#include <iostream>
#include <vector>

using namespace std;

struct Node {
    Node(Node *n, int v) : next_(n), value(v){}

    Node *next_;
    int value;
};

struct Stack {
    Node *head = nullptr;

    void push(int value) {
        head = new Node(head, value);
    }

    void pop() {
        auto tmp = head;
        head = head->next_;
        delete tmp;
    }

    void print() {
        auto curr = head;
        while (curr) {
            cout << curr->value << ' ';
            curr = curr->next_;
        }
    }
    ~Stack(){
      while(head){
          pop();
      }
    }
};