Subversion Repositories openrisc_2011-10-31

// -*- C++ -*-

// Copyright (C) 2005, 2006, 2009 Free Software Foundation, Inc.

//

// This file is part of the GNU ISO C++ Library.  This library is free

// software; you can redistribute it and/or modify it under the terms

// of the GNU General Public License as published by the Free Software

// Foundation; either version 3, or (at your option) any later

// version.

// This library is distributed in the hope that it will be useful, but

// WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

// General Public License for more details.

// You should have received a copy of the GNU General Public License

// along with this library; see the file COPYING3.  If not see

// <http://www.gnu.org/licenses/>.

// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.

// Permission to use, copy, modify, sell, and distribute this software

// is hereby granted without fee, provided that the above copyright

// notice appears in all copies, and that both that copyright notice

// and this permission notice appear in supporting documentation. None

// of the above authors, nor IBM Haifa Research Laboratories, make any

// representation about the suitability of this software for any

// purpose. It is provided "as is" without express or implied

// warranty.

/**

 * @file priority_queue_container_traits_example.cpp

 * A basic example showing how to use container_traits for querying container types

 *    for their behavior.

 */

/**

 * The following example shows how to use container_traits in order to print

 * out information on an priority queue's behavior, e.g., its underlying

 * data structure.

 */

#include <iostream>

#include <ext/pb_ds/priority_queue.hpp>

#include <ext/pb_ds/tag_and_trait.hpp>

using namespace std;

using namespace __gnu_pbds;

template<class DS_Category>

void

print_container_category(DS_Category);

template<>

void

print_container_category(binary_heap_tag)

{ cout << "Binary heap:" << endl; }

template<>

void

print_container_category(binomial_heap_tag)

{ cout << "Binomial heap:" << endl; }

template<>

void

print_container_category(rc_binomial_heap_tag)

{ cout << "Redundant-counter binomial heap:" << endl; }

template<>

void

print_container_category(pairing_heap_tag)

{ cout << "Pairing heap:" << endl; }

template<>

void

print_container_category(thin_heap_tag)

{ cout << "Thin heap:" << endl; }

template<class Invalidation_Guarantee>

void

print_invalidation_guarantee(Invalidation_Guarantee);

template<>

void

print_invalidation_guarantee(basic_invalidation_guarantee)

{

  cout << "Guarantees only that found references, pointers, and "

    "iterators are valid as long as the container object is not "

    "modified" << endl;

}

template<>

void

print_invalidation_guarantee(point_invalidation_guarantee)

{

  cout << "Guarantees that found references, pointers, and "

    "point_iterators are valid even if the container object "

    "is modified" << endl;

}

template<>

void

print_invalidation_guarantee(range_invalidation_guarantee)

{

  cout << "Guarantees that iterators remain valid even if the "

    "container object is modified" << endl;

}

void

print_split_join_can_throw(bool can)

{

  if (can)

    {

      cout << "Can throw exceptions if split or joined" << endl;

      return;

    }

  cout << "Cannot throw exceptions if split or joined" << endl;

}

template<class DS_Traits>

void

print_container_attributes()

{

  // First print out the data structure category.

  print_container_category(typename DS_Traits::container_category());

  // Now print the attributes of the container.

  print_invalidation_guarantee(typename DS_Traits::invalidation_guarantee());

  print_split_join_can_throw(DS_Traits::split_join_can_throw);

  cout << endl << endl;

}

int main()

{

  {

    // Print the attributes of a binary heap.

    typedef

      __gnu_pbds::priority_queue<

      int,

      std::less<int>,

      binary_heap_tag>

      t;

    print_container_attributes<container_traits<t> >();

  }

  {

    // Print the attributes of a binomial heap.

    typedef

      __gnu_pbds::priority_queue<

      int,

      std::less<int>,

      binomial_heap_tag>

      t;

    print_container_attributes<container_traits<t> >();

  }

  {

    // Print the attributes of a redundant-counter binomial heap.

    typedef

      __gnu_pbds::priority_queue<

      int,

      std::less<int>,

      rc_binomial_heap_tag>

      t;

    print_container_attributes<container_traits<t> >();

  }

  {

    // Print the attributes of a pairing heap.

    typedef

      __gnu_pbds::priority_queue<

      int,

      std::less<int>,

      pairing_heap_tag>

      t;

    print_container_attributes<container_traits<t> >();

  }

  {

    /**

     *  Print the attributes of a thin heap.

     */

    typedef

      __gnu_pbds::priority_queue<

      int,

      std::less<int>,

      thin_heap_tag>

      t;

    print_container_attributes<container_traits<t> >();

  }

  return 0;

}