71 lines
1.9 KiB
C++
71 lines
1.9 KiB
C++
//=======================================================================
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// Copyright 2007 Aaron Windsor
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//
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// Distributed under the Boost Software License, Version 1.0. (See
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// accompanying file LICENSE_1_0.txt or copy at
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// http://www.boost.org/LICENSE_1_0.txt)
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//=======================================================================
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#include <iostream>
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#include <boost/graph/adjacency_list.hpp>
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#include <boost/graph/boyer_myrvold_planar_test.hpp>
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int main(int argc, char** argv)
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{
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// This program illustrates a simple use of boyer_myrvold_planar_embedding
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// as a simple yes/no test for planarity.
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using namespace boost;
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typedef adjacency_list<vecS,
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vecS,
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undirectedS,
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property<vertex_index_t, int>
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> graph;
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graph K_4(4);
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add_edge(0, 1, K_4);
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add_edge(0, 2, K_4);
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add_edge(0, 3, K_4);
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add_edge(1, 2, K_4);
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add_edge(1, 3, K_4);
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add_edge(2, 3, K_4);
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if (boyer_myrvold_planarity_test(K_4))
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std::cout << "K_4 is planar." << std::endl;
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else
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std::cout << "ERROR! K_4 should have been recognized as planar!"
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<< std::endl;
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graph K_5(5);
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add_edge(0, 1, K_5);
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add_edge(0, 2, K_5);
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add_edge(0, 3, K_5);
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add_edge(0, 4, K_5);
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add_edge(1, 2, K_5);
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add_edge(1, 3, K_5);
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add_edge(1, 4, K_5);
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add_edge(2, 3, K_5);
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add_edge(2, 4, K_5);
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// We've almost created a K_5 - it's missing one edge - so it should still
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// be planar at this point.
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if (boyer_myrvold_planarity_test(K_5))
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std::cout << "K_5 (minus an edge) is planar." << std::endl;
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else
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std::cout << "ERROR! K_5 with one edge missing should"
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<< " have been recognized as planar!" << std::endl;
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// Now add the final edge...
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add_edge(3, 4, K_5);
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if (boyer_myrvold_planarity_test(K_5))
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std::cout << "ERROR! K_5 was recognized as planar!" << std::endl;
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else
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std::cout << "K_5 is not planar." << std::endl;
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return 0;
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}
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