第4题

#include<iostream>#include<string>using namespace std;class student{public:void account();static void account_count_sum_average();student(string name1,float score1);private:string name;static float totai_score();static int count;static float sum;static float average;float score;};student::student(string name1,float score1){name=name1;score=score1;++count;sum+=score;average=sum/count;}void student::account(){cout<<"姓名："<<name<<endl;cout<<"成绩："<<score<<endl;} void student::account_count_sum_average(){cout<<"学生人数："<<count<<endl;cout<<"累加成绩"<<sum<<endl;cout<<"平均成绩："<<average<<endl;}int student::count=0;float student::sum=0.0;float student::average=0.0;int main(){student stu1("dlh",100);stu1.account();student::account_count_sum_average();student stu2("wy",90);stu2.account();student::account_count_sum_average();return 0;}