#include<iostream.h>
#include<string.h>
#include<fstream.h>
class stu
{
	char name[20];
	double math,VC,english,average,sum;
public:
	stu(){}
	stu(char n[20],double V,double eng)
	{
		strcpy(name,n);
		math=ma;
		VC=V;
		english=eng;
	}
	double getsum()
	{
		sum=VC+english+math;
		return sum;
	}
	double getaver()
	{
		average=getsum()/3;
		return average;
	}
	friend void main();
}
void main()
{
	cout<<"學(xué)生成績管理系統(tǒng)."<<endl;
	cout<<"請選擇您需要的操作!"<<endl;
	cout<<"操作:"<<endl;
	cout<<"(0)數(shù)據(jù)錄入"<<endl;
	cout<<"(1)增加人員"<<endl;
	cout<<"(2)刪除人員"<<endl;
	cout<<"(3)修改數(shù)據(jù)"<<endl;
	cout<<"查詢:"<<endl;
	cout<<"(4)按總成績查詢"<<endl;
	cout<<"(5)按姓名查詢"<<endl;
	cout<<"(6)輸出所有學(xué)生數(shù)據(jù)"<<endl;
	cout<<"成績名詞"<<endl;
	cout<<"(7)按總分查詢排名"<<endl;
	cout<<"(8)按VC查詢排名"<<endl;
	cout<<"(9)按數(shù)學(xué)查詢排名"<<endl;
	cout<<"(y)按英語查詢排名"<<endl;
	cout<<"選擇相操作請輸入相對的括號里的數(shù)字!"<<endl;
	char p;char w;
	stu *s[50];
	ofstream *file[50];
	int i=0;
	int j=0;
	bool flag2=0;
	do
	{
		cin>>p;
		if((p>='o'&&p<='10'))
			flag2=1;
		else
			cout<<"指令錯誤!請重新輸入:"<<endl;
	}while(flag2=0);
	do
	{
		switch(p)
		{
			case'0';
			{
				char name[20];
				double math,VC,english;
				do
				{
					cout<<"請輸入姓名"<<endl;
					cin>>name;
					cout<<"請輸入數(shù)學(xué)成績:"<<endl;
					cin>>math;
					cout<<"請輸入VC成績:"<<endl;
					cin>>VC;
					cout<<"請輸入英語成績:"<<endl;
					cin>>english;
					file[j]=new ofstream("f1",ios::ate);
					*file[j]<<"姓名"<<name<<"數(shù)學(xué)成績"<<math<<"VC成績"<<VC<<"英語成績"<<english<<endl;
					j++;
					s[i]=new stu(name,mtah,VC,english);
					i++;
					cout<<"數(shù)據(jù)錄入成功,想繼續(xù)錄入嗎?(y/n)"<<endl;
					cin>>c;
					flag2=0;
					do
					{
						int flag=0;
						cout<<"請輸入你要查詢的學(xué)生的姓名"<<endl;
						cin>>n;
						for(int j=0;j<i;j++)
						{
							if(strcmp(n,(*s[j].name)==0)
							{
								flag=1;
								cout<<"您要查詢的學(xué)生是:"<<(*s[j]).name<<endl;
								cout<<(*s[j].name<<"的總成績是"<<(*s[j]).getsum()<<endl<<"平均成績是:"
									<<(*s[j].getaver()<<endl;
							}
						}
						if(flag=0)
							cout<<"對不起,沒有您要查詢的學(xué)生!"<<endl;
						cout<<"您想繼續(xù)查詢嗎?(y/n)"<<endl;
						if(c!='y'&&c!='n')
						{
							cout<<"指令錯誤!請重新輸入!"<<endl;
							cin>>c;
						}
					}
					while(c=='y');
					break;
				}
		case'1':
				{
					char name[20];double math,VC,english;
					char c;
					do
					{
						cout<<"請輸入您要增加的學(xué)生的名字:"<<endl;
						cin>>name;
						cout<<"請輸入數(shù)學(xué)成績:"<<endl;
						cin>>math;
						cout<<"請輸入VC成績:"<<endl;
						cin>>VC;
