From 483eb2f56657e8e7f419ab1a4fab8dce9ade8609 Mon Sep 17 00:00:00 2001
From: Daniel Baumann <daniel.baumann@progress-linux.org>
Date: Sat, 27 Apr 2024 20:24:20 +0200
Subject: Adding upstream version 14.2.21.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
---
 .../libs/graph/example/incremental_components.cpp  | 119 +++++++++++++++++++++
 1 file changed, 119 insertions(+)
 create mode 100644 src/boost/libs/graph/example/incremental_components.cpp

(limited to 'src/boost/libs/graph/example/incremental_components.cpp')

diff --git a/src/boost/libs/graph/example/incremental_components.cpp b/src/boost/libs/graph/example/incremental_components.cpp
new file mode 100644
index 00000000..f8f156ef
--- /dev/null
+++ b/src/boost/libs/graph/example/incremental_components.cpp
@@ -0,0 +1,119 @@
+//=======================================================================
+// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
+// Copyright 2009 Trustees of Indiana University.
+// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek, Michael Hansen
+//
+// 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 <iostream>
+#include <vector>
+
+#include <boost/foreach.hpp>
+#include <boost/graph/adjacency_list.hpp>
+#include <boost/graph/graph_utility.hpp>
+#include <boost/graph/incremental_components.hpp>
+#include <boost/pending/disjoint_sets.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 boost;
+
+int main(int argc, char* argv[]) 
+{
+  typedef adjacency_list <vecS, vecS, undirectedS> Graph;
+  typedef graph_traits<Graph>::vertex_descriptor Vertex;
+  typedef graph_traits<Graph>::vertices_size_type VertexIndex;
+
+  const int VERTEX_COUNT = 6;
+  Graph graph(VERTEX_COUNT);
+
+  std::vector<VertexIndex> rank(num_vertices(graph));
+  std::vector<Vertex> parent(num_vertices(graph));
+
+  typedef VertexIndex* Rank;
+  typedef Vertex* Parent;
+
+  disjoint_sets<Rank, Parent> ds(&rank[0], &parent[0]);
+
+  initialize_incremental_components(graph, ds);
+  incremental_components(graph, ds);
+
+  graph_traits<Graph>::edge_descriptor edge;
+  bool flag;
+
+  boost::tie(edge, flag) = add_edge(0, 1, graph);
+  ds.union_set(0,1);
+
+  boost::tie(edge, flag) = add_edge(1, 4, graph);
+  ds.union_set(1,4);
+
+  boost::tie(edge, flag) = add_edge(4, 0, graph);
+  ds.union_set(4,0);
+
+  boost::tie(edge, flag) = add_edge(2, 5, graph);
+  ds.union_set(2,5);
+    
+  std::cout << "An undirected graph:" << std::endl;
+  print_graph(graph, get(boost::vertex_index, graph));
+  std::cout << std::endl;
+    
+  BOOST_FOREACH(Vertex current_vertex, vertices(graph)) {
+    std::cout << "representative[" << current_vertex << "] = " <<
+      ds.find_set(current_vertex) << std::endl;
+  }
+
+  std::cout << std::endl;
+
+  typedef component_index<VertexIndex> Components;
+
+  // NOTE: Because we're using vecS for the graph type, we're
+  // effectively using identity_property_map for a vertex index map.
+  // If we were to use listS instead, the index map would need to be
+  // explicitly passed to the component_index constructor.
+  Components components(parent.begin(), parent.end());
+
+  // Iterate through the component indices
+  BOOST_FOREACH(VertexIndex current_index, components) {
+    std::cout << "component " << current_index << " contains: ";
+
+    // Iterate through the child vertex indices for [current_index]
+    BOOST_FOREACH(VertexIndex child_index,
+                  components[current_index]) {
+      std::cout << child_index << " ";
+    }
+
+    std::cout << std::endl;
+  }
+
+  return (0);
+}
+
-- 
cgit v1.2.3