mirror of
https://github.com/boostorg/graph.git
synced 2025-05-09 23:14:00 +00:00
126 lines
3.7 KiB
C++
126 lines
3.7 KiB
C++
//=======================================================================
|
|
// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
|
|
// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
|
|
//
|
|
// This file is part of the Boost Graph Library
|
|
//
|
|
// You should have received a copy of the License Agreement for the
|
|
// Boost Graph 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 <boost/config.hpp>
|
|
#include <iostream>
|
|
#include <vector>
|
|
#include <algorithm>
|
|
#include <utility>
|
|
#include <boost/graph/adjacency_list.hpp>
|
|
#include <boost/pending/disjoint_sets.hpp>
|
|
#include <boost/graph/incremental_components.hpp>
|
|
|
|
/*
|
|
|
|
This example shows how to use the disjoint set data structure
|
|
to compute the connected components of an undirected, changing
|
|
graph.
|
|
|
|
Sample output:
|
|
|
|
An undirected graph:
|
|
0 <--> 1 4
|
|
1 <--> 0 4
|
|
2 <--> 5
|
|
3 <-->
|
|
4 <--> 1 0
|
|
5 <--> 2
|
|
|
|
representative[0] = 1
|
|
representative[1] = 1
|
|
representative[2] = 5
|
|
representative[3] = 3
|
|
representative[4] = 1
|
|
representative[5] = 5
|
|
|
|
component 0 contains: 4 1 0
|
|
component 1 contains: 3
|
|
component 2 contains: 5 2
|
|
|
|
*/
|
|
|
|
using namespace std;
|
|
|
|
int main(int , char* [])
|
|
{
|
|
using namespace boost;
|
|
typedef adjacency_list <vecS, vecS, undirectedS> Graph;
|
|
typedef graph_traits<Graph>::vertex_descriptor Vertex;
|
|
typedef graph_traits<Graph>::vertices_size_type size_type;
|
|
|
|
const int N = 6;
|
|
Graph G(N);
|
|
|
|
std::vector<size_type> rank(num_vertices(G));
|
|
std::vector<Vertex> parent(num_vertices(G));
|
|
// VC++ version of std::vector has no ::pointer, so
|
|
// I use ::value_type* instead.
|
|
typedef std::vector<size_type>::value_type* Rank;
|
|
typedef std::vector<Vertex>::value_type* Parent;
|
|
disjoint_sets<Rank, Parent> ds(&rank[0], &parent[0]);
|
|
|
|
initialize_incremental_components(G, ds);
|
|
incremental_components(G, ds);
|
|
|
|
graph_traits<Graph>::edge_descriptor e;
|
|
bool flag;
|
|
boost::tie(e,flag) = add_edge(0, 1, G);
|
|
ds.union_set(0,1);
|
|
|
|
boost::tie(e,flag) = add_edge(1, 4, G);
|
|
ds.union_set(1,4);
|
|
|
|
boost::tie(e,flag) = add_edge(4, 0, G);
|
|
ds.union_set(4,0);
|
|
|
|
boost::tie(e,flag) = add_edge(2, 5, G);
|
|
ds.union_set(2,5);
|
|
|
|
cout << "An undirected graph:" << endl;
|
|
print_graph(G, get(vertex_index, G));
|
|
cout << endl;
|
|
|
|
graph_traits<Graph>::vertex_iterator i,end;
|
|
for (boost::tie(i, end) = vertices(G); i != end; ++i)
|
|
cout << "representative[" << *i << "] = " <<
|
|
ds.find_set(*i) << endl;;
|
|
cout << endl;
|
|
|
|
typedef component_index<unsigned int> Components;
|
|
Components components(&parent[0], &parent[0] + parent.size());
|
|
|
|
for (Components::size_type c = 0; c < components.size(); ++c) {
|
|
cout << "component " << c << " contains: ";
|
|
Components::value_type::iterator
|
|
j = components[c].begin(),
|
|
jend = components[c].end();
|
|
for ( ; j != jend; ++j)
|
|
cout << *j << " ";
|
|
cout << endl;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|