使用new分配内存的类需要自己定义拷贝构造函数

#include<iostream>
#include<string>
#include<new>

using namespace std;
class 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=(const HasPtr &h)
    {
        auto newp=new string(*h.ps);
        delete ps;
        ps=newp;
        i=h.i;
        return *this;
    }
    ~HasPtr() {  delete ps; cout<<"destructer"<<endl;}
private:
    string *ps;
    int i;
};
int main()
{
    HasPtr h;
    HasPtr hh(h);
    hh=h;
    return 0;
}