/* -*- C++ -*-

 *

 * This file is a part of LEMON, a generic C++ optimization library

 *

 * Copyright (C) 2003-2008

 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

 * (Egervary Research Group on Combinatorial Optimization, 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.

 *

 */

///\ingroup demos

///\file

///\brief LEMON style "Hello World!" program

///

/// This program is intended to be a "Hello World!" program that shows

/// the very basic notions of the LEMON library: \ref graphs "graphs" and

/// \ref maps-page "maps". Click on the links to read more about these.

///

/// \include hello_world.cc

#include <iostream>

#include <lemon/list_graph.h>

using namespace lemon;

typedef ListGraph::Node  Node;

typedef ListGraph::Edge  Edge;

int main()

{

  // Declare the graph itself and a NodeMap, witch will store the characters

  // assigned to the nodes

  ListGraph  graph;

  ListGraph::NodeMap<char>  char_map(graph);

  // Add nodes

  Node  new_node = graph.addNode();

  char_map[new_node] = 'H';

  // Store the start node

  Node  start_node = new_node;

  Node  from_node = new_node;

  new_node = graph.addNode();

  char_map[new_node] = 'e';

  // Here we add the first edge...

  graph.addEdge( from_node, new_node );

  // ... and we add some more nodes and edges to the graph

  from_node = new_node;

  new_node = graph.addNode();

  char_map[new_node] = 'l';

  graph.addEdge( from_node, new_node );

  from_node = new_node;

  new_node = graph.addNode();

  char_map[new_node] = 'l';

  graph.addEdge( from_node, new_node );

  from_node = new_node;

  new_node = graph.addNode();

  char_map[new_node] = 'o';

  graph.addEdge( from_node, new_node );

  from_node = new_node;

  new_node = graph.addNode();

  char_map[new_node] = ' ';

  graph.addEdge( from_node, new_node );

  from_node = new_node;

  new_node = graph.addNode();

  char_map[new_node] = 'W';

  graph.addEdge( from_node, new_node );

  from_node = new_node;

  new_node = graph.addNode();

  char_map[new_node] = 'o';

  graph.addEdge( from_node, new_node );

  from_node = new_node;

  new_node = graph.addNode();

  char_map[new_node] = 'r';

  graph.addEdge( from_node, new_node );

  from_node = new_node;

  new_node = graph.addNode();

  char_map[new_node] = 'l';

  graph.addEdge( from_node, new_node );

  from_node = new_node;

  new_node = graph.addNode();

  char_map[new_node] = 'd';

  graph.addEdge( from_node, new_node );

  from_node = new_node;

  new_node = graph.addNode();

  char_map[new_node] = '\n';

  graph.addEdge( from_node, new_node );

  // iterating

  Node  current_node = start_node;

  while( current_node != INVALID )

  {

    std::cout << char_map[current_node] << std::flush;

    ListGraph::OutEdgeIt  edge(graph, current_node);

    if( edge != INVALID )

      current_node = graph.target( edge );

    else

      current_node = INVALID;

  }

  return 0;

}