = 0
        right = len(nums) - 1

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

            if nums[mid] == target:
                return True

            # Ambiguous boundary: shrink from both ends when all three equal
            if nums[left] == nums[mid] == nums[right]:
                left += 1
                right -= 1
            elif nums[left] <= nums[mid]:  # left half sorted
                if nums[left] <= target < nums[mid]:
                    right = mid - 1
                else:
                    left = mid + 1
            else:  # right half sorted
                if nums[mid] < target <= nums[right]:
                    left = mid + 1
                else:
                    right = mid - 1

        return False
```

## Complexity

| Time                                                           | Space |
| -------------------------------------------------------------- | ----- |
| O(n) worst case (duplicates collapse bounds), O(log n) average | O(1)  |

## Tags

[NeetCode 250](/catalog/neetcode-250), [NeetCode All](/catalog/neetcode).