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

  *

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

  *

  * Copyright (C) 2015-2017

  * EMAXA Kutato-fejleszto Kft. (EMAXA Research Ltd.)

  *

  * 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.

  *

  */

 #ifndef LEMON_VF2PP_H

 #define LEMON_VF2PP_H

 ///\ingroup graph_properties

 ///\file

 ///\brief VF2 Plus Plus algorithm.

 #include <lemon/core.h>

 #include <lemon/concepts/graph.h>

 #include <lemon/bits/vf2_internals.h>

 #include <vector>

 #include <algorithm>

 #include <utility>

 namespace lemon {

   ///%VF2 Plus Plus algorithm class \cite VF2PP.

   ///\ingroup graph_isomorphism This class provides an efficient

   ///implementation of the %VF2 Plus Plus algorithm \cite VF2PP

   ///for variants of the (Sub)graph Isomorphism problem.

   ///

   ///There is also a \ref vf2pp() "function-type interface" called

   ///\ref vf2pp() for the %VF2 Plus Plus algorithm, which is probably

   ///more convenient in most use cases.

   ///

   ///\tparam G1 The type of the graph to be embedded.

   ///The default type is \ref ListGraph.

   ///\tparam G2 The type of the graph g1 will be embedded into.

   ///The default type is \ref ListGraph.

   ///\tparam M The type of the NodeMap storing the mapping.

   ///By default, it is G1::NodeMap<G2::Node>

   ///\tparam M1 The type of the NodeMap storing the integer node labels of G1.

   ///The labels must be the numbers {0,1,2,..,K-1}, where K is the number of

   ///different labels. By default, it is G1::NodeMap<int>.

   ///\tparam M2 The type of the NodeMap storing the integer node labels of G2.

   ///The labels must be the numbers {0,1,2,..,K-1}, where K is the number of

   ///different labels. By default, it is G2::NodeMap<int>.

   ///

   ///\sa vf2pp()

 #ifdef DOXYGEN

   template<class G1, class G2, class M, class M1, class M2 >

 #else

   template<class G1 = ListGraph,

            class G2 = ListGraph,

            class M = typename G1::template NodeMap<G2::Node>,

            class M1 = typename G1::template NodeMap<int>,

            class M2 = typename G2::template NodeMap<int> >

 #endif

   class Vf2pp {

     //The graph to be embedded

     const G1 &_g1;

     //The graph into which g1 is to be embedded

     const G2 &_g2;

     //Current depth in the search tree

     int _depth;

     //The current mapping. _mapping[v1]=v2 iff v1 has been mapped to v2,

     //where v1 is a node of G1 and v2 is a node of G2

     M &_mapping;

     //_order[i] is a node of g1 for which a pair is searched if depth=i

     std::vector<typename G1::Node> _order;

     //_conn[v2] = number of covered neighbours of v2

     typename G2::template NodeMap<int> _conn;

     //_currEdgeIts[i] is the last used edge iterator in the i-th

     //depth to find a pair for node _order[i]

     std::vector<typename G2::IncEdgeIt> _currEdgeIts;

     //_rNewLabels1[v] is a pair of form

     //(label; num. of uncov. nodes with such label and no covered neighbours)

     typename G1::template NodeMap<std::vector<std::pair<int,int> > >

     _rNewLabels1;

     //_rInOutLabels1[v] is the number of covered neighbours of v for each label

     //in form (label,number of such labels)

     typename G1::template NodeMap<std::vector<std::pair<int,int> > >

     _rInOutLabels1;

     //_intLabels1[v]==i means that node v has label i in _g1

     //(i is in {0,1,2,..,K-1}, where K is the number of diff. labels)

     M1 &_intLabels1;

     //_intLabels2[v]==i means that node v has label i in _g2

     //(i is in {0,1,2,..,K-1}, where K is the number of diff. labels)

     M2 &_intLabels2;

     //largest label

     const int _maxLabel;

     //lookup tables for manipulating with label class cardinalities

     //(after use they have to be reset to 0..0)

     std::vector<int> _labelTmp1,_labelTmp2;

     MappingType _mapping_type;

