第四章作业4.20

#include<iostream>using namespace std;class book{int qu;int price;public:int q,p;book(){qu=q;price=p;}void countbook();void showbook();int total;};void book::countbook(){total=q*p;}void book::showbook(){cout<<"qu*price的值为："<<total<<endl;}int main(){book b1[5];int n=1;for(int i=0;i<5;i++){b1[i].q=n;b1[i].p=10*b1[i].q;n++;}book *pp,*qq;qq=&b1[0];int j=1;for(pp=&b1[4];pp<=qq,j<6;pp--,j++){cout<<"第"<<j<<"个";pp->countbook();pp->showbook();}return 0;}