不一定对，仅供参考

在单链表中开始理解错误的地方

这两个并不等价，前者用于后移，后者会破坏链表结构

list = list->next;    list->next = list->next->next; 

#include <stdio.h>
#include <stdlib.h>
typedef struct Node{int data;struct Node* next;
}Node;
// 初始化，创建头结点返回
Node* list_init()
{Node* list = (Node*)malloc(sizeof(Node));list->next = NULL;list->data = 0;return list;
}
// 头插法
int head_insert(Node* list,int data)
{Node* node = (Node*)malloc(sizeof(Node));node->next = NULL;node->data = data;node->next = list->next;// 连接后面结点list->next = node; // 头后添加list->data++; // 记录个数return 0;
}
// 尾插法
int tail_insert(Node* list,int data)
{Node* node = (Node*)malloc(sizeof(Node));node->next = NULL;node->data = data;Node* head = list;while(list->next != NULL){list = list->next;//list->next = list->next->next; //改变list,注释方法错误}node->next = list->next;list->next = node;list->next->data = data;list = head;head->data++;return 0;
}
int delete_node(Node* list,int data)
{if(list == NULL || list->next == NULL) return -1;Node* pre = list;Node* current = list->next;while(current != NULL){if(current->data == data){pre->next = current->next;list->data--;free(current);return 0;}pre = current;current = current->next; }return -1;}
void printf_list(Node* list)
{Node* current = list;while(current->next != NULL){printf("%d\t",current->next->data);current = current->next;}printf("\n");printf("num:%d\n",list->data);
}
void free_list(Node* list)
{while(list != NULL){Node* current = list;list = list->next;free(current);}
}
int main(int argc, char const *argv[])
{Node* list = list_init();tail_insert(list,3);tail_insert(list,4);tail_insert(list,5);tail_insert(list,6);tail_insert(list,7);delete_node(list,4);printf_list(list);return 0;
}