     //indicates whether the mapping or the labels must be deleted in the destructor

     bool _deallocMappingAfterUse,_deallocLabelsAfterUse;

     //improved cutting function

     template<MappingType MT>

     bool cutByLabels(const typename G1::Node n1,const typename G2::Node n2) {

       for(typename G2::IncEdgeIt e2(_g2,n2); e2!=INVALID; ++e2) {

         const typename G2::Node currNode=_g2.oppositeNode(n2,e2);

         if(_conn[currNode]>0)

           --_labelTmp1[_intLabels2[currNode]];

         else if(MT!=SUBGRAPH&&_conn[currNode]==0)

           --_labelTmp2[_intLabels2[currNode]];

       }

       bool ret=1;

       if(ret) {

         for(unsigned int i = 0; i < _rInOutLabels1[n1].size(); ++i)

           _labelTmp1[_rInOutLabels1[n1][i].first]+=_rInOutLabels1[n1][i].second;

         if(MT!=SUBGRAPH)

           for(unsigned int i = 0; i < _rNewLabels1[n1].size(); ++i)

             _labelTmp2[_rNewLabels1[n1][i].first]+=_rNewLabels1[n1][i].second;

         switch(MT) {

         case INDUCED:

           for(unsigned int i = 0; i < _rInOutLabels1[n1].size(); ++i)

             if(_labelTmp1[_rInOutLabels1[n1][i].first]>0) {

               ret=0;

               break;

             }

           if(ret)

             for(unsigned int i = 0; i < _rNewLabels1[n1].size(); ++i)

               if(_labelTmp2[_rNewLabels1[n1][i].first]>0) {

                 ret=0;

                 break;

               }

           break;

         case SUBGRAPH:

           for(unsigned int i = 0; i < _rInOutLabels1[n1].size(); ++i)

             if(_labelTmp1[_rInOutLabels1[n1][i].first]>0) {

               ret=0;

               break;

             }

           break;

         case ISOMORPH:

           for(unsigned int i = 0; i < _rInOutLabels1[n1].size(); ++i)

             if(_labelTmp1[_rInOutLabels1[n1][i].first]!=0) {

               ret=0;

               break;

             }

           if(ret)

             for(unsigned int i = 0; i < _rNewLabels1[n1].size(); ++i)

               if(_labelTmp2[_rNewLabels1[n1][i].first]!=0) {

                 ret=0;

                 break;

               }

           break;

         default:

           return false;

         }

         for(unsigned int i = 0; i < _rInOutLabels1[n1].size(); ++i)

           _labelTmp1[_rInOutLabels1[n1][i].first]=0;

         if(MT!=SUBGRAPH)

           for(unsigned int i = 0; i < _rNewLabels1[n1].size(); ++i)

             _labelTmp2[_rNewLabels1[n1][i].first]=0;

       }

       for(typename G2::IncEdgeIt e2(_g2,n2); e2!=INVALID; ++e2) {

         const typename G2::Node currNode=_g2.oppositeNode(n2,e2);

         _labelTmp1[_intLabels2[currNode]]=0;

         if(MT!=SUBGRAPH&&_conn[currNode]==0)

           _labelTmp2[_intLabels2[currNode]]=0;

       }

       return ret;

     }

     //try to exclude the matching of n1 and n2

     template<MappingType MT>

     bool feas(const typename G1::Node n1,const typename G2::Node n2) {

       if(_intLabels1[n1]!=_intLabels2[n2])

         return 0;

       for(typename G1::IncEdgeIt e1(_g1,n1); e1!=INVALID; ++e1) {

         const typename G1::Node& currNode=_g1.oppositeNode(n1,e1);

         if(_mapping[currNode]!=INVALID)

           --_conn[_mapping[currNode]];

       }

       bool isIso=1;

       for(typename G2::IncEdgeIt e2(_g2,n2); e2!=INVALID; ++e2) {

         int& connCurrNode = _conn[_g2.oppositeNode(n2,e2)];

         if(connCurrNode<-1)

           ++connCurrNode;

         else if(MT!=SUBGRAPH&&connCurrNode==-1) {

           isIso=0;

           break;

