View source for CPP/Boost/BGL/IndirectPriorityQueue

==IndirectPriorityQueue.cpp==
<source lang="cpp">
#include <iostream>
#include <iomanip>

#include <boost/graph/grid_graph.hpp>
#include <boost/graph/detail/d_ary_heap.hpp>
#include <boost/property_map/property_map.hpp>

#include <cstdlib>

template <typename TQueue>
static void OutputQueue(TQueue queue);

int main(int, char*[])
{
  srand((unsigned int)time(NULL));

  boost::array<std::size_t, 2> lengths = { { 5,5 } };
  typedef boost::grid_graph<2> GraphType;
  GraphType graph(lengths);
  typedef boost::graph_traits<GraphType>::vertex_descriptor Vertex;
  typedef boost::property_map<GraphType, boost::vertex_index_t>::const_type GridIndexMapType;
  GridIndexMapType gridIndexMap(get(boost::vertex_index, graph));

  typedef boost::vector_property_map<std::size_t, GridIndexMapType> IndexInHeapMap;
  IndexInHeapMap index_in_heap(gridIndexMap);

  typedef boost::graph_traits<GraphType>::vertex_iterator VertexIteratorType;

  typedef boost::vector_property_map<float, GridIndexMapType> PriorityMapType;
  PriorityMapType priorityMap(gridIndexMap);
  VertexIteratorType vertexIterator, vertexIteratorEnd;

  typedef std::greater<float> ComparisonFunctor;
  typedef boost::d_ary_heap_indirect<Vertex, 4, IndexInHeapMap, PriorityMapType, ComparisonFunctor > MutableQueueType;

  ComparisonFunctor comparisonFunctor;
  MutableQueueType mutableQueue(priorityMap, index_in_heap, comparisonFunctor);

  std::cout << "There are " << mutableQueue.size() << " items in the queue." << std::endl;

  // Add random values to the vertices and add them to the queue
  for( tie(vertexIterator, vertexIteratorEnd) = vertices(graph); vertexIterator != vertexIteratorEnd; ++vertexIterator)
  {
    put(priorityMap, *vertexIterator, rand() % 1000);
  }

  for( tie(vertexIterator, vertexIteratorEnd) = vertices(graph); vertexIterator != vertexIteratorEnd; ++vertexIterator)
  {
    mutableQueue.push(*vertexIterator);
  }

  std::cout << "There are " << mutableQueue.size() << " items in the queue." << std::endl;

  std::cout << "The priority queue is: " << std::endl;
  OutputQueue(mutableQueue);

  // Insert another set of random values for each vertex
  for( tie(vertexIterator, vertexIteratorEnd) = vertices(graph); vertexIterator != vertexIteratorEnd; ++vertexIterator)
  {
    put(priorityMap, *vertexIterator, rand() % 1000);
  }

  for( tie(vertexIterator, vertexIteratorEnd) = vertices(graph); vertexIterator != vertexIteratorEnd; ++vertexIterator)
  {
    mutableQueue.push(*vertexIterator);
  }

  std::cout << "There are " << mutableQueue.size() << " items in the queue." << std::endl;

  std::cout << "The priority queue is: " << std::endl;
  OutputQueue(mutableQueue);

  std::cout << std::endl;

  return 0;
}

template <typename TQueue>
static void OutputQueue(TQueue queue)
{
  while( ! queue.empty() )
  {
    typename TQueue::value_type u = queue.top();

    // These two lines are equivalent
    std::cout << "vertex: " << u[0] << " " << u[1] << " priority: " << get(queue.keys(), u) << std::endl;

    queue.pop();
  }
}

/* Output:
There are 0 items in the queue.
There are 25 items in the queue.
The priority queue is: 
vertex: 4 3 priority: 989
vertex: 3 2 priority: 976
vertex: 0 1 priority: 937
vertex: 1 4 priority: 824
vertex: 0 2 priority: 805
vertex: 1 0 priority: 770
vertex: 4 2 priority: 770
vertex: 4 4 priority: 733
vertex: 2 2 priority: 623
vertex: 0 4 priority: 566
vertex: 3 0 priority: 513
vertex: 4 0 priority: 494
vertex: 2 3 priority: 418
vertex: 3 1 priority: 411
vertex: 1 1 priority: 408
vertex: 0 3 priority: 378
vertex: 3 3 priority: 300
vertex: 3 4 priority: 286
vertex: 0 0 priority: 206
vertex: 2 1 priority: 198
vertex: 1 2 priority: 159
vertex: 2 0 priority: 157
vertex: 2 4 priority: 108
vertex: 1 3 priority: 103
vertex: 4 1 priority: 5
There are 50 items in the queue.
The priority queue is: 
vertex: 3 0 priority: 998
vertex: 3 2 priority: 979
vertex: 3 2 priority: 979
vertex: 2 4 priority: 920
vertex: 0 1 priority: 853
vertex: 0 1 priority: 853
vertex: 3 0 priority: 998
vertex: 4 4 priority: 842
vertex: 2 2 priority: 830
vertex: 2 2 priority: 830
vertex: 3 3 priority: 811
vertex: 3 3 priority: 811
vertex: 0 2 priority: 781
vertex: 0 2 priority: 781
vertex: 1 1 priority: 556
vertex: 4 0 priority: 517
vertex: 4 0 priority: 517
vertex: 4 3 priority: 464
vertex: 4 3 priority: 464
vertex: 3 1 priority: 363
vertex: 3 1 priority: 363
vertex: 0 4 priority: 345
vertex: 1 1 priority: 556
vertex: 0 4 priority: 345
vertex: 1 2 priority: 300
vertex: 1 2 priority: 300
vertex: 4 4 priority: 842
vertex: 2 1 priority: 287
vertex: 2 1 priority: 287
vertex: 2 3 priority: 222
vertex: 2 3 priority: 222
vertex: 1 0 priority: 197
vertex: 2 4 priority: 920
vertex: 1 0 priority: 197
vertex: 1 4 priority: 189
vertex: 1 4 priority: 189
vertex: 0 3 priority: 187
vertex: 0 3 priority: 187
vertex: 1 3 priority: 136
vertex: 1 3 priority: 136
vertex: 0 0 priority: 119
vertex: 0 0 priority: 119
vertex: 2 0 priority: 118
vertex: 2 0 priority: 118
vertex: 3 4 priority: 115
vertex: 3 4 priority: 115
vertex: 4 1 priority: 70
vertex: 4 1 priority: 70
vertex: 4 2 priority: 63
vertex: 4 2 priority: 63

*/

</source>

==CMakeLists.txt==
<source lang="cmake">
cmake_minimum_required(VERSION 2.6)

Project(IndirectPriorityQueue)

set(Boost_USE_MULTITHREADED ON)
FIND_PACKAGE(Boost 1.38 COMPONENTS)

INCLUDE_DIRECTORIES(${INCLUDE_DIRECTORIES} ${Boost_INCLUDE_DIRS})
LINK_DIRECTORIES(${LINK_DIRECTORIES} ${Boost_LIBRARY_DIRS})

ADD_EXECUTABLE(IndirectPriorityQueue IndirectPriorityQueue.cpp)

</source>