Find the Power of K-Size Subarrays I

Description

You are given an array of integers nums of length n and a positive integer k.

The power of an array is defined as:

- Its maximum element if all of its elements are consecutive and sorted in ascending order.

- -1 otherwise.

You need to find the power of all subarrays of nums of size k.

Return an integer array results of size n - k + 1, where results[i] is the power of nums[i..(i + k - 1)].