How do I perform binary search in a rotated sorted array?

How do I perform binary search in a rotated sorted array?

To perform binary search in a rotated sorted array, you need to identify the pivot point where the array was rotated.

What if the array has duplicates?

If the array has duplicates, the algorithm may need to handle cases where the left and right elements are equal, which can complicate the search.

Can you provide a code example?

Sure! Here's a Python example:

def search(nums, target):
    left, right = 0, len(nums) - 1
    while left <= right:
        mid = (left + right) // 2
        if nums[mid] == target:
            return mid
        if nums[left] <= nums[mid]:
            if nums[left] <= target < nums[mid]:
                right = mid - 1
            else:
                left = mid + 1
        else:
            if nums[mid] < target <= nums[right]:
                left = mid + 1
            else:
                right = mid - 1
    return -1

This function returns the index of the target if found, otherwise -1.