读程序题-关于构造函数和析构函数

#include<iostream>
using namespace std;

class Base
{
public:
         Base(){ cout << "construct in Base" << endl;}
         Base (Base & b) {cout << "copy in Base" << endl;}
         ~Base(){cout << "deconstruct in Base" << endl;}
         int a;

};

class Derive: public Base
{
public:
         Derive(){cout << "construct in Derive" << endl;}
         Derive(Derive & b) {cout << "copy in Derive" << endl;}
         ~Derive(){cout << "deconstruct in Derive" << endl;}
         Derive getderive(Derive a) {return a;}
};

int main()
{
         Derive d;
         Derive a = d.getderive(d);
         return 0;
}