#include <iostream>
#include <cstdlib>
#include <iterator>
#include <vector>
using namespace std;

template <class ITERATOR>
void f(ITERATOR first, ITERATOR last)
{
	typename iterator_traits<ITERATOR>::value_type x = *first;
	cout << x << " is a copy of the value to which first refers.\n";

	typename iterator_traits<ITERATOR>::pointer p = &*first;
	cout << "first refers to the value " << *p << " at address "
		<< static_cast<const void *>(p) << ".\n";

	typename iterator_traits<ITERATOR>::reference r = *first;
	cout << "first refers to the value " << r << " at address "
		<< static_cast<const void *>(&r) << ".\n";

	typename iterator_traits<ITERATOR>::difference_type d = 0;
	for (; first != last; ++first) {
		++d;
	}

	cout << "The iterators refer to elements that are " << d
		<< " elements apart.\n\n";
}

int main()
{
	int a[] = {10, 20, 30, 40, 50};
	const size_t n = sizeof a / sizeof a[0];
	cout << fixed;

	int *it1 = a;
	int *it2 = a + n - 1;
	f(it1, it2);

	vector<double> v(a, a + n);
	vector<double>::iterator it3 = v.begin();
	f(it3, it3 + 3);

	return EXIT_SUCCESS;
}