C++---深拷貝

#include <iostream>
#include <string>

using namespace std;

class Test
{
    int* m_pointer;
public:
    Test()
    {
        m_pointer = NULL;
    }
    Test(int i)
    {
        m_pointer = new int(i);
    }
    Test(const Test& obj)
    {
        m_pointer = new int(*obj.m_pointer);
    }
    // Test& operator = (const Test& obj)
    // {
    //     if( this != &obj )
    //     {
    //         delete m_pointer;
    //         m_pointer = new int(*obj.m_pointer);
    //     }
        
    //     return *this;
    // }
    Test& operator = (const Test& obj)
    {
        if( this != &obj)
        {
            delete m_pointer;
            m_pointer = new int(*obj.m_pointer);
        }
        return *this;
    }
    void print()
    {
        
        cout << "m_pointer = " << hex << m_pointer << endl;
    }
    ~Test()
    {
        delete m_pointer;
    }
};

int main()
{
    Test t1 = 1;
    Test t2;
    
    t2 = t1;
    
    t1.print();
    t2.print();
    
    return 0;
}