10/6副本

#include<stdio.h>
#include<stdlib.h>

typedef struct list{
  char data;
  struct list* next;
}*List,L;

List newList();
void showList(List head);
void insert(List head, int i, char X); 

int main()
{
  //初始化链表 
  char ch; 
  char insertNum;
  int insertPlace;
  List head = newList();
  showList(head);
  printf("\n");
  
  //在链表asdfghjkl的第四个位置插入z
  printf("***********************\n");
  printf("下面是插入操作\n");
  printf("请输入你要插入的位置：\n"); 
  scanf("%d",&insertPlace);
  //清空缓冲区
  while(ch=getchar() != '\n'); 
  printf("请输入你插入的数：\n"); 
  scanf("%c",&insertNum);
  insert(head,insertPlace,insertNum);
  showList(head);
  return 0;
  
}

List newList()
{
  
  List head = (List)malloc(sizeof(L));
  List p;
  head->next=NULL;
  p=head;
  while(1)
  {
    char i;
    char ch;
    
    
    printf("请输入一个字符：\n");
    printf("如果要退出，则输入1：\n");
    scanf("%c", &i);
    if(i == '1')
      break;
    // 数据加入 
    List node = (List)malloc(sizeof(L));
    node->data = i;
    node->next = NULL;
    p->next = node;
    p = node;
    
    //清空缓冲区
    while(ch=getchar() != '\n'); 
    
  }
  
  return head;
  
}
//打印链表内容 
void showList(List head)
{
  List p;
  p=head->next;
  while(p != NULL)
  {
    printf("%c",p->data);
    p = p->next;
  }
}

void insert(List head, int i, char X)
{
  //插入opt
  List p, q;
  int count = 1;
  List node = (List)malloc(sizeof(L));
  p = head -> next;
  q = head;
  
  //位置分析
  if(i<1)
  {
    printf("不能插在这\n");
    return;
  }
  
  //insert operator 
  while(p!=NULL)
  {
    if(count<i)
    {
      q = p;
      p = p->next;
      count++;
    }
    else
      break;
  }
  if(p==NULL)
  {
    printf("没有这个位置\n");
    return;
  }
  
  //节点插入
   node->data = X;
   node->next=p;
   q->next=node;
}