forgot this

[SVN r7745]
2026-02-01 08:32:11 +00:00 · 2000-09-19 18:36:43 +00:00
parent 993ce509b7
commit 29f146132d
1 changed files with 138 additions and 0 deletions
--- a/examples/city_visitor.cpp
+++ b/examples/city_visitor.cpp
@@ -0,0 +1,138 @@
+//
+//=======================================================================
+// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
+// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
+//
+// This file is part of the Generic Graph Component Library
+//
+// You should have received a copy of the License Agreement for the
+// Generic Graph Component Library along with the software;  see the
+// file LICENSE.  If not, contact Office of Research, University of Notre
+// Dame, Notre Dame, IN  46556.
+//
+// Permission to modify the code and to distribute modified code is
+// granted, provided the text of this NOTICE is retained, a notice that
+// the code was modified is included with the above COPYRIGHT NOTICE and
+// with the COPYRIGHT NOTICE in the LICENSE file, and that the LICENSE
+// file is distributed with the modified code.
+//
+// LICENSOR MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED.
+// By way of example, but not limitation, Licensor MAKES NO
+// REPRESENTATIONS OR WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY
+// PARTICULAR PURPOSE OR THAT THE USE OF THE LICENSED SOFTWARE COMPONENTS
+// OR DOCUMENTATION WILL NOT INFRINGE ANY PATENTS, COPYRIGHTS, TRADEMARKS
+// OR OTHER RIGHTS.
+//=======================================================================
+//
+
+#include <iostream>
+#include <vector>
+#include <string>
+#include <boost/graph/adjacency_list.hpp>
+#include <boost/graph/depth_first_search.hpp>
+#include <boost/graph/breadth_first_search.hpp>
+#include <boost/property_accessor.hpp>
+
+
+/*
+  Example of using a visitor with the depth first search 
+    and breadth first search algorithm
+
+  Sacramento ---- Reno ---- Salt Lake City
+     |
+  San Francisco
+     |
+  San Jose ---- Fresno
+     |
+  Los Angeles ---- Los Vegas ---- Pheonix
+     |
+  San Diego  
+
+
+  The visitor has three main functions: 
+  
+  discover(u) is invoked when the algorithm first arrives at the
+    vertex u. This will happen in the depth first or breadth first
+    order depending on which algorithm you use.
+
+  process(e) is invoked when the algorithm first checks an edge to see
+    whether it has already been there. Whether using BFS or DFS, all
+    the edges of vertex u are examined immediately after the call to
+    visit(u).
+
+  finish(u) is called when after all the vertices reachable from vertex
+    u have already been visited.    
+
+ */
+
+using namespace std;
+using namespace boost;
+
+struct city_visitor
+ : public null_visitor
+{
+
+  city_visitor(string* n) : names(n) { }
+
+  template <class Vertex>
+  inline void discover(Vertex u) {
+    cout << endl << "arriving at " << names[u] << endl
+	 << "  neighboring cities are: ";
+  }
+
+  template <class Edge, class Graph>
+  inline void process(Edge e, Graph& g) {
+    cout << names[ target(e,g) ] << ", ";
+  }
+
+  template <class Vertex>
+  inline void finish(Vertex u) {
+    cout << endl << "finished with " << names[u] << endl;
+  }
+
+  string* names;
+};
+
+
+
+int main(int argc, char* argv[]) 
+{
+
+  enum { SanJose, SanFran, LA, SanDiego, Fresno, LosVegas, Reno,
+	 Sacramento, SaltLake, Pheonix, N };
+
+  string names[] = { "San Jose", "San Francisco",  "San Jose",
+                     "San Francisco", "Los Angeles", "San Diego", 
+                     "Fresno", "Los Vegas", "Reno", "Sacramento",
+                     "Salt Lake City", "Pheonix" };
+
+  typedef std::pair<int,int> E;
+  E edge_array[] = { E(Sacramento, Reno), E(Sacramento, SanFran),
+		     E(Reno, SaltLake),
+		     E(SanFran, SanJose),
+		     E(SanJose, Fresno), E(SanJose, LA),
+		     E(LA, LosVegas), E(LA, SanDiego),
+		     E(LosVegas, Pheonix) };
+
+  /* Create the graph type we want. */
+  typedef adjacency_list<vecS, vecS, undirectedS> Graph;
+  Graph G(N, edge_array, edge_array + sizeof(edge_array)/sizeof(E));
+
+  /* DFS and BFS need to "color" the vertices */
+  typedef vector<default_color_type> colors_t;
+  colors_t colors(N);
+
+  cout << "*** Depth First ***" << endl;
+  depth_first_search(G, city_visitor(names), colors.begin());
+  cout << endl;
+
+  /* Get the source vertex */
+  boost::graph_traits<Graph>::vertex_descriptor 
+    s = vertex(SanJose,G);
+
+  cout << "*** Breadth First ***" << endl;
+  breadth_first_search(G, s, city_visitor(names), colors.begin());
+
+  //end
+  return 0;
+}