#include<iostream>#include<string>#include<new>using namespace std;class HasPtr{public:    HasPtr(const string &s=string()):ps(new string(s)),i(0),use(new size_t(1)) {cout<<"constructer"<<endl;}    HasPtr(const HasPtr &h):i(h.i)    {        cout<<"copy constructer"<<endl;        ps=h.ps;        ++*h.use;        use=h.use;    }    HasPtr& operator=(const HasPtr &h)    {        ++*h.use;        //将原来分配的内存空间删除        while(--*use==0)        {            delete ps;            delete use;        }        //指向新的内存空间        ps=h.ps;        i=h.i;        use=h.use;        return *this;    }    //如果在赋值操作中删除了左边对象的内存空间，则此处调用析构函数时将不再删除内存空间，但是该对象还是会被析构    ~HasPtr()    {        if(--*use==0)        {            delete ps;            delete use;        }        cout<<"destructer"<<endl;    }private:    string *ps;    int i;    size_t *use;};int main(){    HasPtr h;    HasPtr hh(h);    hh=h;    return 0;}