用c语言写单链表的就地逆置

好的，下面是用C语言实现单链表就地逆置的代码：

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

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

Node *createList(int n) {
    Node *head = NULL, *tail = NULL;
    int i, val;

    for (i = 0; i < n; i++) {
        printf("请输入第%d个节点的值：", i + 1);
        scanf("%d", &val);

        Node *newNode = (Node *)malloc(sizeof(Node));
        newNode->data = val;
        newNode->next = NULL;

        if (head == NULL) {
            head = newNode;
            tail = newNode;
        } else {
            tail->next = newNode;
            tail = newNode;
        }
    }

    return head;
}

void printList(Node *head) {
    while (head != NULL) {
        printf("%d ", head->data);
        head = head->next;
    }
    printf("\n");
}

void reverseList(Node **head) {
    if (*head == NULL || (*head)->next == NULL) {
        return;
    }

    Node *prev = NULL, *curr = *head, *next = NULL;
    while (curr != NULL) {
        next = curr->next;
        curr->next = prev;
        prev = curr;
        curr = next;
    }

    *head = prev;
}

int main() {
    int n;
    printf("请输入链表的长度：");
    scanf("%d", &n);

    Node *head = createList(n);

    printf("原始链表：");
    printList(head);

    reverseList(&head);

    printf("逆置后的链表：");
    printList(head);

    return 0;
}

该代码首先定义了一个`Node`结构体表示链表中的节点，包含了一个整数`data`和下一个节点的指针`next`。然后通过`createList`函数创建了一个长度为`n`的单链表，通过`printList`函数打印出了原始链表。接着通过`reverseList`函数实现了单链表的就地逆置，最后再次通过`printList`函数打印出了逆置后的链表。