         }

       }

       if(isIso)

         for(typename G1::IncEdgeIt e1(_g1,n1); e1!=INVALID; ++e1) {

           const typename G2::Node& currNodePair =

             _mapping[_g1.oppositeNode(n1,e1)];

           int& connCurrNodePair=_conn[currNodePair];

           if(currNodePair!=INVALID&&connCurrNodePair!=-1) {

             switch(MT){

             case INDUCED:

             case ISOMORPH:

               isIso=0;

               break;

             case SUBGRAPH:

               if(connCurrNodePair<-1)

                 isIso=0;

               break;

             }

             connCurrNodePair=-1;

           }

         }

       else

         for(typename G1::IncEdgeIt e1(_g1,n1); e1!=INVALID; ++e1) {

           const typename G2::Node currNode=_mapping[_g1.oppositeNode(n1,e1)];

           if(currNode!=INVALID/*&&_conn[currNode]!=-1*/)

             _conn[currNode]=-1;

         }

       return isIso&&cutByLabels<MT>(n1,n2);

     }

     //maps n1 to n2

     void addPair(const typename G1::Node n1,const typename G2::Node n2) {

       _conn[n2]=-1;

       _mapping.set(n1,n2);

       for(typename G2::IncEdgeIt e2(_g2,n2); e2!=INVALID; ++e2) {

         int& currConn = _conn[_g2.oppositeNode(n2,e2)];

         if(currConn!=-1)

           ++currConn;

       }

     }

     //removes mapping of n1 to n2

     void subPair(const typename G1::Node n1,const typename G2::Node n2) {

       _conn[n2]=0;

       _mapping.set(n1,INVALID);

       for(typename G2::IncEdgeIt e2(_g2,n2); e2!=INVALID; ++e2){

         int& currConn = _conn[_g2.oppositeNode(n2,e2)];

         if(currConn>0)

           --currConn;

         else if(currConn==-1)

           ++_conn[n2];

       }

     }

     void processBfsTree(typename G1::Node source,unsigned int& orderIndex,

                          typename G1::template NodeMap<int>& dm1,

                          typename G1::template NodeMap<bool>& added) {

       _order[orderIndex]=source;

       added[source]=1;

       unsigned int endPosOfLevel=orderIndex,

         startPosOfLevel=orderIndex,

         lastAdded=orderIndex;

       typename G1::template NodeMap<int> currConn(_g1,0);

       while(orderIndex<=lastAdded){

         typename G1::Node currNode = _order[orderIndex];

         for(typename G1::IncEdgeIt e(_g1,currNode); e!=INVALID; ++e) {

           typename G1::Node n = _g1.oppositeNode(currNode,e);

           if(!added[n]) {

             _order[++lastAdded]=n;

             added[n]=1;

           }

         }

         if(orderIndex>endPosOfLevel){

           for(unsigned int j = startPosOfLevel; j <= endPosOfLevel; ++j) {

             int minInd=j;

             for(unsigned int i = j+1; i <= endPosOfLevel; ++i)

               if(currConn[_order[i]]>currConn[_order[minInd]]||

                  (currConn[_order[i]]==currConn[_order[minInd]]&&

                   (dm1[_order[i]]>dm1[_order[minInd]]||

                    (dm1[_order[i]]==dm1[_order[minInd]]&&

                     _labelTmp1[_intLabels1[_order[minInd]]]>

                     _labelTmp1[_intLabels1[_order[i]]]))))

                 minInd=i;

             --_labelTmp1[_intLabels1[_order[minInd]]];

             for(typename G1::IncEdgeIt e(_g1,_order[minInd]); e!=INVALID; ++e)

               ++currConn[_g1.oppositeNode(_order[minInd],e)];

             std::swap(_order[j],_order[minInd]);

           }

           startPosOfLevel=endPosOfLevel+1;

           endPosOfLevel=lastAdded;

         }

         ++orderIndex;

       }

     }

     //we will find pairs for the nodes of g1 in this order

     void initOrder(){

       for(typename G2::NodeIt n2(_g2); n2!=INVALID; ++n2)

