/* -*- 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, 0);

  DiEulerIt<Digraph> e(g);

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

  typename Digraph::Node lastNode = g.target(e);

  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, 0);

  EulerIt<Graph> e(g);

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

  typename Graph::Node lastNode = g.v(e);

  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;

}