4.19

#include<iostream>
#include<string>
using namespace std;
class book{
public:
book(int a,int b)
{
qu=a;
price=b;
}
void show()
{
cout<<qu*price<<endl;
}

private:
int qu;
int price;
};
int main()
{
book ok1[5]={
book(1,10),
book(2,20),
book(3,30),
book(4,40),
book(5,50)
};
for(int i=0;i<5;i++)
{
ok1[i].show();
}
system("pause");
return 0;
}