You are given an integer array, nums, that is sorted in non-decreasing order. Your task is to find the first and last indexes of a given value, target, within this array.

If the target does not appear in the array at all, return [-1, -1].

Note: You must write an algorithm with $O(\log n)$ runtime complexity.

Constraints:

• $0 \le$ nums.length $\leq 10^5$ ...