						cout<<"請輸入英語成績:"<<endl;
						cin>>english;
						file[j]=new ofstream("d:\\document",ios::ate);
						*file[j]<<"姓名"<<name<<"數(shù)學(xué)成績"<<math<<"VC成績"<<VC<<"英語成績"
	<<english<<endl;
						s[i]=new stu(name,math,VC,english);
						i++;
						cout<<"數(shù)據(jù)錄入成功,想繼續(xù)錄入嗎?(y/n)"<<endl;
						cin>>c;
						if(c!='y'&&c!='n')
						{
							cout<<"指令錯誤!請重新輸入"<<endl;
							cin>>c;
						}
					}
					while(c=='y');
					break;
				}
		case'2':
			{
				char name[20];bool flag3=0;char c;
				do
				{
					cout<<"請輸入您要刪除的學(xué)生的名字:"<<endl;
					cin>>name;
					for(int h=0;h<i;h++)
					{
						if(strcmp(name,s[h]->name)==0)
						{
							flag3=1;
							i--;
							do
							{
								s[h]=s[h=1];
								h++;
							}
							while(h<=i);
						}
					}
					if(flag3==0)
						cout<<"您要刪除的對象不存在!請檢查輸入的正確性!";
					cout<<"要繼續(xù)嗎?(y/n)"<<endl;
					cin>>c;
					if(c!='y'&&c!='n')
					{
						cout<<"指令錯誤!請重新輸入!"<<endl;
						cin>>c;
					}
				}
				while(c=='y');
				break;
			}
		case'3':
			{
				do
				{
					if(c!='y'&&c!='n')
					{
						cout<<"指令錯誤!請重新輸入!"<<endl;
						cin>>c;
					}
					else
						flag2=1;
				}while(flag2=0);
			}while(c=='y');
			break;
			}
			case'4':
				{
					double t;char c;
					do
					{
						int flag=0;
						cout<<"請輸入你要查詢的學(xué)生的成績"<<endl;
						cin>>t;
						for(int q=0;q<i;q++)
						{
							if(s[q]->getsum()==t)
							{
								flag1=1;
								cout<<"您要查詢的學(xué)生是:"<<(*s[q]).name<<endl;
							}
						}
						if(flag==0)
						cout<<"對不起!您要查詢的學(xué)生不存在!"<<endl;
						cout<<"您想繼續(xù)查詢嗎?(y/n)"<<endl;
						cin>>c;
						if(c!='y'&&c!="n")
						{
							cout<<"指令錯誤!請重新輸入!"<<endl;
							cin>>c;
						}
					}while(c=='y')
						break;
				}
			case'5':
				{
					char n[20];int j=0;char c;
					char name[20];double mat,chin,eng;flag2=0;
					char c;
					do
					{
						cout<<"請輸入您要修改的學(xué)生的名字:"<<endl;
						cin<<name;
						for(int h=0;h,i;h++)
						{
							if(strcmp(name,s[h]->name==0)
							{
								flag2=1;
								cout<<"請輸入新學(xué)生的數(shù)學(xué)成績:"<<endl;
								cin>>mat;
								cout<<"請輸入新學(xué)生的VC成績:"<<endl;
								cin>>chin;
								cout<<"請輸入新學(xué)生的英語成績:"<<endl;
								cin>>eng;
								s[h]->eng;
								s[h]->VC=chin;
								s[h]->math=mat;
								s[h]->english=eng;
								cout<<"數(shù)據(jù)修改成功!";
							}
						}
						if(flag2=0)
						{
							cout<<"您要修改的學(xué)生不存在!請檢查重新輸入!"<<endl;
						}
						cout<<"想繼續(xù)修改嗎(y/n)"<<endl;
						cin>>c;
						if(c!="y"&&c!="n")
						{
