#include <iostream>
#include <vector>
#include <stack>

using namespace std;


int main ()
{
    vector<int> numbers{4, 15, 8, 7, 9, 31};
    stack <int> s;

    for (auto i : numbers){
        s.push(i);
    }


    cout << "\ns.size() : " << s.size();
    cout << "\ns.top() : " << s.top();


    cout << "\ns.pop() : ";
    cout << &s.top();


    return 0;
}