Write a stack class that has an STL vector as a data member

Write a stack class that has an STL vector as a data member. Your class should implement push, peek, and pop.

Solution

template<class T>

class Stack {

public:

    Stack(const std::initializer_list<T>& i):elem(i) {}

    int size() const { return elem.size(); }

    bool empty() const { return elem.empty();}

    void push(const T&);

    T pop();

    T peek();

private:

    std::vector<T> elem;

};

template<class T>

void Stack<T>::push(const T& t) {

    elem.push_back(t);

}

template<class T>

T Stack<T>::pop() {

    if (empty()) {

        throw std::out_of_range(\"underflow\");

    }

    auto x = elem.back();

    elem.pop_back();

    return x;

}

template<class T>

T Stack<T>::peek() {

    if (empty()) {

        throw std::out_of_range(\"underflow\");

    }

    return elem.back();

}