Leetcode 81: Search in Rotated Sorted Array II

Follow up for "Search in Rotated Sorted Array":
What if duplicates are allowed?

Would this affect the run-time complexity? How and why?

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).

Write a function to determine if a given target is in the array.

The array may contain duplicates.

 

public class Solution {
    public bool Search(int[] nums, int target) {
        return BinarySearch(nums, target, 0, nums.Length - 1);
    }
    
    private bool BinarySearch(int[] nums, int target, int start, int end)
    {
        if (start > end) return false;
        
        if (start == end) return nums[start] == target;
        
        if (nums[start] == target || nums[end] == target) return true;
        
        int mid = start + (end - start) / 2;
        
        if (nums[mid] == target) return true;
        
        if (nums[start] < nums[mid])
        {
            if (target > nums[start] && target < nums[mid])
            {
                return BinarySearch(nums, target, start + 1, mid - 1);
            }
            else
            {
                return BinarySearch(nums, target, mid + 1, end - 1);
            }
        }
        else if (nums[start] == nums[mid])
        {
            return BinarySearch(nums, target, start + 1, mid - 1) || BinarySearch(nums, target, mid + 1, end - 1);
        }
        else if (nums[end] == nums[mid])
        {
            return BinarySearch(nums, target, start + 1, mid - 1) || BinarySearch(nums, target, mid + 1, end - 1);
        }
        else
        {
            if (target > nums[mid] && target < nums[end])
            {
                return BinarySearch(nums, target, mid + 1, end - 1);
            }
            else
            {
                return BinarySearch(nums, target, start + 1, mid - 1);
            }
        }
        
        return false;
    }
}