c++基本语法---拷贝构造函数

#include 
using namespace std;

class Line{
	public:
	int getLength();
	Line(int len);
	Line(const Line &obj);
	~Line();
	
	private:
	int *ptr;
	
};

Line::Line(int len){
	cout << "Line 构造函数调用" << endl;
	ptr = new int;
	*ptr = len;
}

Line::Line(const Line &obj){
	cout << "Line的拷贝构造函数调用" << endl;
	ptr = new int;
	*ptr = *obj.ptr;
	//ptr = obj.ptr;
}

Line::~Line(){
	cout << "Line的析构函数调用" << endl;
	delete ptr;
}

int Line::getLength(){
	return *ptr;
}
void display(Line obj){
	cout << "Line大小:" << obj.getLength() << endl ; 
}

int main()
{	
	Line line(10);
	display(line);
    return 0;
}