#include <iostream>
using namespace std;

class Slack {
    int size, quantity;
    bool if_exist;
    int* tab;
public:
    Slack(int x = 10) {
        cout << "To jest konstruktor!: "<<this << endl;
        init(x);
    }
    ~Slack() {
        cout << "To jest destruktor!: " <<this << endl;
        destroy();
    }
    void init(int x) {
        if_exist = true;
        tab = new int[x];
        size = x;
        quantity = -1;
    }
    void push(int x) {
        if (if_exist == false) { cout << "There is no slack!" << endl; return; }
        else if (quantity < size - 1) {
            quantity++;
            tab[quantity] = x;
            if_exist = true;
        }
        else cout << "There is no space!" << endl;
    }
    void pop() {
        if (if_exist == false) { cout << "There is no slack!" << endl; return; }
        else if (quantity < 0) cout << "There is nothing to pop!" << endl;
        else {
            tab[quantity] = 0;
            quantity--;
        }
    }
    int top() {
        if (if_exist == false) { cout << "There is no slack!" << endl; return -1; }
        else if (quantity < 0) { cout << "There is nothing to show!" << endl; return -1; }
        else {
            return tab[quantity];
        }
    }
    bool empty() {
        if (if_exist == false) { cout << "There is no slack!" << endl; return false; }
        if (quantity < 0) {cout << "It's empty, True!" << endl; return true;}
        else cout << "It's NOT empty, False!" << endl; return false;
    }
    bool full() {
        if (if_exist == false) {cout << "There is no slack!" << endl; return false;}
        if (quantity >= size - 1) {cout << "It is full, True!" << endl; return true;}
        else cout << "It is NOT full, False!" << endl; return false;
    }
    void destroy() {
        size = 0;
        quantity = 0;
        if_exist = false;
        delete[] tab;
    }
};
void f(Slack s, int a) {
    s.push(a);
}
int main() {
    Slack s;
    s.push(0);
    f(s, 1);
    f(s, 2);
    while (!s.empty()) {
        cout <<
            s.top();
        s.pop();
    }
}