#ifndef STACK_H
#define STACK_H
#include <cstddef>   //for size_t
using namespace std;

class stack {
	static const size_t max_size {100};
	int a[max_size];
	size_t n;        //stack pointer: subscript of next free element
public:
	stack(): n {0} {}  //A stack is born empty.
	virtual ~stack() {}

	virtual void push(int i) {a[n++] = i;}
	virtual int pop() {return a[--n];}

	size_t size() const {return n;}
	static size_t capacity() {return max_size;}
};
#endif