C语言的链表实现(仅打印最后两个节点)

#include <stdio.h>
#include <stdlib.h>

// 定义链表节点结构
struct Node {
    int data;
    struct Node* next;
};

// 打印链表的最后两个节点
void printLastTwoNodes(struct Node* head) {
    if (head == NULL || head->next == NULL) {
        printf("链表节点数不足两个\n");
        return;
    }

    struct Node* first = head;
    struct Node* second = head->next;

    while (second->next != NULL) {
        first = second;
        second = second->next;
    }

    printf("倒数第二个节点的值：%d\n", first->data);
    printf("最后一个节点的值：%d\n", second->data);
}

int main() {
    // 创建链表节点
    struct Node* head = (struct Node*)malloc(sizeof(struct Node));
    struct Node* second = (struct Node*)malloc(sizeof(struct Node));
    struct Node* third = (struct Node*)malloc(sizeof(struct Node));
    struct Node* fourth = (struct Node*)malloc(sizeof(struct Node));

    // 设置节点的值和指针
    head->data = 1;
    head->next = second;

    second->data = 2;
    second->next = third;

    third->data = 3;
    third->next = fourth;

    fourth->data = 4;
    fourth->next = NULL;

    // 打印最后两个节点
    printLastTwoNodes(head);

    // 释放内存
    free(head);
    free(second);
    free(third);
    free(fourth);

    return 0;
}