学生成绩信息管理c++

-------dyh--------
#include<iostream>
#include<cstring>
using namespace std;

struct student{
	char  id[11];			//学生学号 
	char  name[10];			//学生姓名 
	char  xy[14];			//学院
	int   c;
	int   jd;
	int   sx;
	int   sm;
	
	student *next;
};


void insert_student(student *s)
{
	int i=1,n;
	cout<<"\n 请输入所添加的学生人数:";
	cin>>n;
	student *q;
	
	for(;i<=n;i++)
	{
		q=new student;
		while(s->next!=NULL)
		s=s->next;
		s->next=q;
		cout<<"c请输入第:"<<i<<endl;
		
		cout<<"c请输入学号:";
		cin>>q->id;
		cout<<endl;
		
		cout<<"c姓名:";
		cin>>q->name;
		cout<<endl;
		
		cout<<"c学院:";
		cin>>q->xy;
		cout<<endl;
		
		cout<<"cc语言:";
		cin>>q->c;
		cout<<endl;
		
		cout<<"c计算机导论:";
		cin>>q->jd;
		cout<<endl;
		
		cout<<"c数学:";
		cin>>q->sx;
		cout<<endl;
		q->sm=q->c+q->jd+q->sx;
		
		q->next=NULL;
		
		

	}
	
 } 
 
int  out_student(student *s)
 {	
	s=s->next;
	int i=1,t=0;
 	while(s!=NULL)
 	{
		cout<<"\n"<<"-----------"<<i<<"----------"<<endl;
 		cout<<"c输出第:"<<i<<endl;
		
		cout<<"c学号:"<<s->id;
		cout<<endl;
		
		cout<<"c姓名:"<<s->name;
		cout<<endl;
		
		cout<<"c学院:"<<s->xy;
		cout<<endl;
		
		cout<<"cc语言:"<<s->c;
		cout<<endl;
		
		cout<<"c计算机导论:"<<s->jd;
		cout<<endl;
		
		cout<<"c数学:"<<s->sx;
		cout<<endl;
		
		cout<<"c总分:"<<s->sm;
		cout<<endl;
		
		s=s->next;
	 	i++;
		cout<<endl;
		t++;
	 }
	 
 	return t;
 	
 }

int modify_student(student *l)
	{	int t;
			char id[10];
			cout<<"\n请输入要修改的学生学号:";
			cin>>id;
			while(l->next!=NULL)
			{
				if(strcmp(l->id,id)==0)
					break;
				l=l->next;
			}
			if(strcmp(l->id,id)==0)
			{
				cout<<"\n学号:"<<l->id;

				cout<<"\n姓名:"<<l->name;

				cout<<"\n学院:";
				cin>>l->xy;

				cout<<"\nc语言:";
				cin>>l->c;

				cout<<"\n计算机导论:";
				cin>>l->jd;

				cout<<"\n数学:";
				cin>>l->sx;
				l->sm=l->c+l->jd+l->sx;

				t=1;

			}else{
				cout<<"\n没有此学生!";
				t=0;
				
			}


		return t;
	}

int select_student(student *l)
{
		int t;
			char id[10];
			cout<<"\n请输入要查询的学生学号:";
			cin>>id;
			while(l->next!=NULL)
			{
				if(strcmp(l->id,id)==0)
					break;
				l=l->next;
			}
			if(strcmp(l->id,id)==0)
			{
				cout<<"\n学号:"<<l->id;

				cout<<"\n姓名:"<<l->name;

				cout<<"\n学院:"<<l->xy;

				cout<<"\nc语言:"<<l->c;

				cout<<"\n计算机导论:"<<l->jd;

				cout<<"\n数学:"<<l->sx;
				
				cout<<"\n总分:"<<l->sm;

				t=1;

			}else{
				cout<<"\n没有此学生!";
				t=0;
				
			}


		return t;


}

int clear_student(student *s)
{int t; 
	if(s->next!=NULL)			//判断s是否为空 
	{
		s->next=NULL;//delete[]s;
		t=1;					//清空成功 
	 } 
	 else
	 t=0;						//失败 
	
	
return t;
}

int main()
{
	student *s;
	s=new student;			//开辟空间 
	s->next=NULL;
	
	int n;
	cout<<"============c++学生成绩管理============\n";


		while(1)
		{
		cout<<"\n--------学生成绩查询设置--------";
		cout<<endl; 
		cout<<"\n----->1 、添加\n";
		cout<<"\n----->2 、修改\n";
		cout<<"\n----->3 、查学生成绩\n";
		cout<<"\n----->4 、输出学生信息\n";
		cout<<"\n----->5 、清空学生信息\n";
		cout<<"\n----->0 、退出\n";
		cout<<"\n -------------------------------";
		cout<<"请选择:";
		cin>>n;
		switch(n)
		{
			case 1:
					insert_student(s);
						cout<<"\n      添加成功...\n";
					break; 
			case 2:
					if(modify_student(s))
					{	cout<<"\n      添加成功...\n";	
						break;
					}else{
						cout<<"\n      添加失败...\n";
						break;
					}

			case 3:
					if(select_student(s))
					{
						cout<<"\n      查询完毕...";
						break;
					}else{
						cout<<"\n      查询失败...";
						break;
					}

			case 4: 
					if(out_student(s))
					{
						cout<<"\n      输出成功...";
						break;
					}else{
						cout<<"\n      输出失败...";
						break;
					}

			case 5:
					if(clear_student(s))
					{
						cout<<"\n      清空完成...";
						break;
					}else{
						cout<<"\n      清空失败...";
						break;
					}
			case 0:
				return 0;
			default : cout<<"输入错误....回车继续！";
		} 
	}
return 0;	
}