#include <bits/stdc++.h>
#include <iostream>
using namespace std;


// harmadik feladat
vector<int> common(vector<int> a, vector<int> b) {
    vector<int> out;
    for (int i = 0; i < a.size(); i++) {
        for (int j = 0; j < b.size(); j++) {
            if (a[i] == b[j]) {
                out.push_back(a[i]);
            }
        }
    }
    return out;
}

int main() {
    vector<int> a = {1,2,3,4,5,6};
    vector<int> b = {2,4,6,8,10};
    vector<int> out = common(a,b);

    for (int i = 0; i < out.size(); i++) {
        cout<<out[i]<<" ";
    }
}