C++析构函数的调用与内存的释放先后顺序

	结论：首先调用析构函数，然后释放成员变量的内存。

#include <iostream>
#include <string>
using namespace std;

int num = 0;

class Student{
public:
    ~Student(){
        cout << num++ << endl;
        cout << "~Student() is invoked!" << endl;
    }
private:
    string name;
    int age;
};

class School{
public:
    School()
        :ps(new Student())
    {
        
    }
    ~School(){
        delete ps;
        cout << "~School() is invoked!" << endl;
    }
    
private:
    Student s; // 定义在前面，却是在delete ps之后释放的内存
    Student* ps;// 定义在后面，却是在释放s内存之前释放堆中的内存
    int number;
};

int main()
{
    School school;
    return 0;
}

// 程序输出结果
0
~Student() is invoked!
~School() is invoked!
1
~Student() is invoked!