Leetcode: 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.

Code (Java):

public class Solution {
    public int[] intersection(int[] nums1, int[] nums2) {
        if (nums1 == null || nums2 == null || nums1.length == 0 || nums2.length == 0) {
            return new int[0];
        }
        
        Arrays.sort(nums1);
        Arrays.sort(nums2);
        
        int i = 0;
        int j = 0;
        
        List<Integer> result = new ArrayList<>();
        while (i < nums1.length && j < nums2.length) {
            if (nums1[i] < nums2[j]) {
                i++;
            } else if (nums1[i] > nums2[j]) {
                j++;
            } else {
                if (result.isEmpty() || nums1[i] != result.get(result.size() - 1)) {
                    result.add(nums1[i]);
                }
                i++;
                j++;
            }
        }
        
        return listToArray(result);
    }
    
    private int[] listToArray(List<Integer> list) {
        int[] result = new int[list.size()];
        
        for (int i = 0; i < list.size(); i++) {
            result[i] = list.get(i);
        }
        
        return result;
    }
}