#include <iostream>
#include <cassert>
#include <cstring>
using namespace std;

class MyString{
public:
    MyString(const char* pData = NULL);
    MyString(const MyString& other);
    ~MyString();
    MyString& MyString::operator= (const MyString &str);
private:
    char* m_pData;
};

MyString::MyString(const char* pData=NULL){
    if(NULL == pData){
        m_pData = new char[1];
        *m_pData = '\0';
    } else {
        m_pData = new char[strlen(pData)+1];
        strcpy(m_pData, pData);
    }
}

MyString::MyString(const MyString& other){
    m_pData = new char[strlen(other.m_pData)+1];
    strcpy(m_pData, other.m_pData);
}

MyString::~MyString(){
    delete [] m_pData;
}

MyString& MyString::operator= (const MyString &str){
    if(this == &str)
        return *this;
    delete m_pData;//
    m_pData = NULL;
    m_pData = new char[strlen(str.m_pData)+1];
    strcpy(m_pData, str.m_pData);
    return *this;
}