							cout<<"指令錯誤!請重新輸入!"<<endl;
							cin>>c;
						}
					}while(c=='y');
					break;
				}
			case'6':
				{
					cout<<"本系統(tǒng)所有學(xué)生數(shù)據(jù)如下:"<<endl;
					for(int k=0;k<i;k++)
					{
						cout<<k+1<<" "<<"姓名:"<<" "<<s[k]->name<<
							"VC:"<<" "<<s[k]->VC<<"數(shù)學(xué):"<<" "<<s[k]->math<<"英語:"
							<<" "<<s[k]->english<<"總分:"<<" "<<(*s[k]).getsum()
							<<"平均分:"<<" "<<(*s[k]).getaver()<<endl;
					}
					break;
				}
			case'7':
				{
					int t;stu b;
					cout<<"本系統(tǒng)所有學(xué)生排名如下:"<<endl;
					for(int x=0;x<i-1;x++)
					{
						t=x;
						for(int y=x+1;y<i;y++)
						{
							if((s[t]->getsum())<(s[y]->getsum()))
								t=y;
							if(t!=x)
							{
								b=*s[x];
								*s[x]=*s[t];
								*s[t]=b;
							}
						}
					}
					if(i==0)
						cout<<"管理系統(tǒng)中沒有錄入數(shù)據(jù)或者數(shù)據(jù)已經(jīng)被刪除!";
					for(int k=0;k<i;k++)
					{
						cout<<k+1<<" "<<"姓名:"<<" "<<s[k]->name<<"VC:"
							<<" "<<s[k]->VC<<"數(shù)學(xué):"<<" "<<s[k]->math
							<<"英語:"<<" "<<s[k]->english<<"總分:"<<" "
							<<s[k]->getsum()<<"平均分:"<<" "<<s[k]->getaver()<<endl;
					}
					break;
				}
			case'8':
				{
					int t;stu b;
					cout<<"本系統(tǒng)所有學(xué)生語文排名如下:"<<endl;
					for(int x=0;x<i-1;x++)
					{
						t=x;
						for(int y=x+1;y<i;y++)
						{
							if((s[t]->VC)<(s[y]->VC))
								t=y;
							if(t!=x)
							{
								b=*s[t];
								*s[t]=*s[x];
								*s[x]=b;
							}
						}
					}
					if(i=o)
						cout<<"管理系統(tǒng)中沒有錄入數(shù)據(jù)或者數(shù)據(jù)已經(jīng)被刪除!";
					for(int k=0;k<i;k++)
					{
						cout<<k+1<<" "<<"姓名:"<<" "<<s[k]->name<<"VC:"
							<<" "<<s[k]->VC<<"數(shù)學(xué):"<<" "<<s[k]->math
							<<"英語:"<<" "<<s[k]->english<<"總分:"<<
							" "<<s[k]->getsum<<"平均分:"<<" "<<s[k]->getaver
							<<endl;
					}
					break;
				}
			case'9':
				{
					int t;stu b;
					cout<<"本系統(tǒng)所有學(xué)生數(shù)學(xué)排名如下:"<<endl;
					for(int x=0;x<i-1;x++)
					{
						t=x;
						for(int y=x+1;y<i;y++)
						{
							if((s[t]->math)<s[y]->math)
								t=y;
							if(t!=x)
								b=*s[t];
							*s[t]=*s[x];
							*s[x]=b;
						}
					}
				}
				if(i=0)
					cout<<"管理系統(tǒng)中沒有錄入數(shù)據(jù)或者數(shù)據(jù)已經(jīng)被刪除!";
				for(int k;k<i;k++)
				{
                   cout<<k+1<<" "<<"姓名:"<<" "<<s[k]->name<<"VC:"
			       <<" "<<s[k]->VC<<"數(shù)學(xué):"<<" "<<s[k]->math
				   <<"英語:"<<" "<<s[k]->english<<"總分:"<<" "
				   <<s[k]->getsum()<<"平均分:"<<" "<<s[k]->getaver()<<endl;
				}
				break;
		}
		case
	}
}