单链表反转实现

来源：互联网发布：网校源码第三方编辑：程序博客网时间：2024/04/29 00:08

struct link
{
struct link *next;
int data;
};

struct link *g_list = 0;

int link_init(struct link ** head)
{
    int i = 0;
    struct link *p = *head;
    struct link *tmp = 0;
    p = malloc(sizeof(struct link));
    p->data = 0;
    p->next = 0;
    for(i = 0; i < 10; i ++)
    {
        tmp = malloc(sizeof(struct link));
        memset(tmp, 0, sizeof(struct link));
        tmp->data = 2*i + 1;
        tmp->next = p;
        p=tmp;
    }
    *head = p;
    return 0;
}

void link_print(struct link *head)
{
    int count = 0;
    struct link *p = head;
    printf("the link data is :/r/n");
    while(p != 0)
    {
        printf("%2u ", p->data);
        p = p->next;
        count++;
    }

printf("/r/ntotol count = %u/r/n", count);
}

void link_reverse(struct link **head)
{
    struct link * p = *head;
    struct link *q = p->next;
    struct link *r = 0;
    while(q != 0)
    {
        r = q->next;
        q->next = p;
        p = q;
        q = r;
    }
    (*head)->next = 0;
    *head = p;
}

void link_free(struct link *head)
{
    struct link *p = head;
    struct link *tmp = 0;
    while(p != 0)
    {
        tmp = p->next;
        free(p);
        p=tmp;
    }
}

int main()
{
    link_init(&g_list);
    link_print(g_list);
    link_reverse(&g_list);
    link_print(g_list);

    getchar();

link_reverse(&g_list);
link_print(g_list);

getchar();
link_free(g_list);

}