设计模式-单例模式

//懒汉式单例类
class singleton
{
public:
    static singleton *getInstance()
    {
        if(instance==NULL)
            instance=new singleton();
        return instance;
    }
private:
    static singleton*instance;
    singleton(){}
    int count=1;
};
singleton * singleton::intstace=NULL;


//饿汉子单例
class singleton
{
public:
    static singleton*getInstance()
    {
        return instance;
    }
private:
    static singleton*instance;
    int count=1;
    singleton(){}
};
//每次直接实例化instnce，get方法直接返回这个实例
singleton * singleton:instance=new singleton();