         ++_labelTmp1[_intLabels2[n2]];

       typename G1::template NodeMap<int> dm1(_g1,0);

       for(typename G1::EdgeIt e(_g1); e!=INVALID; ++e) {

         ++dm1[_g1.u(e)];

         ++dm1[_g1.v(e)];

       }

       typename G1::template NodeMap<bool> added(_g1,0);

       unsigned int orderIndex=0;

       for(typename G1::NodeIt n(_g1); n!=INVALID;) {

         if(!added[n]){

           typename G1::Node minNode = n;

           for(typename G1::NodeIt n1(_g1,minNode); n1!=INVALID; ++n1)

             if(!added[n1] &&

                (_labelTmp1[_intLabels1[minNode]]>

                 _labelTmp1[_intLabels1[n1]]||(dm1[minNode]<dm1[n1]&&

                                              _labelTmp1[_intLabels1[minNode]]==

                                              _labelTmp1[_intLabels1[n1]])))

               minNode=n1;

           processBfsTree(minNode,orderIndex,dm1,added);

         }

         else

           ++n;

       }

       for(unsigned int i = 0; i < _labelTmp1.size(); ++i)

         _labelTmp1[i]=0;

     }

     template<MappingType MT>

     bool extMatch(){

       while(_depth>=0) {

         if(_depth==static_cast<int>(_order.size())) {

           //all nodes of g1 are mapped to nodes of g2

           --_depth;

           return true;

         }

         typename G1::Node& nodeOfDepth = _order[_depth];

         const typename G2::Node& pairOfNodeOfDepth = _mapping[nodeOfDepth];

         typename G2::IncEdgeIt &edgeItOfDepth = _currEdgeIts[_depth];

         //the node of g2 whose neighbours are the candidates for

         //the pair of _order[_depth]

         typename G2::Node currPNode;

         if(edgeItOfDepth==INVALID){

           typename G1::IncEdgeIt fstMatchedE(_g1,nodeOfDepth);

           //if _mapping[_order[_depth]]!=INVALID, we don't need fstMatchedE

           if(pairOfNodeOfDepth==INVALID) {

             for(; fstMatchedE!=INVALID &&

                   _mapping[_g1.oppositeNode(nodeOfDepth,

                                             fstMatchedE)]==INVALID;

                 ++fstMatchedE); //find fstMatchedE, it could be preprocessed

           }

           if(fstMatchedE==INVALID||pairOfNodeOfDepth!=INVALID) {

             //We found no covered neighbours, this means that

             //the graph is not connected (or _depth==0). Each

             //uncovered (and there are some other properties due

             //to the spec. problem types) node of g2 is

             //candidate. We can read the iterator of the last

             //tried node from the match if it is not the first

             //try (match[nodeOfDepth]!=INVALID)

             typename G2::NodeIt n2(_g2);

             //if it's not the first try

             if(pairOfNodeOfDepth!=INVALID) {

               n2=++typename G2::NodeIt(_g2,pairOfNodeOfDepth);

               subPair(nodeOfDepth,pairOfNodeOfDepth);

             }

             for(; n2!=INVALID; ++n2)

               if(MT!=SUBGRAPH) {

                 if(_conn[n2]==0&&feas<MT>(nodeOfDepth,n2))

                   break;

               }

               else if(_conn[n2]>=0&&feas<MT>(nodeOfDepth,n2))

                 break;

             // n2 is the next candidate

             if(n2!=INVALID) {

               addPair(nodeOfDepth,n2);

               ++_depth;

             }

             else // there are no more candidates

               --_depth;

             continue;

           }

           else {

             currPNode=_mapping[_g1.oppositeNode(nodeOfDepth,

                                                 fstMatchedE)];

             edgeItOfDepth=typename G2::IncEdgeIt(_g2,currPNode);

           }

         }

         else {

           currPNode=_g2.oppositeNode(pairOfNodeOfDepth,

                                      edgeItOfDepth);

           subPair(nodeOfDepth,pairOfNodeOfDepth);

           ++edgeItOfDepth;

