7.26学生管理系统

//菜单
void menu(){

	printf("\t\t\t\t***************************************************\n");
	printf("\t\t\t\t*\t\t学生管理系统                    *\n");
	printf("\t\t\t\t***************************************************\n");
	printf("\t\t\t\t* 1.添加学生信息                                                  *\n");
	printf("\t\t\t\t* 2.查找学生信息                                                *\n");
	printf("\t\t\t\t  3.删除学生信息                                                  *\n");
	printf("\t\t\t\t* 4.按成绩排序                                              *\n");	
	printf("\t\t\t\t*5.退出程序                                                  *\n");
	printf("\t\t\t\t***************************************************\n");
}
//添加

int addt(student *s,int id,char name[],float score)
{
	if(NULL == s)
	{
		printf("所给链表不合法\n");
		return -1;
	}
 
	student *p = nodeBuy(id,name,score);
 
	p->next = s->next;
	s->next = p;
 
	s->len++;
	printf("添加学生信息成功\n");
	return 0;


//查找
student *seek(student *S,char name[])
{
	if(NULL == s || empty(s))
	{
		printf("查找失败\n");
		return NULL;
	}
 
	student *q = s->next;
	while(strcmp(q->data->name,name))
	{
		q = q->next;
		if(q == NULL)
		{
			printf("查无此人\n");
			return NULL;
		}
	}
 
	printf("学号\t姓名\t成绩\n");
	printf("%d\t%s\t%.2f\n",q->data->id,q->data->name,q->data->score);
 
	printf("查找成功\n");
 
	return q;
}
//删除
int delet(student *s,int id)
{
	if(NULL == s || empty(s))
	{
		printf("删除失败\n");
		return -1;
	}
 
	student *q = s;
 
	
	while(q->next->data->id != id)
	{
		q = q->next;
	}
 

	student *p = q->next;
	q->next = p->next;
	free(p->data);
	p->data = NULL;
	free(p);
	p = NULL;
	s->len--;
 
	printf("删除成功\n");
}
//排序
void sort(student *s)
{
	int i,j;          //循环变量
	datatype *temp;         //交换变量
	student *p = s>next;
	student *q = s->next->next;
 
	for(i=1;i<s->len; i++)     //比较趟数
	{
	
		for(j=0;j<s->len-i; j++)  //元素  比较次数
		{
			if(p->data->id > q->data->id)       //大升小降
			{
				temp=q->data; q->data=p->data; p->data= temp;
			}
			q = q->next;
		}
		p = p->next;
		q = p->next;
	}
	printf("排序成功\n");
 
}