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.

Solution:

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