         }

         for(; edgeItOfDepth!=INVALID; ++edgeItOfDepth) {

           const typename G2::Node currNode =

             _g2.oppositeNode(currPNode, edgeItOfDepth);

           if(_conn[currNode]>0&&feas<MT>(nodeOfDepth,currNode)) {

             addPair(nodeOfDepth,currNode);

             break;

           }

         }

         edgeItOfDepth==INVALID?--_depth:++_depth;

       }

       return false;

     }

     //calculate the lookup table for cutting the search tree

     void initRNew1tRInOut1t(){

       typename G1::template NodeMap<int> tmp(_g1,0);

       for(unsigned int i=0; i<_order.size(); ++i) {

         tmp[_order[i]]=-1;

         for(typename G1::IncEdgeIt e1(_g1,_order[i]); e1!=INVALID; ++e1) {

           const typename G1::Node currNode=_g1.oppositeNode(_order[i],e1);

           if(tmp[currNode]>0)

             ++_labelTmp1[_intLabels1[currNode]];

           else if(tmp[currNode]==0)

             ++_labelTmp2[_intLabels1[currNode]];

         }

         //_labelTmp1[i]=number of neightbours with label i in set rInOut

         //_labelTmp2[i]=number of neightbours with label i in set rNew

         for(typename G1::IncEdgeIt e1(_g1,_order[i]); e1!=INVALID; ++e1) {

           const int& currIntLabel = _intLabels1[_g1.oppositeNode(_order[i],e1)];

           if(_labelTmp1[currIntLabel]>0) {

             _rInOutLabels1[_order[i]]

               .push_back(std::make_pair(currIntLabel,

                                         _labelTmp1[currIntLabel]));

             _labelTmp1[currIntLabel]=0;

           }

           else if(_labelTmp2[currIntLabel]>0) {

             _rNewLabels1[_order[i]].

               push_back(std::make_pair(currIntLabel,_labelTmp2[currIntLabel]));

             _labelTmp2[currIntLabel]=0;

           }

         }

         for(typename G1::IncEdgeIt e1(_g1,_order[i]); e1!=INVALID; ++e1) {

           int& tmpCurrNode=tmp[_g1.oppositeNode(_order[i],e1)];

           if(tmpCurrNode!=-1)

             ++tmpCurrNode;

         }

       }

     }

     int getMaxLabel() const{

       int m=-1;

       for(typename G1::NodeIt n1(_g1); n1!=INVALID; ++n1) {

         const int& currIntLabel = _intLabels1[n1];

         if(currIntLabel>m)

           m=currIntLabel;

       }

       for(typename G2::NodeIt n2(_g2); n2!=INVALID; ++n2) {

         const int& currIntLabel = _intLabels2[n2];

         if(currIntLabel>m)

           m=currIntLabel;

       }

       return m;

     }

   public:

     ///Constructor

     ///Constructor.

     ///\param g1 The graph to be embedded.

     ///\param g2 The graph \e g1 will be embedded into.

     ///\param m The type of the NodeMap storing the mapping.

     ///By default, it is G1::NodeMap<G2::Node>

     ///\param intLabel1 The NodeMap storing the integer node labels of G1.

     ///The labels must be the numbers {0,1,2,..,K-1}, where K is the number of

     ///different labels.

     ///\param intLabel1 The NodeMap storing the integer node labels of G2.

     ///The labels must be the numbers {0,1,2,..,K-1}, where K is the number of

     ///different labels.

     Vf2pp(const G1 &g1, const G2 &g2,M &m, M1 &intLabels1, M2 &intLabels2) :

       _g1(g1), _g2(g2), _depth(0), _mapping(m), _order(countNodes(g1),INVALID),

       _conn(g2,0), _currEdgeIts(countNodes(g1),INVALID), _rNewLabels1(_g1),

       _rInOutLabels1(_g1), _intLabels1(intLabels1) ,_intLabels2(intLabels2),

       _maxLabel(getMaxLabel()), _labelTmp1(_maxLabel+1),_labelTmp2(_maxLabel+1),

       _mapping_type(SUBGRAPH), _deallocMappingAfterUse(0),

       _deallocLabelsAfterUse(0)

     {

       initOrder();

       initRNew1tRInOut1t();

       //reset mapping

       for(typename G1::NodeIt n(g1);n!=INVALID;++n)

         m[n]=INVALID;

     }

     ///Destructor

     ///Destructor.

