构造与析构课上栗子1

#include <iostream>
using namespace std;

class Point{
public :
	Point() :x(0), y(0) { cout << "default constructor" <<x<< endl; };
	Point(int x, int y) :x(x), y(y) { cout << "myself constructor" <<x<< endl; };
	~Point() { cout << "~Point" << x<<endl; };
private:
	int x, y;
};


Point p;

Point *m() {

	Point p1(1, 2), p2(2, 3);
	static Point p3(3,4);
	Point *p4 = new Point(4, 5);
	Point *p5 = new Point(5, 6);
	delete p4;
	return p5;

}

int main()
{


	Point *ptr = m();
	m();
	delete ptr;

   return 0;

}

default constructor0
myself constructor1
myself constructor2
myself constructor3
myself constructor4
myself constructor5
~Point4
~Point2
~Point1
myself constructor1
myself constructor2
myself constructor4
myself constructor5
~Point4
~Point2
~Point1
~Point5
~Point3
~Point0

#include <iostream>
using namespace std;

class Point{
public :
	Point() :x(0), y(0) { cout << "default constructor" <<x<< endl; };
	Point(int x, int y) :x(x), y(y) { cout << "myself constructor" <<x<< endl; };
	~Point() { cout << "~Point" << x<<endl; };
private:
	int x, y;
};


Point p;

Point *m() {

	Point p1(1, 2), p2(2, 3);
	static Point p3(3,4);
	Point *p4 = new Point(4, 5);
	Point *p5 = new Point(5, 6);
	delete p4;
	return p5;

}

int main()
{


	Point *ptr = m();

	cout << "create ptr"<< endl;
	cout << "m() start" << endl;
	m();
	cout << "m() end " << endl;
	delete ptr;
	cout << "delete ptr" << endl;

   return 0;

}

default constructor0
myself constructor1
myself constructor2
myself constructor3
myself constructor4
myself constructor5
~Point4
~Point2
~Point1
create ptr
m start
myself constructor1
myself constructor2
myself constructor4
myself constructor5
~Point4
~Point2
~Point1
m() end
~Point5
delete ptr
~Point3
~Point0