带头结点的单链表的插入，删除，转置，清空，判断空，统计节点数目

//单链表  //带头结点的单链表  #include<stdio.h>  #include<malloc.h>  //单链表的结构体  typedef struct _Node{int data;struct _Node* next;}Node, *LinkList;void Init(LinkList* list){(*list) = (Node*)malloc(sizeof(Node));(*list)->next = NULL;}void InsertHeadList(LinkList list){int val;scanf("%d", &val);while (val != 0){Node* node = (Node*)malloc(sizeof(Node));node->data = val;node->next = list->next;list->next = node;scanf("%d", &val);}}void PrintList(LinkList list){Node* r;r = list->next;while (r != NULL){printf("%d ", r->data);r = r->next;}printf("\n");}void InsertTailList(LinkList list){int val;scanf("%d", &val);Node* s = list;while (s->next != NULL){s = s->next;}while (val != 0){Node* node = (Node*)malloc(sizeof(Node));node->data = val;node->next = NULL;s->next = node;s = node;scanf("%d", &val);}}void DeleteHeadList(LinkList list){if (list->next == NULL){return;}Node* s = list->next;list->next = list->next->next;free(s);}void DeleteTailList(LinkList list){if (list->next == NULL){return;}Node* r = list;while (r->next->next != NULL){r = r->next;}Node* s = r->next;r->next = NULL;free(s);}void ClearList(LinkList list){while (list->next != NULL){DeleteTailList(list);}}bool IsEmpty(LinkList list){if (list->next == NULL){return true;}return false;}int nCountList(LinkList list){int num = 0;Node* r = list->next;while (r != NULL){r = r->next;num++;}return num;}void ReverseList(LinkList list){//三指针法  //一个节点和空链表都是不需要逆转的  if (list->next == NULL || list->next->next == NULL){return;}Node* pre;Node* mid;Node* last;pre = list->next;mid = pre->next;last = mid->next;pre->next = NULL;//如果有三个节点以上我们可以进入循环体进行操作  while (last != NULL){//每次反转一个  mid->next = pre;//节点后移  pre = mid;mid = last;last = last->next;}mid->next = pre;list->next = mid;}int main(void){LinkList list;Init(&list);//单链表的插入  //头插  InsertHeadList(list);//尾插  InsertTailList(list);//统计节点数目  int nCount = nCountList(list);printf("nCount = %d\n", nCount);//单链表的删除  //头删  DeleteHeadList(list);//尾删  DeleteTailList(list);PrintList(list);//带头结点的单链表的逆序  ReverseList(list);PrintList(list);//清空  ClearList(list);//判断空  bool temp = IsEmpty(list);if (temp == true){printf("空\n");}else{printf("不空\n");}return 0;}