349. Intersection of Two Arrays

Given two arrays, write a function to compute their intersection.

Example:
Given nums1 = [1, 2, 2, 1], nums2 = [2, 2], return [2].

Note:
Each element in the result must be unique.
The result can be in any order.

public class Solution {
    public int[] intersection(int[] nums1, int[] nums2) {
        Arrays.sort(nums1);
        Arrays.sort(nums2);
        HashSet<Integer> set = new HashSet<Integer>();
        int l1 = 0, l2 = 0;
        while(l1 < nums1.length && l2 < nums2.length) {
           if(nums1[l1] < nums2[l2]) {
               l1++;
           }else if(nums1[l1] > nums2[l2]) {
               l2++;
           } else {
               if(!set.contains(nums1[l1])){
                   set.add(nums1[l1]);
               }
               l1++;
               l2++;
           }
        }
        int[] res = new int[set.size()];
        int i = 0;
        for(Integer x : set) {
            res[i++] = x;
        }
        return res;
    }
}