#include<malloc.h>
#include<stdio.h>
#define null 0
struct student
{
 long Number;
 char Name[20];
 long Score;
 struct student *Next;
};

int n=0;/*n为全局变量，用来计算链表的结点个数*/

/*-----------------------------------------*/
/*--------------创建结点函数Creat()--------*/
/*-----------------------------------------*/
struct student *Creat()
{

  struct student *p1;
  struct student *p2;
  struct student *head=null;
  p1=p2=(struct student *)malloc(sizeof(struct student));/*开辟一段可用内存单元*/
  printf("please input the student's Number Name and the Score:\n");
  scanf("%ld%s%ld",&p2->Number,p2->Name,&p2->Score);

  while(p2->Number!=0)
  {
      n++;

      if(n==1)            /*是否开辟的是第一个结点*/
      head=p2;
      else
      p1->Next=p2;

      p1=p2;
      p2=(struct student *)malloc(sizeof(struct student));
      printf("Input the  Number the Name and the Score:\n");
      scanf("%ld%s%ld",&p2->Number,p2->Name,&p2->Score);
  }
  p1->Next=null;
  return(head);
}

/*------------------------------------------*/
/*--------------查看链表内容函数View()------*/
/*------------------------------------------*/
 View(struct student *head)
 {
  struct student *p;
  p=head;
  while(p->Next!=null)
  {
       printf("%ld  %s  %ld\n",p->Number,p->Name,p->Score);
       p=p->Next;
  }
  printf("%ld  %s  %ld\n",p->Number,p->Name,p->Score);
 }

/*-------------------------------------------------*/
/*--------------插入结点函数（前插）Insert()-------*/
/*-------------------------------------------------*/
 Insert(struct student *head,int Num)       /*head为链表头指针，Num插入链表位置*/
{
 int t=1;
 struct student *p1,*p2;
 p1=head;
 if (Num>n||Num<0)
 {
     printf("input error!!!\n");
     return 0;
 }
 
 while(t<Num-1)                  /*找到要插入结点的前一个结点*/
 {
     p1=p1->Next;
     t++;
 }
 p2=(struct student *)malloc(sizeof(struct student));
 printf("Input the  Number the Name and the Score:\n");
 scanf("%ld%s%ld",&p2->Number,p2->Name,&p2->Score);
 p2->Next=p1->Next;
 p1->Next=p2;
 n++;

}

/*------------------------------------------*/
/*------------ 删除结点函数Delnode()--------*/
/*-----------------------------------------*/
 Delnode(struct student *head,int node)
{
 int t=1;
 struct student *p1,*p2;
 p2=head;
 if (node>n||node<1)
 {
     printf("error!!! The node is not exist!");
     return 0;
 }
 while(t<node-1)       /*找到要删除结点的前一个结点*/
 {
     p2=p2->Next;
     t++;
 }
 p1=p2->Next->Next;     /*找到要删除结点的后一个结点*/
 free(p2->Next);        /*释放要删除的结点空间（删除）*/
 p2->Next=p1;           /*前一结点指向后一结点*/
 n--;          
}

/*-------------------------------------------------*/
/*--------------逆序重组链表Invert()-------*/
/*-------------------------------------------------*/
 struct student *Invert(struct student *head)
{
  struct student *p1,*p2;
  p1=head;
  p2=p1->Next;
  head=p2->Next;
  p1->Next=null;
  while(head->Next!=null)
  {
   p2->Next=p1;
   p1=p2;
   p2=head;
   head=head->Next;
  }
  head->Next=p2;
  p2->Next=p1;
  return head;
}

main()
{
 int number1,number2;
 struct student *head;
 head=Creat();
 View(head);

 printf("the n that you want to insert:\n");
 scanf("%d",&number1);
 Insert(head,number1);
 View(head);

 printf("the node that you want to DELETE:\n");
 scanf("%d",&number2);
 Delnode(head,number2);
 View(head);
 
 printf("Inverte the list:\n");
 View(Invert(head));
 
 getch();
}