2021-10-05 21:37:46 +02:00

125 lines
3.2 KiB
C++

//=======================================================================
// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//=======================================================================
#include <boost/config.hpp>
#include <assert.h>
#include <iostream>
#include <vector>
#include <algorithm>
#include <utility>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/depth_first_search.hpp>
#include <boost/graph/visitors.hpp>
/*
This calculates the discover finishing time.
Sample Output
Tree edge: 0 --> 2
Tree edge: 2 --> 1
Back edge: 1 --> 1
Finish edge: 1 --> 1
Tree edge: 1 --> 3
Back edge: 3 --> 1
Finish edge: 3 --> 1
Tree edge: 3 --> 4
Back edge: 4 --> 0
Finish edge: 4 --> 0
Back edge: 4 --> 1
Finish edge: 4 --> 1
Forward or cross edge: 2 --> 3
Finish edge: 2 --> 3
Finish edge: 0 --> 2
1 10
3 8
2 9
4 7
5 6
*/
using namespace boost;
using namespace std;
template < class VisitorList >
struct edge_categorizer : public dfs_visitor< VisitorList >
{
typedef dfs_visitor< VisitorList > Base;
edge_categorizer(const VisitorList& v = null_visitor()) : Base(v) {}
template < class Edge, class Graph > void tree_edge(Edge e, Graph& G)
{
cout << "Tree edge: " << source(e, G) << " --> " << target(e, G)
<< endl;
Base::tree_edge(e, G);
}
template < class Edge, class Graph > void back_edge(Edge e, Graph& G)
{
cout << "Back edge: " << source(e, G) << " --> " << target(e, G)
<< endl;
Base::back_edge(e, G);
}
template < class Edge, class Graph >
void forward_or_cross_edge(Edge e, Graph& G)
{
cout << "Forward or cross edge: " << source(e, G) << " --> "
<< target(e, G) << endl;
Base::forward_or_cross_edge(e, G);
}
template < class Edge, class Graph > void finish_edge(Edge e, Graph& G)
{
cout << "Finish edge: " << source(e, G) << " --> " << target(e, G)
<< endl;
Base::finish_edge(e, G);
}
};
template < class VisitorList >
edge_categorizer< VisitorList > categorize_edges(const VisitorList& v)
{
return edge_categorizer< VisitorList >(v);
}
int main(int, char*[])
{
using namespace boost;
typedef adjacency_list<> Graph;
Graph G(5);
add_edge(0, 2, G);
add_edge(1, 1, G);
add_edge(1, 3, G);
add_edge(2, 1, G);
add_edge(2, 3, G);
add_edge(3, 1, G);
add_edge(3, 4, G);
add_edge(4, 0, G);
add_edge(4, 1, G);
typedef graph_traits< Graph >::vertices_size_type size_type;
std::vector< size_type > d(num_vertices(G));
std::vector< size_type > f(num_vertices(G));
int t = 0;
depth_first_search(G,
visitor(categorize_edges(
make_pair(stamp_times(&d[0], t, on_discover_vertex()),
stamp_times(&f[0], t, on_finish_vertex())))));
std::vector< size_type >::iterator i, j;
for (i = d.begin(), j = f.begin(); i != d.end(); ++i, ++j)
cout << *i << " " << *j << endl;
return 0;
}