349. 两个数组的交集
class Solution {
public:
vector<int> intersection(vector<int>& nums1, vector<int>& nums2) {
unordered_set<int> ans_set;
unordered_set<int> num1_set(nums1.begin(), nums1.end());
for(int elem : nums2){
if(num1_set.find(elem) != num1_set.end()){
ans_set.insert(elem);
}
}
return vector<int>(ans_set.begin(), ans_set.end());
}
};