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SaiPavan Seelamsetty
SaiPavan Seelamsetty

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Search in Rotated Sorted Array - Python

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]. 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.

https://leetcode.com/problems/search-in-rotated-sorted-array/

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

class Solution:
    def search(self, nums: List[int], target: int) -> int:
        #TC=O(log n)
        s=0
        e=len(nums)-1
        while s<=e:
            mid=(s+e)//2
            if nums[mid]==target:
                return mid
           #left-line
            if nums[s]<=nums[mid]:
                if target>=nums[s] and target<=nums[mid]:
                    e=mid-1
                else:
                    s=mid+1
            else:
                if target>=nums[mid] and target<=nums[e]:
                    s=mid+1
                else:
                    e=mid-1
        return -1     
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