Find the Most Competitive Subsequence

Given an integer array `nums` and a positive integer `k`, return _the most** competitive** subsequence of _`nums` _of size _`k`. An array's subsequence is a resulting sequence obtained by erasing some (possibly zero) elements from the array. We define that a subsequence `a` is more **competitive** than a subsequence `b` (of the same length) if in the first position where `a` and `b` differ, subsequence `a` has a number **less** than the corresponding number in `b`. For example, `[1,3,4]` is more competitive than `[1,3,5]` because the first position they differ is at the final number, and `4` is less than `5`.   **Example 1:** **Input:** nums = [3,5,2,6], k = 2 **Output:** [2,6] **Explanation:** Among the set of every possible subsequence: {[3,5], [3,2], [3,6], [5,2], [5,6], [2,6]}, [2,6] is the most competitive. ``` **Example 2:** **Input:** nums = [2,4,3,3,5,4,9,6], k = 4 **Output:** [2,3,3,4] ```   **Constraints:** - `1 <= nums.length <= 105` - `0 <= nums[i] <= 109` - `1 <= k <= nums.length`