120页第四题

#include<iostream>#include<string>using namespace std;class student{public:student(int s){score=s;}void account(int j);static void sum();static void average();private:int score;static int total_score;static int count;}; void student::account(int j){score=j;total_score+=score;++count;}void student::sum(){cout<<"总人数:"<<count<<endl;cout<<"总成绩:"<<total_score<<endl;}void student::average(){int ave;ave=total_score/count;cout<<"平均分:"<<ave<<endl;}int student::total_score=0;int student::count=0;int main(){student s1(0);char sel;    do{int j;cout<<"请输入学生成绩:"<<endl;cin>>j;s1.account(j);    cout<<"是否要继续录入学生成绩?(Y/N):";    cin>>sel;}while(sel=='Y' || sel=='y' ); student::sum();student::average();return 0;}