C单链表实现

 /*
  * LinkNode.c
  *
  *  Created on: Jan 14, 2014
  *      Author: root
  */
 #include <stdlib.h>
 #include <stdio.h>
 #include <malloc.h>
 typedef struct node
 {
     char *data;
     struct node *next;
 }Node,*pNode;

 pNode create();
 void printList(pNode pHead);
 int InsertNode(pNode pHead,int front,char *data);
 char* DeleteNode(pNode pHead,int pos);
 int LengthList(pNode pHead);
 void Sort_List(pNode pHead);
 pNode Reverse_List(pNode pHead);
 int main()
 {

     pNode pHead = NULL;
     int front;
     int choose;
     char* return_val=NULL;
     pHead=create();
     printf("你输入的数据是,\n");
     int length;
     length = LengthList(pHead);
     printf("(长度为%d的单链表):\n",length);
     printList(pHead);
     while()
     {
     printf("是否还要进行如下操作：\n");
     printf("1.插入数据      2.删除数据     3.修改数据     4.链表排序   5.链表逆序   6.退出\n");
     scanf("%d",&choose);
     if(choose!=&&choose!=&&choose!=&&choose!=&&choose!=)
     {
         printf("error:请输入正确的数字!\n");
         break;
     }
     switch(choose)
     {
         case :
         {
             printf("请输入要在第几个节点前插入数据：");
             scanf("%d",&front);
             if(front>length)
             {
                 front = length;
                 printf("Warning:输入结点位置大于链表长度，默认在表尾部添加!\n");
             }
             printf("请输入要插入的数据：");
             char *data = (char*)malloc(sizeof(char*));
             scanf("%s",data);
             if(InsertNode(pHead,front,data)==)
             {
                  printf("插入成功\n插入后的数据是：\n");
                  printList(pHead);
             }else
             {
                  printf("插入失败\n");
             }
                 break;
         }
         case :
         {
             printf("请输入要删除第几个节点的数据：");
             scanf("%d",&front);
             if(front>length)
             {
                 front=length;
                 printf("Warning:输入结点位置大于链表长度，默认删除表最后一个结点!\n");
             }
             return_val = DeleteNode(pHead,front);
             if(return_val==NULL)
             {
                   printf("删除失败。\n");
             }else
             {
                  printf("删除成功。删除的元素是：%s\n",return_val);
             }
                  printf("操作完成后的数据是：\n");
                  printList(pHead);
                  break;
         }
         case :
         {
             printf("暂时没有做这个功能!\n");
             break;
         }
         case :
         {
             Sort_List(pHead);
             break;
         }
         case :
         {
             Reverse_List(pHead);
             break;
         }
         case :
         {
             exit();
         }
         return ;
     }

     }

     return ;
 }

 pNode create()
 {
     int i;
     int len;
     pNode pHead = (pNode)malloc(sizeof(struct node));
     pNode pTail = pHead;
     pTail->next = NULL;
     printf("请输入节点个数：");
     scanf("%d",&len);
     for(i=;i<len;i++)
     {
         char *val=(char*)malloc(sizeof(char*));//Warning.malloc
         printf("第 %d 个节点的数值：",i+);
         scanf("%s",val);
         pNode pNew = (pNode)malloc(sizeof(Node));
         pNew->data = val;
         /*
          *  有序的
          *  1.将尾节点的next指针指向新节点
          *  2.然后把新节点next指针设置为空
          *  3. 最后将新节点作为尾节点
          */
         pTail->next=pNew;
         pNew->next=NULL;
         pTail = pNew;
     }
     printf("create list success!");
     return pHead;
 }

 void printList(pNode pHead)
 {
     pNode p = pHead->next;
     while(p!=NULL)
     {
         printf("%s\n",p->data);
         p=p->next;
     }
     printf("\n");
 }
 int InsertNode(pNode pHead,int front,char *data)
 {
     int i = ;
     pNode _node = pHead;
     pNode pSwap ;

     if((front<) || (_node==NULL))
     {
         printf("error:List is NULL or front<1");
         return -;

     }
     while(i<front-)
     {
         _node = _node->next;
         ++i;
     }
     pNode pNew = (pNode)malloc(sizeof(Node));

     pNew->data=data;
     pSwap = _node->next;
     _node->next = pNew;
     pNew->next = pSwap;

     return ;
 }

 char* DeleteNode(pNode pHead,int pos)
 {
     int i=;
     char *data;
     pNode _node =pHead;
     pNode pSwap ;
     if((pos < ) && (NULL == _node->next))
         {
             printf("failed to delete ! \n");
             return ;
         }
     while(i < pos-)
     {
         _node = _node->next;
         ++i;
     }
     pSwap = _node->next;
     data = pSwap->data;
     _node->next = _node->next->next;
     free(pSwap);
     return data;
 }

 int LengthList(pNode pHead)
 {
     int length = ;
     pNode temp = pHead->next;
     while(temp!=NULL)
     {
         temp=temp->next;
         length++;
     }
     return length;
 }

 void Sort_List(pNode pHead)
 {
     int i , j;
     char* swap ;
     int len=LengthList(pHead);
     pNode m,n;
     for(i=,m=pHead->next;i<len-;i++,m=m->next)
     {
         for(j=i+,n=m->next;j<len;j++,n=n->next)
         {
             if(m->data > n->data)
             {
                 swap = m->data;
                 m->data = n->data;
                 n->data = swap;
             }
         }
     }
     printf("排序完后结果为：\n");
     printList(pHead);
 }
 pNode Reverse_List(pNode pHead)
 {
     if(pHead->next==NULL || pHead->next->next ==NULL)
     {
         return pHead;
     }
     pNode t=NULL;
     pNode p=pHead->next;// first element
     pNode q=pHead->next->next;//second element

     while(q!=NULL)
     {
         t = q->next;
         q->next = p;
         p=q;
         q=t;
     }
     pHead->next->next = NULL;
     pHead->next = p;
     printf("逆序后结果为：\n");
     printList(pHead);
     return pHead;

 }