#include<vector>
#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<algorithm>
#include<cstring>
#include<string>
using namespace std;


typedef struct Student{
 int ID; /*學(xué)生學(xué)號(hào)*/
 char name[15]; /*學(xué)生姓名*/ 
 vector<double> subject; /*因未知課程數(shù)量，所以課程數(shù)量采用動(dòng)態(tài)數(shù)組vector*/
 double sum; /*學(xué)生各科成績(jī)總分*/
}Student;


struct Rule{ /*排序規(guī)則*/ 
 bool operator()(const Student &stu1,const Student &stu2)const
 {
 if(stu1.sum!=stu2.sum) /*總分不相等按照總分從大到小排序*/ 
 return stu1.sum>stu2.sum;
 return stu1.ID>stu2.ID; /*總分相等按照學(xué)號(hào)從大到小排序*/ 
 }
};


int N,M,i,j; /*N為學(xué)生人數(shù)，M為課程數(shù)量*/
double score; /*臨時(shí)變量*/
Student temp; /*臨時(shí)變量*/
vector<Student> Stu; /*本課設(shè)采用動(dòng)態(tài)數(shù)組vector，防止浪費(fèi)內(nèi)存空間*/
bool condition=true; /*系統(tǒng)運(yùn)行狀態(tài)*/
char choice; /*用于輸入來(lái)選擇功能*/


/*---------------------------------------------a.成績(jī)錄入---------------------------------------------*/
void InsertScore(){
 cout<<"請(qǐng)輸入班級(jí)學(xué)生數(shù)量和課程數(shù)量：";
 cin>>N>>M;
 cout<<endl<<"現(xiàn)在請(qǐng)依次輸入每個(gè)學(xué)生的學(xué)號(hào)、姓名和"<<M<<"門課程的成績(jī)："<<endl<<endl;
 for(i=0;i<N;++i){
 cin>>temp.ID>>temp.name;
 for(j=0;j<M;++j){
 cin>>score;
 temp.subject.push_back(score);
 }
 Stu.push_back(temp);
 /*------------------------------這一行很重要------------------------------*/
 /*------------------------------這一行很重要------------------------------*/
 vector<double>().swap(temp.subject);
 /*------------------------------這一行很重要------------------------------*/
 /*------------------------------這一行很重要------------------------------*/ 
 }
 cout<<endl<<"成績(jī)錄入成功！"<<endl; 
}


/*---------------------------------------------b.成績(jī)顯示---------------------------------------------*/
void ShowScore(){
 cout<<"學(xué)號(hào)\t\t"<<"姓名\t\t";
 for(i=0;i<M;++i)
 cout<<"課程"<<i+1<<"\t";
 cout<<endl;
 for(i=0;i<N;++i){
 cout<<Stu[i].ID<<"\t"<<Stu[i].name<<"\t";
 for(int j=0;j<M;++j)
 cout<<Stu[i].subject[j]<<"\t";
 cout<<endl;
 }
}


/*---------------------------------------------c.成績(jī)保存---------------------------------------------*/
void SaveScore(){
 FILE *fp;
 if((fp=fopen("stu.dat","wb"))==NULL){
 cout<<"文件打開(kāi)錯(cuò)誤";
 return; 
 }
 for(i=0;i<N;++i){
 if(fwrite(&Stu[i],sizeof(Student),1,fp)!=1)
 cout<<"寫入錯(cuò)誤！"<<endl; 
 }
 fclose(fp);
 cout<<"成績(jī)保存成功！"<<endl; 
}


/*---------------------------------------------d.成績(jī)排序---------------------------------------------*/
void SortScore(){
 for(i=0;i<N;++i){ /*計(jì)算每個(gè)人的總成績(jī)*/
 Stu[i].sum=0;
 for(j=0;j<M;++j)
 Stu[i].sum+=Stu[i].subject[j];
 }
 sort(Stu.begin(),Stu.end(),Rule()); /*使用排序函數(shù)排序*/
 cout<<"成績(jī)排序成功！"<<endl;
}


/*---------------------------------------------e.成績(jī)修改---------------------------------------------*/
void ModifyScore(){
 string password;
 int id,no;
 cout<<"請(qǐng)輸入密碼開(kāi)啟成績(jī)修改權(quán)限：";
 cin>>password;
 
 /*------------------------------密碼輸入錯(cuò)誤------------------------------*/
 while(password!="GUXUNMEI"){
 cout<<endl<<"密碼錯(cuò)誤，請(qǐng)重新輸入，若輸入Q則中止進(jìn)入成績(jī)修改功能：";
 cin>>password;
 if(password=="Q")
 return;
 }
 
