课程设计：学生管理系统(c++)

#include <iostream>
#include <string>
#include <set>
#include <fstream>
#include <cstdlib>
#include <vector>
#include <windows.h>
#include <algorithm>
using namespace std;

class score         //分数
{
public:

    int s_total;
    int s_ave;
    int s_sum;

};

class course        //课程信息
{
    public:
    int cou_id;
    string cou_name;
    int mark;           //分数

};

class student:public score          //学生信息
{
public:
    string name;
    string sex;
    int std_id;
    int s_normal;       //平时成绩
    double per;     //平时成绩所占百分比
    int m;          //该学生选课的门数
    vector<course> cour;        //该学生所选的课

};
bool operator < (const student &stu1,const student &stu2)
    {
        return stu1.std_id> stu2.std_id;
    }


class grades        //班级
{
public:
    string major;
    int cla_id;
    int peop_num;
    multiset<student> stu;

    void fread(int n);                  //对成绩的录入,n个学生
    void revise(int t_ID);              //根据学号修改学生信息
    void display(void);                 //打印班级成绩单
    void seek(int t_ID);                //查找
    void failshow(void);                //打印不及格学生名单

};
void grades::failshow()
{
    ofstream outfile("outn.dat",ios::out);
    multiset<student>::iterator iter;
    for(iter=stu.begin();iter!=stu.end();iter++)
    {
        if((*iter).s_ave<60)
            outfile<<(*iter).name<<" "<<(*iter).std_id<<" "<<endl;
    }
    outfile.close();
    cout<<"完成：输出到:./outn.dat"<<endl;

}
void grades::seek(int t_ID)             //查找学号为t_ID的学生
{
    student temstu;
    temstu.std_id=t_ID;
    multiset<student>::iterator iter=stu.find(temstu);
    if(iter!=stu.end())
    {
        cout<<"姓名: "<<(*iter).name<<"学号:"<<(*iter).std_id<<endl;
        for(int i=0;i<(*iter).m;i++)
        {
            cout<<(*iter).cour.at(i).cou_name<<": "<<(*iter).cour.at(i).mark;
        }
        cout<<"总成绩:"<<(*iter).s_sum<<"综评成绩:"<<(*iter).s_total<<endl;

    }
    else
        cout<<"找不到该学生"<<endl;

}

void grades::display(void)          //输出班级成绩单
{
    multiset<student>::iterator iter;
    ofstream outfile("out.dat",ios::out);
    if(!outfile)
    {
        cout<<"open error"<<endl;
        exit(1);
    }
    outfile<<"专业:"<<major<<"班级:"<<cla_id<<"人数"<<peop_num<<endl;
    outfile<<"姓名\t"<<"性别\t"<<"学号\t"<<"各科成绩\t"<<"总成绩\t\t"<<"综评成绩\t"<<endl;
    for(iter=stu.begin();iter!=stu.end();iter++)
    {
        outfile<<(*iter).name<<"\t"<<(*iter).sex<<"\t"<<(*iter).std_id<<" ";
        for(int i=0;i<(*iter).m;i++)
            outfile<<(*iter).cour.at(i).cou_name<<" "<<(*iter).cour.at(i).mark<<" ";
        outfile<<"\t"<<(*iter).s_sum<<"\t"<<(*iter).s_total<<"\t"<<endl;

    }
    outfile.close();
    cout<<"完成,输出到:./out.dat"<<endl;


}

void grades::fread(int n)
{
    student tem;
    course t;
    ifstream infile("in.dat",ios::in);
    if(!infile)
    {
        cout<<"open error !"<<endl;
        exit (1);
    }
    for(int i=0;i<n;i++)
    {
        infile>>tem.name>>tem.sex>>tem.std_id>>tem.per>>tem.s_normal;       //设置学生信息
        infile>>tem.m;
        tem.s_sum=0;
        for(int j=0;j<tem.m;j++)
            {
                infile>>t.cou_id>>t.cou_name>>t.mark;
                tem.s_sum+=t.mark;         //总分
                tem.cour.push_back(t);
            }

        tem.s_ave=(tem.s_sum)/tem.m;                                             //平均分
        tem.s_total=tem.s_normal*tem.per+tem.s_sum*(1-tem.per);              //总评成绩
        stu.insert(tem);

    }
    infile.close();


}
void grades::revise(int t_ID)
{
    student temstu;
    temstu.std_id=t_ID;
    temstu.s_sum=0;
    vector<course>::iterator i;
    multiset<student>::iterator iter=stu.find(temstu);
    if(iter!=stu.end())
    {
        cout<<"请输入要修改的学生信息"<<endl;
        /*for(i=(*iter).cour.begin();i!=(*iter).cour.end();i++)
        {
            cout<<(*iter).cour.at(i).cou_name<<":"<<endl;
            cin>>temstu.cour.at(i).mark;
            temstu.s_sum+=temstu.cour.at(i).mark;

        }*/
        cout<<"平时成绩"<<endl;
        cin>>temstu.s_normal;
        cout<<"平时成绩所占百分比"<<endl;
        cin>>temstu.per;
        temstu.s_ave=temstu.s_sum/temstu.m;
        temstu.s_total=temstu.s_normal*temstu.per+temstu.s_sum*(1-temstu.per);
        cout<<"姓名"<<endl;
        cin>>temstu.name;
        cout<<"性别:"<<endl;
        cin>>temstu.sex;
        stu.erase(iter);        //删除旧元素
        stu.insert(temstu);     //插入新元素
        cout<<"修改完成"<<endl;

    }
    else
        cout<<"找不到该学生"<<endl;


}

int main()
{
    system("color d0");
    int c;
    int t;
    grades cla;
    cout<<"********************************************************************************"<<endl;
    cout<<"********************************学生管理系统************************************"<<endl;
    cout<<"请输入学生人数:"<<endl;
    cin>>cla.peop_num;
    cout<<"请输入专业:"<<endl;
    cin>>cla.major;
    cout<<"请输入班级"<<endl;
    cin>>cla.cla_id;
    cla.fread(cla.peop_num);
    while(1)
    {
        system("cls");
        cout<<"********************************************************************************"<<endl;
        cout<<"********************************************************************************"<<endl;
        cout<<"                ~~~~~~~~~1_修改学生信息~~~~~~~~~"<<endl;
        cout<<"                ~~~~~~~~2_打印班级成绩单~~~~~~~~"<<endl;
        cout<<"                ~~~~~~~~3_打印个人成绩单~~~~~~~~"<<endl;
        cout<<"                ~~~~~~4_打印不及格学生名单~~~~~~"<<endl;
        cout<<"                ~~~~~~~~~~~~~~5_退出~~~~~~~~~~~~"<<endl;
        cin>>c;
        switch (c)
        {
        case 1:
            cout<<"请输入要修改的学生学号:";
            cin>>t;
            cla.revise(t);
            break;
        case 2:
            cla.display();
            break;
        case 3:
            cout<<"请输入要打印的学生学号:";
            cin>>t;
            cla.seek(t);
            break;
        case 4:
            cla.failshow();
            break;
        case 5:
            return 0;

        default:
            cout<<"输入错误！"<<endl;

        }
        system("pause");
    }



    return 0;
}