#include<iostream>
#include<cstring>
#define N 60
using namespace std;

struct student //定义了一个结构体
{
    char Name[20];
    char Number[20];
    char CourseTitle[20];
    int CourseNo;
    int CreditHours;
    int mark[10];
    float score;
};
struct student stu[N];

void studentcourse()//实现任意学生数的学分积点计算
{
    int count1;
    int count2;
    float T1=0,T2=0;float T3;
    cout<<"请输入学生的个数"<<endl;
    cin>>count2;
    cout<<"请输入科目的个数"<<endl;
    cin>>count1;
    for( int j = 0;j < count1;j ++)
        {
            cout<<"请输入第"<<j+1<<"课课程名:"<<endl;
            cin>>stu[j].CourseTitle;
            cout<<"请输入第"<<j+1<<"课课程号:"<<endl;
            cin>>stu[j].CourseNo;
            cout<<"请输入第"<<j+1<<"课课程的学分数:"<<endl;
            cin>>stu[j].CreditHours;
        }
    cout<<"~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~"<<endl;
    for(j=0;j<count2;j++)
    {
        cout<<"请输入第"<<j+1<<"个学生的姓名"<<endl;
        cin>>stu[j].Name;
        cout<<"请输入第"<<j+1<<"个学生的学号"<<endl;
        cin>>stu[j].Number;   
        cout<<endl;
        for(int i=0;i<count1;i++)
        {
            cout<<"请输入该生"<<stu[i].CourseTitle<<"的成绩：";
            cin>>stu[j].mark[i];
        }
        cout<<endl;
        for( i =0; i < count1; i++)
        {
            T1 += (stu[j].mark[i]-50)*stu[i].CreditHours/10;
            T2 +=stu[i].CreditHours;
        }
        stu[j].score = T1/T2;
    }   
    cout<<"\tName\tNumber\t";
    for(int i = 0; i < count1; i++)
    {
        cout<<stu[i].CourseTitle<<"\t";
    }
    cout<<"score"<<endl;
    for( j = 0; j < count2; j++)
    {
        cout<<"\t"<<stu[j].Name<<"\t"<<stu[j].Number<<"\t";
        for(int i = 0; i < count1; i++)
        {
            cout<<stu[j].mark[i]<<"\t";
        }
        cout<<stu[j].score<<endl;
    }
}

void Sort()// 用来按学分积点的大小来排序
{
    int i,j;
    float temp;
    for (i=0;i<n;i++)
    {
        for (j=1;j<n-i;j++)
        {
            if ((stu[j-1].score -stu[j].score)>0)
            {
                temp=stu[j-1].score;
                stu[j-1].score=stu[j].score;
                stu[j].score=temp;
            }
        }
    }
    for(i=0;i<n;i++){cout<<stu[i].score<<endl;}
}

void menu()
{
    cout<<"*****************************学分积点计算系统*****************************"<<endl<<endl<<endl;
    cout<<"  \t\t "<<"1.任意学生数的学分计算"<<"\t\t"<<"2.读取学生学分积点信息"<<endl<<endl;
    cout<<"  \t\t "<<"3.保存学生学分积点信息"<<"\t\t"<<"4.返回主菜单"<<endl<<endl;
    cout<<"请输入你要进行的操作:"<<endl;
}
void main()
{
    int m=0,n;
    while(m==0)
    {
        menu();
        cin>>n;
        switch(n)
        {
        case 1:studentcourse();break;
        case 2:coursecourse();break;
        case 3:Sort();break;
        case 4:m=1;break;
        }
    }
        
}
想通过文件的保存和读写，在计算完学分积点后，把信息保存下来，然后在主函数中直接调用sort()函数来排序，可是ofstream函数不明白怎么用在这个程序上，谁能帮我把文件的保存和读写加上，不胜感激！