回溯和约束编程

Question

所以我刚刚经历了一个简短的约束编程过程，第一个测试就是编写一个程序来： 目标：找到区域s.t.的颜色分配。没有 两个相邻的区域用相同的颜色着色（插入图像）

这是我提出的解决问题的cpp代码，但不幸的是它没有解决问题，我已经通过调试器运行代码但我明白了调试递归代码的挑战性。有人采取偷看并帮助我？

 #include <iostream>
    #include <vector>
    #include <string>
    #include <stdio.h>


    enum Colours{red,green,blue,yellow};
    static int count = 0;
    class Zones
    {
     int side1;
        int side2;
     int side3;
     int side4;
     Colours colour;
     public : std::vector<int> sides;
     public : std::string name;
     public :
     Zones(){}
     Zones(int s1, int s2, int s3, int s4, std::string nm)
     {
        side1=s1;
        side2=s2;
        side3=s3;
        side4=s4;
        sides.push_back(s1);
        sides.push_back(s2);
        sides.push_back(s3);
        sides.push_back(s4);
        name= nm;
    }

    Zones(int s1, int s2, int s3, std::string nm)
    {
        side1=s1;
        side2=s2;
        side3=s3;
        sides.push_back(s1);
        sides.push_back(s2);
        sides.push_back(s3);
        name= nm;
    }

     void setZoneColour(Colours colour)
    {
        this->colour = colour;
    }

    Colours getZoneColour()
    {
        return this->colour;
    }
   };

    void mapColouring( std::vector<Colours>colVec, std::vector<Zones> zSolVec,    std::vector<Zones> zVec);

   int main(int argc, char **argv)
   {
     Zones z1(2,3,4,5,"z1");
    Zones z2(1,3,4,5,"z2");
    Zones z3(1,2,4,"z3");
    Zones z4(1,2,3,5,"z4");
    Zones z5(1,2,4,"z5");

    std::vector<Zones> solVec;
    std::vector<Zones> zVec;
    zVec.push_back(z1);
    zVec.push_back(z2);
    zVec.push_back(z3);
    zVec.push_back(z4);
    zVec.push_back(z5);

    std::vector<Colours> shades;
    shades.push_back(red);
    shades.push_back(green);
    shades.push_back(blue);
    shades.push_back(yellow);

    mapColouring(shades,solVec,zVec);
    return 0;
   }

     void mapColouring( std::vector<Colours>colVec, std::vector<Zones> zSolVec, std::vector<Zones> zVec)
     {
      if(zSolVec.capacity() == 5)
      {
        //possible solution found, print it
        count++;
        //std::cout<<"we got here\n";

        std::cout<<std::endl<<count<<")";
        for(Zones z : zSolVec)
        {
            std::cout<<z.name<<"-"<<z.getZoneColour()<<" ";
        }
    }
    else
    {
        Zones curZone;
        if(!zVec.empty())
        {
             curZone=zVec.back();
             zVec.pop_back();
        }
        else return;

        for(Colours c : colVec)
        {
            curZone.setZoneColour(c);
            if(zSolVec.capacity()== 0)
            {
                std::vector<Zones> nzSolVec;
                nzSolVec.push_back(curZone);
                //zSolVec.push_back(curZone);
                //recurse
                mapColouring(colVec,nzSolVec,zVec);
            }
            else
            {
                //std::vector<Zones> :: iterator it;
                //Zones lastZone = zSolVec.back();

                bool sidematch = false;
                for(int i : zSolVec.back().sides)
                {
                    for(int j : curZone.sides)
                    {
                        if(i==j) sidematch = true;
                    }
                }
                if( (sidematch == true )&&  (zSolVec.back().getZoneColour() != curZone.getZoneColour()) )
                {
                    zSolVec.push_back(curZone);
                    //recurse
                    mapColouring(colVec,zSolVec,zVec);

                }
                else if(sidematch == false && (zSolVec.back().name != curZone.name) )
                {
                    zSolVec.push_back(curZone);
                    //recurse
                    mapColouring(colVec,zSolVec,zVec);
                }
                else if((sidematch == true) && (zSolVec.back().getZoneColour() == curZone.getZoneColour()))
                {
                    //branch end
                    return ;
                }
            }
        }
    }
}