Search in Rotated Sorted Array
Medium
Array
Binary Search
There is an integer array `nums` sorted in ascending order (with **distinct** values). Prior to being passed to your function, `nums` is **rotated** at an unknown pivot index `k`. Given the array `nums` *after* the 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
Time Complexity
O(log n)
Space Complexity
O(1)
14
Case 1
Input: [4,5,6,7,0,1,2] 0
Expected: 4
Case 2
Input: [4,5,6,7,0,1,2] 3
Expected: -1
Case 3
Input: [1] 0
Expected: -1