template <class t>
class Stack
{
private:
    t * arr;
    int top;
    int siz;
    void Reserve()
    {
        t *temp = arr;
        int sz=siz;
        arr = new t[siz*2];
        siz*=2;
        top=-1;
        for(int i=0; i<sz; i++)
            push(temp[i]);
    }
public:
    Stack()
    {
        siz=10;
        arr = new t[siz];
        top=-1;
    }
    Stack(Stack &s)
    {
        siz=s.siz;
        arr = new int[s.siz];
        for(int i=0; i<siz; i++)
            arr[i] = s.arr[i];
        top=s.top;
        siz=s.siz;
    }
    ~Stack()
    {
        delete arr;
    }
    void push(t x)
    {
        if(isFull())
            Reserve();
        top++;
        arr[top]=x;
    }
    void pop(t &x)
    {
        if(isEmpty())
        {
            cout<<"Stack is already empty"<<endl;
            throw;
        }
        x=arr[top];
        top--;
    }
    t pop()
    {
        if(isEmpty())
        {
            cout<<"Stack is already empty"<<endl;
            throw;
        }
        int temp=top;
        top--;
        return arr[temp];
    }
    bool isFull()
    {
        if(top==siz-1) return 1;
        return 0;
    }
    bool isEmpty()
    {
        if(top==-1) return 1;
        return 0;
    }
    void peek()
    {
       cout<<"top "<<arr[top]<<endl;
    }
};