     ///

     ~Vf2pp()

     {

       if(_deallocMappingAfterUse)

         delete &_mapping;

       if(_deallocLabelsAfterUse) {

         delete &_intLabels1;

         delete &_intLabels2;

       }

     }

     ///Returns the current mapping type.

     ///Returns the current mapping type.

     ///

     MappingType mappingType() const

     {

       return _mapping_type;

     }

     ///Sets the mapping type

     ///Sets the mapping type.

     ///

     ///The mapping type is set to \ref SUBGRAPH by default.

     ///

     ///\sa See \ref MappingType for the possible values.

     void mappingType(MappingType m_type)

     {

       _mapping_type = m_type;

     }

     ///Finds a mapping.

     ///This method finds a mapping from g1 into g2 according to the mapping

     ///type set by \ref mappingType(MappingType) "mappingType()".

     ///

     ///By subsequent calls, it returns all possible mappings one-by-one.

     ///

     ///\retval true if a mapping is found.

     ///\retval false if there is no (more) mapping.

     bool find()

     {

       switch(_mapping_type)

         {

         case SUBGRAPH:

           return extMatch<SUBGRAPH>();

         case INDUCED:

           return extMatch<INDUCED>();

         case ISOMORPH:

           return extMatch<ISOMORPH>();

         default:

           return false;

         }

     }

   };

   template<typename G1, typename G2>

   class Vf2ppWizardBase {

   protected:

     typedef G1 Graph1;

     typedef G2 Graph2;

     const G1 &_g1;

     const G2 &_g2;

     MappingType _mapping_type;

     typedef typename G1::template NodeMap<typename G2::Node> Mapping;

     bool _local_mapping;

     void *_mapping;

     void createMapping() {

       _mapping = new Mapping(_g1);

     }

     bool _local_nodeLabels;

     typedef typename G1::template NodeMap<int> NodeLabels1;

     typedef typename G2::template NodeMap<int> NodeLabels2;

     void *_nodeLabels1, *_nodeLabels2;

     void createNodeLabels() {

       _nodeLabels1 = new NodeLabels1(_g1,0);

       _nodeLabels2 = new NodeLabels2(_g2,0);

     }

     Vf2ppWizardBase(const G1 &g1,const G2 &g2)

       : _g1(g1), _g2(g2), _mapping_type(SUBGRAPH),

         _local_mapping(1), _local_nodeLabels(1) { }

   };

   /// \brief Auxiliary class for the function-type interface of %VF2

   /// Plus Plus algorithm.

   ///

   /// This auxiliary class implements the named parameters of

   /// \ref vf2pp() "function-type interface" of \ref Vf2pp algorithm.

   ///

   /// \warning This class is not to be used directly.

   ///

   /// \tparam TR The traits class that defines various types used by the

   /// algorithm.

   template<typename TR>

   class Vf2ppWizard : public TR {

     typedef TR Base;

     typedef typename TR::Graph1 Graph1;

     typedef typename TR::Graph2 Graph2;

     typedef typename TR::Mapping Mapping;

     typedef typename TR::NodeLabels1 NodeLabels1;

     typedef typename TR::NodeLabels2 NodeLabels2;

     using TR::_g1;

     using TR::_g2;

     using TR::_mapping_type;

     using TR::_mapping;

     using TR::_nodeLabels1;

     using TR::_nodeLabels2;

   public:

     ///Constructor

     Vf2ppWizard(const Graph1 &g1,const Graph2 &g2) : Base(g1,g2) {}

     ///Copy constructor

     Vf2ppWizard(const Base &b) : Base(b) {}

     template<typename T>

     struct SetMappingBase : public Base {

       typedef T Mapping;

       SetMappingBase(const Base &b) : Base(b) {}

     };

     ///\brief \ref named-templ-param "Named parameter" for setting

     ///the mapping.

