#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;
}