#include <iostream>
#include <vector>
using namespace std;


int main() {
    
    vector<int> v;
    
    v.push_back(1);
    v.emplace_back(2);
    v.push_back(3);
    
    for(int i = 0; i < (int) v.size(); i++) {
        cout << v[i] << " ";
    }
    cout << endl;
    
    for(int x: v) {
        cout << x << " ";
    }
    cout << endl;
    
    return 0;
}