     ///

     ///\ref named-templ-param "Named parameter" function for setting

     ///the map that stores the found embedding.

     template<typename T>

     Vf2ppWizard< SetMappingBase<T> > mapping(const T &t) {

       Base::_mapping=reinterpret_cast<void*>(const_cast<T*>(&t));

       Base::_local_mapping = 0;

       return Vf2ppWizard<SetMappingBase<T> >(*this);

     }

     template<typename NL1, typename NL2>

     struct SetNodeLabelsBase : public Base {

       typedef NL1 NodeLabels1;

       typedef NL2 NodeLabels2;

       SetNodeLabelsBase(const Base &b) : Base(b) { }

     };

     ///\brief \ref named-templ-param "Named parameter" for setting the

     ///node labels.

     ///

     ///\ref named-templ-param "Named parameter" function for setting

     ///the node labels.

     ///

     ///\param nodeLabels1 A \ref concepts::ReadMap "readable node map"

     ///of g1 with integer values. In case of K different labels, the labels

     ///must be the numbers {0,1,..,K-1}.

     ///\param nodeLabels2 A \ref concepts::ReadMap "readable node map"

     ///of g2 with integer values. In case of K different labels, the labels

     ///must be the numbers {0,1,..,K-1}.

     template<typename NL1, typename NL2>

     Vf2ppWizard< SetNodeLabelsBase<NL1,NL2> >

     nodeLabels(const NL1 &nodeLabels1, const NL2 &nodeLabels2) {

       Base::_local_nodeLabels = 0;

       Base::_nodeLabels1=

         reinterpret_cast<void*>(const_cast<NL1*>(&nodeLabels1));

       Base::_nodeLabels2=

         reinterpret_cast<void*>(const_cast<NL2*>(&nodeLabels2));

       return Vf2ppWizard<SetNodeLabelsBase<NL1,NL2> >

         (SetNodeLabelsBase<NL1,NL2>(*this));

     }

     ///\brief \ref named-templ-param "Named parameter" for setting

     ///the mapping type.

     ///

     ///\ref named-templ-param "Named parameter" for setting

     ///the mapping type.

     ///

     ///The mapping type is set to \ref SUBGRAPH by default.

     ///

     ///\sa See \ref MappingType for the possible values.

     Vf2ppWizard<Base> &mappingType(MappingType m_type) {

       _mapping_type = m_type;

       return *this;

     }

     ///\brief \ref named-templ-param "Named parameter" for setting

     ///the mapping type to \ref INDUCED.

     ///

     ///\ref named-templ-param "Named parameter" for setting

     ///the mapping type to \ref INDUCED.

     Vf2ppWizard<Base> &induced() {

       _mapping_type = INDUCED;

       return *this;

     }

     ///\brief \ref named-templ-param "Named parameter" for setting

     ///the mapping type to \ref ISOMORPH.

     ///

     ///\ref named-templ-param "Named parameter" for setting

     ///the mapping type to \ref ISOMORPH.

     Vf2ppWizard<Base> &iso() {

       _mapping_type = ISOMORPH;

       return *this;

     }

     ///Runs the %VF2 Plus Plus algorithm.

     ///This method runs the VF2 Plus Plus algorithm.

     ///

     ///\retval true if a mapping is found.

     ///\retval false if there is no mapping.

     bool run() {

       if(Base::_local_mapping)

         Base::createMapping();

       if(Base::_local_nodeLabels)

         Base::createNodeLabels();

       Vf2pp<Graph1, Graph2, Mapping, NodeLabels1, NodeLabels2 >

         alg(_g1, _g2, *reinterpret_cast<Mapping*>(_mapping),

             *reinterpret_cast<NodeLabels1*>(_nodeLabels1),

             *reinterpret_cast<NodeLabels2*>(_nodeLabels2));

       alg.mappingType(_mapping_type);

       const bool ret = alg.find();

       if(Base::_local_nodeLabels) {

         delete reinterpret_cast<NodeLabels1*>(_nodeLabels1);

         delete reinterpret_cast<NodeLabels2*>(_nodeLabels2);

       }

       if(Base::_local_mapping)

         delete reinterpret_cast<Mapping*>(_mapping);

       return ret;

     }

     ///Get a pointer to the generated Vf2pp object.

     ///Gives a pointer to the generated Vf2pp object.

