COIN-OR::LEMON - Graph Library

source: lemon-0.x/demo/dijkstra_demo.cc @ 1610:893dacc1866c

Last change on this file since 1610:893dacc1866c was 1583:2b329fd595ef, checked in by athos, 14 years ago

Documented some more demo programs.

File size: 2.7 KB
Line 
1/* -*- C++ -*-
2 * demo/lp_maxflow_demo.cc - Part of LEMON, a generic C++ optimization library
3 *
4 * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
5 * (Egervary Research Group on Combinatorial Optimization, EGRES).
6 *
7 * Permission to use, modify and distribute this software is granted
8 * provided that this copyright notice appears in all copies. For
9 * precise terms see the accompanying LICENSE file.
10 *
11 * This software is provided "AS IS" with no warranty of any kind,
12 * express or implied, and with no claim as to its suitability for any
13 * purpose.
14 *
15 */
16
17///\ingroup demos
18///\file
19///\brief Demonstrating LEMON implementation of the Dijkstra algorithm
20///
21/// Dijkstra's algorithm computes shortest paths between two nodes in
22/// a graph with edge lengths. Here we only show some of the
23/// facilities supplied by our implementation: for the detailed
24/// documentation of the LEMON Dijkstra class read \ref lemon::Dijkstra "this".
25
26#include <iostream>
27
28#include <lemon/list_graph.h>
29#include <lemon/dijkstra.h>
30//#include <lemon/graph_writer.h>
31
32using namespace lemon;
33
34
35int main (int, char*[])
36{
37
38    typedef ListGraph Graph;
39    typedef Graph::Node Node;
40    typedef Graph::Edge Edge;
41    typedef Graph::EdgeMap<int> LengthMap;
42
43    Graph g;
44
45    //An example from Ahuja's book
46
47    Node s=g.addNode();
48    Node v2=g.addNode();
49    Node v3=g.addNode();
50    Node v4=g.addNode();
51    Node v5=g.addNode();
52    Node t=g.addNode();
53
54    Edge s_v2=g.addEdge(s, v2);
55    Edge s_v3=g.addEdge(s, v3);
56    Edge v2_v4=g.addEdge(v2, v4);
57    Edge v2_v5=g.addEdge(v2, v5);
58    Edge v3_v5=g.addEdge(v3, v5);
59    Edge v4_t=g.addEdge(v4, t);
60    Edge v5_t=g.addEdge(v5, t);
61 
62    LengthMap len(g);
63
64    len.set(s_v2, 10);
65    len.set(s_v3, 10);
66    len.set(v2_v4, 5);
67    len.set(v2_v5, 8);
68    len.set(v3_v5, 5);
69    len.set(v4_t, 8);
70    len.set(v5_t, 8);
71
72    std::cout << "This program is a simple demo of the LEMON Dijkstra class."<<std::endl;
73    std::cout << "We calculate the shortest path from node s to node t in a graph."<<std::endl;
74    std::cout <<std::endl;
75
76
77    std::cout << "The id of s is " << g.id(s)<< ", the id of t is " << g.id(t)<<"."<<std::endl;
78
79    std::cout << "Dijkstra algorithm demo..." << std::endl;
80
81
82    Dijkstra<Graph, LengthMap> dijkstra_test(g,len);
83   
84    dijkstra_test.run(s);
85
86   
87    std::cout << "The distance of node t from node s: " << dijkstra_test.dist(t)<<std::endl;
88
89    std::cout << "The shortest path from s to t goes through the following nodes (the first one is t, the last one is s): "<<std::endl;
90
91    for (Node v=t;v != s; v=dijkstra_test.predNode(v)){
92        std::cout << g.id(v) << "<-";
93    }
94    std::cout << g.id(s) << std::endl; 
95   
96
97    return 0;
98}
99
100
101
102
103
104
105
106
107
Note: See TracBrowser for help on using the repository browser.