Given a sorted array of distinct integers nums and a target, return the index of target if it exists, otherwise -1. Your algorithm must run in O(log n) time.
Example 1
Input: nums = [-1,0,3,5,9,12], target = 9
Output: 4
Example 2
Input: nums = [-1,0,3,5,9,12], target = 2
Output: -1
Constraints
1 ≤ nums.length ≤ 10⁴
nums is sorted in ascending order with distinct values.