     ///

     ///\return Pointer to the generated Vf2pp object.

     ///\warning Don't forget to delete the referred Vf2pp object after use.

     Vf2pp<Graph1, Graph2, Mapping, NodeLabels1, NodeLabels2 >*

     getPtrToVf2ppObject(){

       if(Base::_local_mapping)

         Base::createMapping();

       if(Base::_local_nodeLabels)

         Base::createNodeLabels();

       Vf2pp<Graph1, Graph2, Mapping, NodeLabels1, NodeLabels2 >* ptr =

         new Vf2pp<Graph1, Graph2, Mapping, NodeLabels1, NodeLabels2>

         (_g1, _g2, *reinterpret_cast<Mapping*>(_mapping),

          *reinterpret_cast<NodeLabels1*>(_nodeLabels1),

          *reinterpret_cast<NodeLabels2*>(_nodeLabels2));

       ptr->mappingType(_mapping_type);

       if(Base::_local_mapping)

         ptr->_deallocMappingAfterUse=true;

       if(Base::_local_nodeLabels)

         ptr->_deallocLabelMapsAfterUse=true;

       return ptr;

     }

     ///Counts the number of mappings.

     ///This method counts the number of mappings.

     ///

     /// \return The number of mappings.

     int count() {

       if(Base::_local_mapping)

         Base::createMapping();

       if(Base::_local_nodeLabels)

         Base::createNodeLabels();

       Vf2pp<Graph1, Graph2, Mapping, NodeLabels1, NodeLabels2>

         alg(_g1, _g2, *reinterpret_cast<Mapping*>(_mapping),

             *reinterpret_cast<NodeLabels1*>(_nodeLabels1),

             *reinterpret_cast<NodeLabels2*>(_nodeLabels2));

       alg.mappingType(_mapping_type);

       int ret = 0;

       while(alg.find())

         ++ret;

       if(Base::_local_nodeLabels) {

         delete reinterpret_cast<NodeLabels1*>(_nodeLabels1);

         delete reinterpret_cast<NodeLabels2*>(_nodeLabels2);

       }

       if(Base::_local_mapping)

         delete reinterpret_cast<Mapping*>(_mapping);

       return ret;

     }

   };

   ///Function-type interface for VF2 Plus Plus algorithm.

   /// \ingroup graph_isomorphism

   ///Function-type interface for VF2 Plus Plus algorithm.

   ///

   ///This function has several \ref named-func-param "named parameters"

   ///declared as the members of class \ref Vf2ppWizard.

   ///The following examples show how to use these parameters.

   ///\code

   ///  ListGraph::NodeMap<ListGraph::Node> m(g);

   ///  // Find an embedding of graph g1 into graph g2

   ///  vf2pp(g1,g2).mapping(m).run();

   ///

   ///  // Check whether graphs g1 and g2 are isomorphic

   ///  bool is_iso = vf2pp(g1,g2).iso().run();

   ///

   ///  // Count the number of isomorphisms

   ///  int num_isos = vf2pp(g1,g2).iso().count();

   ///

   ///  // Iterate through all the induced subgraph mappings

   ///  // of graph g1 into g2 using the labels c1 and c2

   ///  auto* myVf2pp = vf2pp(g1,g2).mapping(m).nodeLabels(c1,c2)

   ///  .induced().getPtrToVf2Object();

   ///  while(myVf2pp->find()){

   ///    //process the current mapping m

   ///  }

   ///  delete myVf22pp;

   ///\endcode

   ///\warning Don't forget to put the \ref Vf2ppWizard::run() "run()",

   ///\ref Vf2ppWizard::count() "count()" or

   ///the \ref Vf2ppWizard::getPtrToVf2ppObject() "getPtrToVf2ppObject()"

   ///to the end of the expression.

   ///\sa Vf2ppWizard

   ///\sa Vf2pp

   template<class G1, class G2>

   Vf2ppWizard<Vf2ppWizardBase<G1,G2> > vf2pp(const G1 &g1, const G2 &g2) {

     return Vf2ppWizard<Vf2ppWizardBase<G1,G2> >(g1,g2);

   }

 }

 #endif