用C语言设计一个算法,通过遍历一趟,将链表中所有结点的链接方向逆转,仍利用原表的存储空间。

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

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

Node *reverseList(Node *head) {
    Node *prev = NULL;
    Node *curr = head;
    Node *next = NULL;

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

    return prev;
}

void printList(Node *head) {
    Node *curr = head;

    while (curr != NULL) {
        printf("%d ", curr->data);
        curr = curr->next;
    }
    printf("\n");
}

int main() {
    // create a linked list
    Node *head = (Node *) malloc(sizeof(Node));
    head->data = 1;
    head->next = (Node *) malloc(sizeof(Node));
    head->next->data = 2;
    head->next->next = (Node *) malloc(sizeof(Node));
    head->next->next->data = 3;
    head->next->next->next = NULL;

    // print the original list
    printf("Original list: ");
    printList(head);

    // reverse the list
    head = reverseList(head);

    // print the reversed list
    printf("Reversed list: ");
    printList(head);

    return 0;
}

输出：

Original list: 1 2 3 
Reversed list: 3 2 1