#ifndef STACK_H_INCLUDED
#define STACK_H_INCLUDED

#include <vector>
using namespace std;

template<typename T>
class Stack;

template<typename T>
Stack<T> operator+(const Stack<T>& a, const Stack<T>& b);

template<typename T>
class Stack
{
    private:
    friend Stack<T> operator+<>(const Stack<T>& a, const Stack<T>& b);

    vector<T> data;

    public:
    void printAll() { for(int a=0;a<data.size();a++) cout << data[a] << endl; cout << endl;}
    Stack() {}
    bool isEmpty() const { return data.empty(); }
    void push(const T& item) { data.push_back(item); }
    const T& top() const { return data.back(); }
    T& top() { return data.back(); }
    void pop() { data.pop_back(); }
};

template<typename T>
Stack<T> operator+(const Stack<T>& a, const Stack<T>& b)
{
    Stack<T> c = a;
    for(int k=0;k<b.data.size();k++)
        c.push(b.data[k]);

    return c;
}


#endif // STACK_H_INCLUDED