设计算法实现将单链表中数据逆置后输出。用C语言代码

如下所示：

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

// 定义单链表节点结构体
struct node {
    int data;
    struct node *next;
};

// 定义单链表逆置函数
struct node* reverse(struct node *head) {
    struct node *prev = NULL;
    struct node *curr = head;
    struct node *next;

    while (curr != NULL) {
        next = curr->next;
        curr->next = prev;
        prev = curr;
        curr = next;
    }

    return prev;
}

// 定义单链表输出函数
void print_list(struct node *head) {
    struct node *p = head;
    
    while (p != NULL) {
        printf("%d ", p->data);
        p = p->next;
    }
    
    printf("\n");
}

int main() {
    // 定义单链表 head 节点并初始化
    struct node *head = (struct node*)malloc(sizeof(struct node));
    head->data = 1;
    
    // 定义单链表节点 a, b, c 并初始化
    struct node *a = (struct node*)malloc(sizeof(struct node));
    a->data = 2;
    struct node *b = (struct node*)malloc(sizeof(struct node));
    b->data = 3;
    struct node *c = (struct node*)malloc(sizeof(struct node));
    c->data = 4;
    
    // 手动建立单链表
    head->next = a;
    a->next = b;
    b->next = c;
    c->next = NULL;

    printf("反转前：\n");
    print_list(head);

    // 调用单链表反转函数
    head = reverse(head);

    printf("反转后：\n");
    print_list(head);

    return 0;
}

输出：

反转前：
1 2 3 4 
反转后：
4 3 2 1