#ifndef NODEH
#define NODEH
#include <iterator>   //for iterator_traits and forward_iterator_tag
using namespace std;

struct node {
	int value;
	node *next;

	node(int initial_value, node *initial_next)
		: value(initial_value), next(initial_next) {}

	class iterator {
		node *p;
	public:
		iterator(node *initial_p = 0): p(initial_p) {}
		int& operator*() const {return p->value;}
		iterator& operator++() {p = p->next; return *this;}   //prefix

		friend bool operator==(const iterator& it1, const iterator& it2) {
			return it1.p == it2.p;
		}
	};
};

inline const node::iterator operator++(node::iterator& it, int)	//postfix
{
	const node::iterator old = it;
	++it;   //it.operator++();
	return old;
}

inline bool operator!=(const node::iterator& it1, const node::iterator& it2)
{
	return !(it1 == it2);   //return !operator==(it1, it2);
}

namespace std {
	template <>
	struct iterator_traits<node::iterator> {
		typedef forward_iterator_tag iterator_category;
		typedef int value_type;
		typedef ptrdiff_t difference_type;
		typedef int *pointer;
		typedef int& reference;
	};                      //semicolon at end of class
}                           //no semicolon at end of namespace
#endif