Intersection of Two Arrays

Given two integer arrays first and second, return an array of their intersection. Each element in the result must be unique, and the result must be sorted in ascending order.

Example 1:

Input: first = [1,2,2,1], second = [2,2]
Output: [2]

Example 2:

Input: first = [4,9,5], second = [9,4,9,8,4]
Output: [4,9]
Explanation: 4 and 9 are in both arrays. Each appears twice in second, but only once in the result.

Constraints:

• 1 <= first.length, second.length <= 1000
• -1000 <= first[i], second[i] <= 1000