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#include 
   
    #include 
    
     #include 
     
      #include 
      
       class CMyString {private:	char * buf;	int len;private:	void copy(const char* s) {		buf = new char[len+1];		memcpy(buf, s, len);		buf[len] = '\0';	}public:	CMyString() {		std::cout << "构造函数" << std::endl;		buf = nullptr;		len = 0;	}	CMyString(const char* str = nullptr) {		if (str == nullptr) {			std::cout << "构造函数" << std::endl;			buf = nullptr;			len = 0;		}		else {			std::cout << "构造函数" << str << std::endl;			len = strlen(str);			copy(str);		}	}	CMyString(const CMyString& str) {		std::cout << "拷贝构造函数" << str.buf << std::endl;		len = str.len;		copy(str.buf);			}	CMyString(CMyString&& str) {		std::cout << "移动构造函数" << str.buf << std::endl;		//也可以直接使用std::move		len = str.len;		buf = str.buf;				str.len = 0;		str.buf = nullptr;	}	CMyString& operator=(const CMyString& str) {		std::cout << "拷贝赋值函数" << str.buf << std::endl;		if (&str != this) {			if (buf != nullptr) {				delete[] buf;				buf = nullptr;			}			len = str.len;			copy(str.buf);		}		return *this;	}		CMyString& operator=(CMyString&& str) {		std::cout << "移动赋值函数" << str.buf << std::endl;		if (this != &str) {			if (buf != nullptr) {				delete[] buf;				buf = nullptr;			}			len = str.len;			buf = str.buf;			str.len = 0;			str.buf = nullptr;		}		return *this;	}	~CMyString() {		if (buf == nullptr)		{			std::cout << "析构函数" << std::endl;		}		else		{			std::cout << "析构函数" << buf << std::endl;			delete[] buf;			buf = nullptr;		}	}	void print() {		if (buf != nullptr)			std::cout << buf << std::endl;		else			std::cout << "buf is null" << std::endl;	}	};void func1(CMyString str) {	}CMyString func2() {	CMyString s("34");	return s;}void test0() {	CMyString s1("12");	func1(s1); //对象str尚未初始化，会调用拷贝构造函数	CMyString s2 = func2(); // 对象s2尚未初始化，会产生临时对象，调用移动构造函数	CMyString s3 = "56";	s3 = s1; //对象s3已初始化，会调用拷贝赋值函数}void test1() {	CMyString s4 = "78";	std::vector
       
         v1;	//v1.push_back(s4);	v1.push_back(std::move(s4)); // 对象尚未初始化，会调用移动构造函数	std::cout << "开始输出v1\n";	for (auto& str : v1)		str.print();	std::vector
        
          v2; v2 = std::move(v1); std::cout << "开始输出v1\n"; for (auto& str : v1) str.print(); std::cout << "开始输出v2\n"; for (auto& str : v2) str.print();}void test2() { CMyString s5 = "9"; s5 = func2(); // 对象s5已初始化， 会产生临时对象，调用移动赋值函数}int main(void){ std::cout << "begin test0()" << std::endl; test0(); std::cout << std::endl; std::cout << "begin test1()" << std::endl; test1(); std::cout << std::endl; std::cout << "begin test2()" << std::endl; test2(); return 0;}