请帮忙看看关于链表的操作问题出在哪里了 这是谭浩强的C语言程序设计书上的
#include<iostream>using namespace std;
#define NULL 0
#define LEN sizeof(struct student)
struct student
{
long num;
float score;
struct student *next;
};
int n;
struct student *creat(void)
{
struct student *head;
struct student *p1,*p2;
n=0;
p1=p2=(struct studen *)malloc(LEN);
cin>>p1->num>>p1->score;
head=NULL;
while(p1->num!=0)
{
n=n+1;
if(n==1)
head=p1;
else
p2->next=p1;
p2=p1;
p1=(struct student*)malloc(LEN);
cin>>p1->num>>p1->score;
}
p2->next=NULL;
return (head);
}
void print(struct student *head)
{
struct student *p;
p=head;
if(head!=NULL)
do
{
cout<<p->num<<p->score<<endl;
p=p->next;
}while(p!=NULL) ;
}
struct student *del(struct student *head,long num)
{
struct student *p1,*p2;
if(head==NULL)
{
cout<<"list is null"<<endl;
}
p1=head;
while(num!=p1->num&&p1->next!=NULL)
{
p2=p1;
p1=p1->next;
}
if(p1->num==num)
{
if(p1==head)
head=p1->next;
else
p2->next=p1->next;
n=n-1;
}
else
cout<<"can't find "<<num<<endl;
return (head);
}
struct student *insert(struct student *head,struct student *stud)
{
struct student *p0,*p1,*p2;
p0=stud;
p1=head;
if(head==NULL)
{
head=p0;
p0->next=NULL;
}
else
{
while(p0->num>p1->num&&p1->next!=NULL)
{
p2=p1;
p1=p1->next;
}
if(p0->num<=p1->num)
{
if(p1==head)
{
head=p0;
}
else
{
p2->next=p0;
}
p0->next=p1;
}
else
{
p1->next=p0;
p0->next=NULL;
}
}
n=n+1;
return (head);
}
void main()
{
struct student *head,stu;
long del_num;
cout<<"input records:"<<endl;
head=creat();
print(head);
cout<<"input the deleted number:"<<endl;
cin>>del_num;
head=del(head,del_num);
print(head);
cout<<"input the inserted record:"<<endl;
cin>>stu.num>>stu.score;
head=insert(head,&stu);
print(head);
}
