#include<iostream>
using namespace std;
class book
{
public:
book(){cout<<"first"<<"\n"<<endl;}
book(char* a, double p = 5.0);
void display();
private:
double price;
char * title;
};
book::book(char* a, double p) //在定义函数的时候可以不指定默认参数
{
cout<<"second"<<"\n"<<endl;
title = a;
price = p;
}
void book::display()
{
cout<<"The price of "<<title<<" is $"<<price<<endl;
}
int main()
{
book Three_kiongdom;
book Harry("Harry Potter", 49.9);
Harry.display();
book Gone("Gone with the Wind");
Gone.display();
return 0;
}
first
second
The price of Harry Potter is $49.9
second
The price of Gone with the Wind is $5
Process finished with exit code 0