LeetCode-Problems/Easy Problems/349_Intersection_of_Two_Arrays.cpp at main · UdaySharmaGitHub/LeetCode-Problems · GitHub

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/*
Given two integer arrays nums1 and nums2, return an array of their intersection. Each element in the result must be unique and you may return the result in any order.


Example 1:

Input: nums1 = [1,2,2,1], nums2 = [2,2]
Output: [2]
Example 2:

Input: nums1 = [4,9,5], nums2 = [9,4,9,8,4]
Output: [9,4]
Explanation: [4,9] is also accepted.


Constraints:

1 <= nums1.length, nums2.length <= 1000
0 <= nums1[i], nums2[i] <= 1000
*/
// Brute Force O(nlog(n)) complexity
class Solution {
public:
    vector<int> intersection(vector<int>& nums1, vector<int>& nums2) {
        sort(nums1.begin(),nums1.end());
        sort(nums2.begin(),nums2.end());
        vector<int> ans;
        int i =0 , j =0;
        int last  = -1;
        while(i<nums1.size() && j< nums2.size()){
            if(nums1[i]==nums2[j]){
                if(last!=nums1[i]){
                     ans.push_back(nums1[i]);
                 last = nums1[i];
                }
                 i++;j++;
            }
            else if(nums1[i]>nums2[j]){
                  j++;
            }
            else{
                i++;
            }
        }
        return ans;
    }
};