LeetCode 350. Intersection of Two Arrays II

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

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

Note:

• Each element in the result should appear as many times as it shows in both arrays.
• The result can be in any order.

class Solution {
public:
    vector<int> intersect(vector<int>& nums1, vector<int>& nums2) {
        if(nums1.size() == 0 || nums2.size() == 0) return {};
        sort(nums1.begin(), nums1.end());
        sort(nums2.begin(), nums2.end());
        
        int i = 0, j = 0;
        vector<int> res;
        while(i < nums1.size() && j < nums2.size()) {
            if(nums1[i] == nums2[j]) {
                res.push_back(nums1[i]);
                i++;
                j++;
            } else if(nums1[i] < nums2[j]) {
                i++;
            } else j++;
        }
        return res;
    }
};