定义一个链表存放10个学生的学号、姓名、成绩，从键盘输入数据。
定义一个链表存放10个学生的学号、姓名、成绩，从键盘输入数据。
将链表的内容输出到屏幕上。
按学号进行查找、插入、删除。
将链表的内容输出到文件cx.txt
#include
#include
#define NULL 0
#define LEN sizeof(struct student)
struct student
{
long num;
charname[20];
int score;
structstudent *next;
};
int n;
struct student *creat() /*此函数返回一个指向链表头的指针*/
{
structstudent *head;
structstudent *p1,*p2;
n=0;
p1=p2=(structstudent *)malloc(LEN); /*开辟一个新单元*/
printf("请输入学号,姓名和成绩(学号为0结束)：\n");
scanf("%ld%s%d",&p1->num,p1->name,&p1->score);
//head=NULL;
while(p1->num!=0)
{
n=n+1;
if(n==1)
head=p1;
else
{
p2->next=p1;
p2=p1;
p1=(structstudent *)malloc(LEN);
scanf("%ld%s%d",&p1->num,p1->name,&p1->score);
}
}
p2->next=NULL;
return(head);
}
void print(struct student *head)//遍历函数
{
structstudent *p;
p=head;
while(p!=NULL)
{
printf("%ld%s %d\n",p->num,p->name,p->score);
p=p->next;
}
}
struct student *insert(struct student *h,inti,struct student *f)//插入函数
{
structstudent *p;
int j;
p=h;
f=(structstudent *)malloc(sizeof(struct student ));
scanf("%ld%s%d",&f->num,f->name,&f->score);
j=2;
while(j
{
p=p->next;
j++;
}
if(i==1)
{
h=f;
f->next=p;
}
else
{
f->next=p->next;
p->next=f;
}
return (h);
}
struct student *del(struct student *h,int i)//删除函数；
{
structstudent *p=h,*q;
int flag=0;
while(p->next&&p->num!=i)
{
q=p;
p=p->next;
}
if(p->num==i)
{
q->next=p->next;
printf("删除后\n");
print(h);
free(p);
flag=1;
}
if(!flag)
{
printf("查无此人\n");
}
return (h);
}
struct student *de(struct student *h,int i)//查找函数
{
structstudent *p=h;
int flag=0;
while(p!=NULL)
{
if(p->num==i)
{
printf("结果为\n");
printf("%ld%s %d\n",p->num,p->name,p->score);
flag=1;
break;
}
p=p->next;
}
if(!flag)
{
printf("查无此人\n");
}
return (h);
}
void in(struct student *head)//保存函数
{
structstudent *p;
FILE *fp;
if((fp=fopen("cx.txt","w+"))==NULL)
{
printf("Cannotopen this file!\n");
exit(0);
}
fprintf(fp,"学号 姓名 成绩\n");
p=head;
while(p!=NULL)
{
fprintf(fp,"%2ld%2s %2d\n",p->num,p->name,p->score);
p=p->next;
}
printf("已保存\n");
fclose(fp);
}
void main()
{
structstudent *list=creat() ;
intj,choice;
structstudent *f=0;
do{
printf("选择你需要的操作\n");
printf("1:删除 2:插入 3:查找 4:保存 0:退出\n");
scanf("%d",&choice);
switch(choice)
{
case1:
{
printf("请输入要删除的学号\n");
scanf("%d",&j);
list=del(list,j);
break;
}
case2:
{
printf("请输入在第几个节点前插入\n");
scanf("%d",&j);
printf("请输入插入数据\n");
list=insert(list,j,f);
printf("插入后数据\n");
print(list);
break;
}
case3:
{
printf("输入学号\n");
scanf("%d",&j);
list=de(list,j);
break;
}
case4:{
//list=de(list,j);
in(list);
break;
}
case0:break;
}
}while(choice!=0);
printf("谢谢使用\n");
}