#include<iostream>#include<string>#include<new>#include<vector>#include<algorithm>using namespace std;class HasPtr{friend void swap(HasPtr&,HasPtr&);public:    HasPtr(const string &s=string()):ps(new string(s)),i(0){cout<<"constructer"<<endl;}    HasPtr(const HasPtr &h):i(h.i)    {        cout<<"copy constructer"<<endl;        ps=new string;        *ps=*h.ps;//只拷贝值    }    HasPtr& operator=(HasPtr h)    {        swap(*this,h);        return *this;    }    bool operator<(const HasPtr &h) const    {        return i<h.i;    }    ~HasPtr() {  delete ps; cout<<"destructer"<<endl;}private:    string *ps;    int i;};void swap(HasPtr &lhs,HasPtr &rhs){    cout<<"swap"<<endl;    using std::swap;    swap(lhs.ps,rhs.ps);    swap(lhs.i,rhs.i);}int main(){    HasPtr h;    HasPtr hh(h);    hh=h;    swap(h,hh);    vector<HasPtr> vec={h,hh};    sort(vec.begin(),vec.end());    return 0;}