/* -*- mode: C++; indent-tabs-mode: nil; -*-

  *

  * This file is a part of LEMON, a generic C++ optimization library.

  *

  * Copyright (C) 2003-2009

  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

  * (Egervary Research Group on Combinatorial Optimization, EGRES).

  *

  * Permission to use, modify and distribute this software is granted

  * provided that this copyright notice appears in all copies. For

  * precise terms see the accompanying LICENSE file.

  *

  * This software is provided "AS IS" with no warranty of any kind,

  * express or implied, and with no claim as to its suitability for any

  * purpose.

  *

  */

 #include <lemon/euler.h>

 #include <lemon/list_graph.h>

 #include <test/test_tools.h>

 using namespace lemon;

 template <typename Digraph>

 void checkDiEulerIt(const Digraph& g)

 {

   typename Digraph::template ArcMap<int> visitationNumber(g);

   DiEulerIt<Digraph> e(g);

   typename Digraph::Node firstNode = g.source(e);

   typename Digraph::Node lastNode;

   for (; e != INVALID; ++e)

   {

     if (e != INVALID)

     {

       lastNode = g.target(e);

     }

     ++visitationNumber[e];

   }

   check(firstNode == lastNode,

       "checkDiEulerIt: first and last node are not the same");

   for (typename Digraph::ArcIt a(g); a != INVALID; ++a)

   {

     check(visitationNumber[a] == 1,

         "checkDiEulerIt: not visited or multiple times visited arc found");

   }

 }

 template <typename Graph>

 void checkEulerIt(const Graph& g)

 {

   typename Graph::template EdgeMap<int> visitationNumber(g);

   EulerIt<Graph> e(g);

   typename Graph::Node firstNode = g.u(e);

   typename Graph::Node lastNode;

   for (; e != INVALID; ++e)

   {

     if (e != INVALID)

     {

       lastNode = g.v(e);

     }

     ++visitationNumber[e];

   }

   check(firstNode == lastNode,

       "checkEulerIt: first and last node are not the same");

   for (typename Graph::EdgeIt e(g); e != INVALID; ++e)

   {

     check(visitationNumber[e] == 1,

         "checkEulerIt: not visited or multiple times visited edge found");

   }

 }

 int main()

 {

   typedef ListDigraph Digraph;

   typedef ListGraph Graph;

   Digraph digraphWithEulerianCircuit;

   {

     Digraph& g = digraphWithEulerianCircuit;

     Digraph::Node n0 = g.addNode();

     Digraph::Node n1 = g.addNode();

     Digraph::Node n2 = g.addNode();

     g.addArc(n0, n1);

     g.addArc(n1, n0);

     g.addArc(n1, n2);

     g.addArc(n2, n1);

   }

   Digraph digraphWithoutEulerianCircuit;

   {

     Digraph& g = digraphWithoutEulerianCircuit;

     Digraph::Node n0 = g.addNode();

     Digraph::Node n1 = g.addNode();

     Digraph::Node n2 = g.addNode();

     g.addArc(n0, n1);

     g.addArc(n1, n0);

     g.addArc(n1, n2);

   }

   Graph graphWithEulerianCircuit;

   {

     Graph& g = graphWithEulerianCircuit;

     Graph::Node n0 = g.addNode();

     Graph::Node n1 = g.addNode();

     Graph::Node n2 = g.addNode();

     g.addEdge(n0, n1);

     g.addEdge(n1, n2);

     g.addEdge(n2, n0);

   }

   Graph graphWithoutEulerianCircuit;

   {

     Graph& g = graphWithoutEulerianCircuit;

     Graph::Node n0 = g.addNode();

     Graph::Node n1 = g.addNode();

     Graph::Node n2 = g.addNode();

     g.addEdge(n0, n1);

     g.addEdge(n1, n2);

   }

   checkDiEulerIt(digraphWithEulerianCircuit);

   checkEulerIt(graphWithEulerianCircuit);

   check(eulerian(digraphWithEulerianCircuit),

       "this graph should have an Eulerian circuit");

   check(!eulerian(digraphWithoutEulerianCircuit),

       "this graph should not have an Eulerian circuit");

   check(eulerian(graphWithEulerianCircuit),

       "this graph should have an Eulerian circuit");

   check(!eulerian(graphWithoutEulerianCircuit),

       "this graph should have an Eulerian circuit");

   return 0;

 }