/* -*- C++ -*-
 * src/lemon/extended_pair.h - Part of LEMON, a generic C++ optimization library
 *
 * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
 * (Egervary Combinatorial Optimization Research Group, EGRES).
 *
 * Permission to use, modify and distribute this software is granted
 * provided that this copyright notice appears in all copies. For
 * precise terms see the accompanying LICENSE file.
 *
 * This software is provided "AS IS" with no warranty of any kind,
 * express or implied, and with no claim as to its suitability for any
 * purpose.
 *
 */

#ifndef LEMON_EXTENDED_PAIR_H
#define LEMON_EXTENDED_PAIR_H

template <typename T1, typename A1, typename T2, typename A2>
struct extended_pair {
  typedef T1 first_type;
  typedef T2 second_type;

  extended_pair() : first(), second() {}

  extended_pair(A1 f, A2 s) : first(f), second(s) {}

  template <class Pair>
  extended_pair(const Pair& pair) : first(pair.first), second(pair.second) {}

  T1 first;
  T2 second;
};

template <typename T1, typename T2, 
	  typename LA1, typename LA2, typename RA1, typename RA2>
bool operator==(const extended_pair<T1, LA1, T2, LA2>& left, 
		const extended_pair<T1, RA1, T2, RA2>& right) {
  return left.first == right.first && left.second == right.second;
}

template <typename T1, typename T2, 
	  typename LA1, typename LA2, typename RA1, typename RA2>
bool operator!=(const extended_pair<T1, LA1, T2, LA2>& left, 
		const extended_pair<T1, RA1, T2, RA2>& right) {
  return  !(left == right);
}

template <typename T1, typename T2, 
	  typename LA1, typename LA2, typename RA1, typename RA2>
bool operator<(const extended_pair<T1, LA1, T2, LA2>& left, 
		const extended_pair<T1, RA1, T2, RA2>& right) {
  return left.first < right.first || 
           (!(right.first<left.first) && left.second < right.second);
}

template <typename T1, typename T2, 
	  typename LA1, typename LA2, typename RA1, typename RA2>
bool operator>(const extended_pair<T1, LA1, T2, LA2>& left, 
		const extended_pair<T1, RA1, T2, RA2>& right) {
  return right < left;
}

template <typename T1, typename T2, 
	  typename LA1, typename LA2, typename RA1, typename RA2>
bool operator<=(const extended_pair<T1, LA1, T2, LA2>& left, 
		const extended_pair<T1, RA1, T2, RA2>& right) {
  return !(right > left);
}

template <typename T1, typename T2, 
	  typename LA1, typename LA2, typename RA1, typename RA2>
bool operator>=(const extended_pair<T1, LA1, T2, LA2>& left, 
		const extended_pair<T1, RA1, T2, RA2>& right) {
  return !(right < left);
}


#endif