Find first and last index of target

You are given an integer array `nums` sorted in non-decreasing order and an integer `target`. Return a pair `[left, right]` where: - `left` is the index of the first occurrence of `target` in `nums` - `right` is the index of the last occurrence of `target` in `nums` If `target` does not exist in the array, return `[-1, -1]`. ## Requirements - Your algorithm must run in **O(log n)** time. ## Input/Output - **Input:** `nums: int[]`, `target: int` - **Output:** `int[2]` representing `[left, right]` ## Constraints - `0 <= nums.length <= 1e5` - `-1e9 <= nums[i], target <= 1e9` - `nums` is sorted in non-decreasing order. ## Examples - `nums = [5,7,7,8,8,10]`, `target = 8` → `[3,4]` - `nums = [5,7,7,8,8,10]`, `target = 6` → `[-1,-1]` - `nums = []`, `target = 0` → `[-1,-1]`