#ifndef _REDUCTION_H#define _REDUCTION_H#include "Population.h"class Reducer {  friend class MOEA; public:  MOEADefineIdentity("Reducer", "R", 500);  Reducer() : ppop1(NULL), ppop2(NULL) { }  virtual ~Reducer() { }  virtual void initialize(POP* p1, int sz1, POP* p2=0, int sz2=0) {     ppop1=p1; ppop2=p2; pop1_maxSz = sz1; pop2_maxSz = sz2;  }   virtual void reduce() = 0; protected:  POP* ppop1;  POP* ppop2;  int pop1_maxSz;   // population 1 allowed size.  int pop2_maxSz;   // population 2 allowed size.};class ClusteringReducer : public Reducer{ public:  MOEADefineIdentity("ClusteringReducer", "cR", 501);  ClusteringReducer(int chunkSize = 100);  ~ClusteringReducer() {delete[] clusters;delete[] clusterList;delete[] selectedSolutions; }  virtual void reduce() {     if(ppop1 && ppop1->currentSize() > pop1_maxSz)       reduce(*ppop1, pop1_maxSz);     if(ppop2 && ppop2->currentSize() > pop2_maxSz)       reduce(*ppop2, pop2_maxSz);   } private:  void reduce(POP& pop, int maxSz); private:  double _ClusterDistance(int  cluster1, int  cluster2, const POP& pop);  void _JoinClusters(int  cluster1, int  cluster2, int&  numOfClusters);  int  _ClusterCentroid(int  cluster, const POP& pop); private:  int    N;  int    chunkSz;  int*   clusters;        int*   clusterList;     int*   selectedSolutions;  };#endif