c++链表基本操作

 #include <stdlib.h>
 #include <malloc.h>
 #include <stdio.h> typedef struct Node
 {
     int data;
     struct Node *pNext;
 }NODE,*PNODE; PNODE create_list(void);
 void traverse_list(PNODE);
 bool is_empty(PNODE pHead);
 int length_list(PNODE);
 bool insert_list(PNODE, int, int);
 bool delete_list(PNODE,int,int*);
 void sort_list(PNODE); int main(void)
 {
     PNODE pHead = NULL;
     int val;
     pHead = create_list();
     sort_list(pHead);
     if (delete_list(pHead, , &val))
     {
         printf("delete %d ok!\n",val);
     }
     else
     {
         printf("delete wrong");
     }
     traverse_list(pHead);
     int len = length_list(pHead);
     if (is_empty(pHead))
     {
         printf("list is empty!");
     }
     else
     {
         printf("list isn't empty！");
     }
     return ;
 } PNODE create_list(void)
 {
     int len;
     int val;//用于存放用户输入的结点的值
     printf("请输入链表的长度：len=");
     scanf("%d", &len);
     PNODE pHead = (PNODE)malloc(sizeof(Node));     if (NULL == pHead)
     {
         printf("分配失败，程序终止!");
         exit(-);
     }
     PNODE pTail = pHead;
     pTail->pNext = NULL;     for (int i = ; i < len; ++i)
     {
         printf("请输入第%d个节点的值", i + );
         scanf("%d", &val);
         PNODE pNew = (PNODE)malloc(sizeof(Node));
         if (NULL == pNew)
         {
             printf("分配失败，程序终止!");
             exit(-);
         }
         pNew->data = val;
         pTail->pNext = pNew;
         pNew->pNext = NULL;
         pTail = pNew;
     }
     return pHead;
 } void traverse_list(PNODE pHead)
 {
     PNODE p = pHead->pNext;
     while (NULL != p)
     {
         printf("%d", p->data);
         p = p->pNext;
     }
     printf("\n");
 } bool is_empty(PNODE pHead)
 {
     if (NULL == pHead->pNext)
     {
         return true;
     }
     return false;
 } int length_list(PNODE pHead)
 {
     int length = ;
     PNODE p = pHead->pNext;
     while (NULL != p)
     {
         length++;
         p = p->pNext;
     }
     return length;
 } void sort_list(PNODE pHead)
 {
     int i, j, t;
     int len = length_list(pHead);
     PNODE p, q;
     for (i = , p = pHead->pNext; i < len - ; ++i, p=p->pNext)
     {
         for (j = i + , q = p->pNext; j < len; ++j, q = q->pNext)
         {
             if (p->data > q->data)
             {
                 t = p->data;
                 p->data = q->data;
                 q->data = t;
             }
         }
     }
     return;
 }
 //在pHead指向链表的第pos个节点的前面插入一个新的节点，该节点的值为value,pos从1开始
 bool insert_list(PNODE pHead, int pos, int value)
 {
     int i = ;
     PNODE p = pHead;
     while (NULL != p && i < pos - )
     {
         p = p->pNext;
         ++i;
     }
     if (i > pos -  || NULL == p)
         return false;
     PNODE pNew = (PNODE)malloc(sizeof(NODE));
     if (NULL == pNew)
     {
         printf("动态分配内存失败！\n");
         exit(-);
     }
     pNew->data = value;
     PNODE q = p->pNext;
     p->pNext = pNew;
     pNew->pNext = q;
     return true;
 } bool delete_list(PNODE pHead, int pos, int *pVal)
 {
     int i = ;
     PNODE p = pHead;
     while (NULL != p->pNext && i < pos - )
     {
         p = p->pNext;
         ++i;
     }
     if (i > pos -  || NULL == p->pNext)
     {
         return false;
     }
     PNODE q = p->pNext;
     *pVal = q->data;
     //删除p节点后面的节点
     p->pNext = p->pNext->pNext;
     free(q);
     q = NULL;
     return true;
 } /*
 1.链表的删除，比如删除p后的节点，如何操作？有时很容易遗漏free(r)的操作，导致内存泄漏。
 可以如下操作：
 r = p->next;
 p->next = r->next;
 free(r);
 */