 /*------------------------------密碼輸入正確------------------------------*/
 cout<<endl<<"成功進(jìn)入成績(jī)修改功能，若學(xué)號(hào)輸入-1則退出成績(jī)修改功能!"<<endl; 
 while(1){
 cout<<endl<<"請(qǐng)輸入需要修改成績(jī)的學(xué)生的學(xué)號(hào),第幾門課程以及修改后的分?jǐn)?shù):";
 cin>>id;
 if(id==-1){
 cout<<endl<<"已成功退出成績(jī)修改功能！"<<endl;
 return; 
 }
 cin>>no>>score;
 if(no>M){ /*課程不存在*/ 
 cout<<endl<<"不存在此課程！"<<endl;
 continue;
 }
 for(i=0;i<N;++i){
 if(Stu[i].ID==id){
 Stu[i].subject[no-1]=score;
 break;
 }
 }
 if(i==N){  /*學(xué)生不存在*/ 
 cout<<endl<<"不存在此學(xué)生！"<<endl;
 continue; 
 }
 cout<<endl<<"修改成功！"<<endl; 
 }
}


/*---------------------------------------------f.成績(jī)統(tǒng)計(jì)---------------------------------------------*/
void CountScore(){
 int maxn[M],count[M];
 double k,average[M]; 
 memset(maxn,0,sizeof(maxn));
 
 /*--------------------顯示每門課程成績(jī)最高的學(xué)生的基本信息--------------------*/ 
 for(i=0;i<N;++i){
 for(j=0;j<M;++j){
 if(Stu[i].subject[j]>Stu[i].subject[maxn[j]])
 maxn[j]=i;
 }
 }
 for(i=0;i<M;++i){
 cout<<"課程"<<i+1<<"成績(jī)最高分學(xué)生信息："<<Stu[i].ID<<"\t"<<Stu[i].name<<"\t";
 for(j=0;j<M;++j)
 cout<<Stu[i].subject[j]<<"\t";
 cout<<endl;
 }
 cout<<endl;
 
 /*---------------------------顯示每門課程的平均成績(jī)---------------------------*/
 for(j=0;j<M;++j){
 k=0;
 for(i=0;i<N;++i)
 k+=Stu[i].subject[j];
 average[j]=k/N;
 cout<<"課程"<<j+1<<"的平均成績(jī)?yōu)椋?<<average[j]<<endl; 
 }
 cout<<endl;
 
 /*---------------------顯示超過(guò)某門課程平均成績(jī)的學(xué)生人數(shù)---------------------*/
 for(j=0;j<M;++j){
 count[j]=0;
 for(i=0;i<N;++i){
 if(Stu[i].subject[j]>average[j])
 ++count[j];
 }
 cout<<"超過(guò)課程"<<j+1<<"平均成績(jī)的學(xué)生人數(shù)為："<<count[j]<<endl; 
 }
}


/*---------------------------------------------g.退出系統(tǒng)---------------------------------------------*/
void ExitSystem(){
 condition=false; /*全局變量condition控制程序運(yùn)行*/
 cout<<"已退出班級(jí)成績(jī)管理系統(tǒng)"<<endl; 
}

 
int main()
{
 while(condition){
 /*-----------------------------------系統(tǒng)菜單-----------------------------------*/
 cout<<"        "<<endl;
 cout<<"-------------------------系統(tǒng)菜單-------------------------"<<endl;
 cout<<"        "<<endl;
 cout<<"  請(qǐng)選擇系統(tǒng)功能項(xiàng)：    "<<endl;
 cout<<"    a.成績(jī)錄入   "<<endl;
 cout<<"    b.成績(jī)顯示   "<<endl;
 cout<<"    c.成績(jī)保存   "<<endl;
 cout<<"    d.成績(jī)排序   "<<endl;
 cout<<"    e.成績(jī)修改   "<<endl;
 cout<<"    f.成績(jī)統(tǒng)計(jì)   "<<endl;
 cout<<"    g.退出系統(tǒng)   "<<endl;
 cout<<"        "<<endl;
 cout<<"----------------------------------------------------------"<<endl;
 cout<<"        "<<endl;
 
 /*-----------------------------------選擇系統(tǒng)功能項(xiàng)-----------------------------------*/
 cout<<"請(qǐng)輸入選項(xiàng)：";
 cin>>choice;
 cout<<endl;
 switch(choice){
 case 'a':InsertScore(); break;
 case 'b':ShowScore(); break;
 case 'c':SaveScore(); break;
 case 'd':SortScore(); break;
 case 'e':ModifyScore(); break;
 case 'f':CountScore(); break;
 case 'g':ExitSystem(); break;
 default:cout<<"不存在此項(xiàng)功能！"<<endl;
 } 
 }
 return 0;
}