/**************************************************************************
 *
 * memfunc.cpp - Example program for mem_fun and other member function
 *               pointer wrappers.  See Class Reference Section.
 *
 ***************************************************************************
 *
 * Copyright (c) 1994-1999 Rogue Wave Software, Inc.  All Rights Reserved.
 *
 * This computer software is owned by Rogue Wave Software, Inc. and is
 * protected by U.S. copyright laws and other laws and by international
 * treaties.  This computer software is furnished by Rogue Wave Software,
 * Inc. pursuant to a written license agreement and may be used, copied,
 * transmitted, and stored only in accordance with the terms of such
 * license and with the inclusion of the above copyright notice.  This
 * computer software or any other copies thereof may not be provided or
 * otherwise made available to any other person.
 *
 * U.S. Government Restricted Rights.  This computer software is provided
 * with Restricted Rights.  Use, duplication, or disclosure by the
 * Government is subject to restrictions as set forth in subparagraph (c)
 * (1) (ii) of The Rights in Technical Data and Computer Software clause
 * at DFARS 252.227-7013 or subparagraphs (c) (1) and (2) of the
 * Commercial Computer Software – Restricted Rights at 48 CFR 52.227-19,
 * as applicable.  Manufacturer is Rogue Wave Software, Inc., 5500
 * Flatiron Parkway, Boulder, Colorado 80301 USA.
 *
 **************************************************************************/

#include <vector>
#include <functional>
#include <algorithm>

#ifdef _RW_STD_IOSTREAM
#include <iostream>
#else
#include <iostream.h>
#endif     

#ifndef _RWSTD_NO_NAMESPACE
using namespace std;
#endif        

//
// Very large city class
//
class MegaPolis
{
public:

  MegaPolis(char*  s = 0 , float n = 0):cityName(s),population(n) {;}
  // The following function cannot return void due to limitations in 
  // some current C++ implementations. 
  virtual size_t byPopulation()
  {
    cout<<cityName<<"(MegaPolis)"<<"\t\t\t"<<population<<endl;
    return 0;
  }
  float population;
protected:
  char* cityName;
};

//
// City and surrounding area class
//
class MetroPolis : public MegaPolis
{
public:
  MetroPolis(char*  s = 0 , float n = 0):MegaPolis(s,n){;}
  virtual size_t byPopulation()
  {
    cout<<cityName<<"(MetroPolis)"<<"\t\t\t"<<population<<endl;
    return 0;
  }
};

//
// Functor compares the size of two MeagPolis classes
//
struct GreaterPopulation
{
  bool operator()(MegaPolis* m1, MegaPolis* m2)
  {
    return m1->population<m2->population;
  }
} greater_pop;


int main()
{
  // 
  // Create a vector of very lareg cities
  //
  vector<MegaPolis*, allocator<MegaPolis*> > cityList;

  cityList.push_back(new  MegaPolis ("Calcutta",35));
  cityList.push_back(new  MegaPolis ("Tokyo",20));
  cityList.push_back(new  MegaPolis ("Delhi",10)); 
  cityList.push_back(new  MegaPolis ("Bombay",15));
  
  cityList.push_back(new  MetroPolis ("Cairo",5));
  cityList.push_back(new  MetroPolis ("New York",2.5));
  cityList.push_back(new  MetroPolis ("Los Angeles",3)); 
  cityList.push_back(new  MetroPolis ("Jakarta",1.5));
  
   // 
   // Now use mem_fun to pass byPopulation member function
   // of MegaPolis to the for_each function.
   //
  cout<<"City                    "<<" Population (in millions)    "<<endl;
  cout<<"-----                   "<<" -----------------------"<<endl;  
  for_each(cityList.begin(),cityList.end(),mem_fun(&MegaPolis::byPopulation));
  cout<<"..............After sorting..........................."<<endl;
  stable_sort(cityList.begin(),cityList.end(),greater_pop);
  for_each(cityList.begin(),cityList.end(),mem_fun(&MegaPolis::byPopulation));

  return 0;
}