c语言如何把链表与文件结合

在C语言中，可以通过文件操作函数将链表与文件结合起来。具体步骤如下：

1. 定义链表的结构体

typedef struct Node {     int data;     struct Node* next; } Node; 

2. 实现链表的插入、删除等操作函数

Node* insert(Node* head, int data) {     Node* newNode = (Node*)malloc(sizeof(Node));     newNode->data = data;     newNode->next = NULL;      if (head == NULL) {         head = newNode;     } else {         Node* temp = head;         while (temp->next != NULL) {             temp = temp->next;         }         temp->next = newNode;     }      return head; }  Node* delete(Node* head, int data) {     Node* current = head;     Node* prev = NULL;      while (current != NULL) {         if (current->data == data) {             if (prev == NULL) { // 删除头节点                 head = current->next;             } else {                 prev->next = current->next;             }             free(current);             break;         }          prev = current;         current = current->next;     }      return head; } 

3. 实现将链表数据写入文件的函数

void writeToFile(Node* head, const char* filename) {     FILE* file = fopen(filename, "w");     if (file == NULL) {         printf("Failed to open file!\n");         return;     }      Node* current = head;     while (current != NULL) {         fprintf(file, "%d\n", current->data);         current = current->next;     }      fclose(file); } 

4. 实现从文件中读取数据到链表的函数

Node* readFromFile(const char* filename) {     FILE* file = fopen(filename, "r");     if (file == NULL) {         printf("Failed to open file!\n");         return NULL;     }      Node* head = NULL;     int data;     while (fscanf(file, "%d", &data) != EOF) {         head = insert(head, data);     }      fclose(file);     return head; } 

这样，就可以通过调用这些函数，将链表中的数据写入文件，或者从文件中读取数据到链表中。例如：

int main() {     Node* head = NULL;      // 插入数据到链表中     head = insert(head, 1);     head = insert(head, 2);     head = insert(head, 3);      // 将链表中的数据写入文件     writeToFile(head, "data.txt");      // 从文件中读取数据到链表     Node* newHead = readFromFile("data.txt");      // 打印链表中的数据     Node* current = newHead;     while (current != NULL) {         printf("%d ", current->data);         current = current->next;     }      // 释放链表内存     while (newHead != NULL) {         Node* temp = newHead;         newHead = newHead->next;         free(temp);     }      return 0; }