C++设计模式之享元模式

     {
         if (x < other.x)
         {
             return true;
         }
         else if (x == other.x)
         {
             return y < other.y;
         }
 
         return false;
     }
}POINT;
 
typedef enum PieceColorTag
{
    BLACK,
    WHITE
}PIECECOLOR;
 
class CPiece
{
public:
    CPiece(PIECECOLOR color) : m_color(color){}
    PIECECOLOR GetColor() { return m_color; }
 
    // Set the external state
    void SetPoint(POINT point) { m_point = point; }
    POINT GetPoint() { return m_point; }
 
protected:
    // Internal state
    PIECECOLOR m_color;
 
    // external state
    POINT m_point;
};
 
class CGomoku : public CPiece
{
public:
    CGomoku(PIECECOLOR color) : CPiece(color){}
};
 
class CPieceFactory
{
public:
    CPiece *GetPiece(PIECECOLOR color)
    {
        CPiece *pPiece = NULL;
        if (m_vecPiece.empty())
        {
            pPiece = new CGomoku(color);
            m_vecPiece.push_back(pPiece);
        }
        else
        {
            bool bFound = false; // 非常感谢fireace指出的问题
            for (vector<CPiece *>::iterator it = m_vecPiece.begin(); it != m_vecPiece.end(); ++it)
            {
                if ((*it)->GetColor() == color)
                {
                    bFound = true;