链表操作

#include<stdio.h>
#include<stdlib.h>
//建立动态单向链表，结点类型；
typedef struct student{
        int no;
        int score;
        struct student *next;
        };
//创建一个链表
struct student *head;
 struct student *creat()
 {
     struct student *p,*q;
     int n, i;
     printf("how many :");
     scanf("%d",&n);
     for(i=0;i<n;i++)
     {
        p=(struct student*)malloc(sizeof(struct student));
        printf("NO :");  scanf("%d",&p->no);
        printf("Score :"); scanf("%d",&p->score);
        if(i==0)  head = p;
        else q->next=p;
        q=p;
     }
     p->next=NULL;
     return (head);
 }
//输出由表头指针head指向的链表
void print(struct student *head)
{
    struct student *p;
    p=head;
    while(p!=NULL)
    {
       printf("%d  %d/n",p->no,p->score);
       p=p->next;              
    } 
}
//函数find由表头指针head指向链表中查找学号等于n的结点
void find(struct student *head)
{
    int n;
    struct student *p;
    printf("enter NO :");
    scanf("%d",&n);
    p=head;
    while(p!=NULL && p->no!=n)
    p=p->next;
    if(p!=NULL) printf("%d %d /n",p->no,p->score);
    else printf(" not find %d student/n",n);
}
//以下函数insert用于有表头指针head指向链表中的第i个结点之后插入一个结点p
 struct student *insert(struct student *head)
 {
    int i,j;
    struct student *p,*q;
    printf("第 i 个结点 ：");
    scanf("%d",&i);
    p=(struct student*)malloc(sizeof(struct student));// fenpeiyigekongjian gei p 指针
    printf("NO :"); scanf("%d",&p->no);//
    printf("Score :"); scanf("%d",&p->score);//建了个新结点
    if(i==0)
    {
    p->next=head;
    head=p;      
    }
    else
    {
      q=head;
      for(j=1;j<i;j++)  q=q->next;//找到第i个结点，让q指向
      if(q!=NULL)
      {
          p->next=q->next;
          q->next=p;
      }
      else printf("i too biger/n");
    }
    return (head);
 }
//以下delete函数用于表头指针head指向的链表中删除第 i个结点
struct student *delet(struct student *head)
{
       int i,j;
    struct student *p,*q;
    printf("enter i (i>0) :");
    scanf("%d",&i);
    if(i==1)
    {
     p=head;
     head=head->next;
     free(p);
    }      
    else
    {
        q=head;
        for(j=1;j<i-1;j++) q=q->next;
        if(q!=NULL)
        {
          p=q->next;
          q->next=p->next;
          free(p);        
        }
    else printf("i too biger/n");
    }
    return (head);
}
 //以下由flist函数释放有表头head指向的链表
 void flist(struct student *head)
 {
  struct student *p;
  while(head !=NULL)
  {
    p=head;
    head=head->next;
    free(p);
  }    
  printf("nothing/n");
 }
int main()
{
  struct student *head;
  head=creat();
  print(head);
  find(head);
  head=insert(head);
  print(head);
  head=delet(head);
  print(head);
  flist(head);
   
  system("pause");
}