单链表的销毁

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

void destroryNode(Node *head)
{
        Node *p = head->next;
        Node *q = NULL;
        Node *r = NULL;
        for(q=p; q->next!=NULL; q=r)
        {
                r = q->next;
                free(q);
                q->next=NULL;
        }
        free(r);
        free(head);
        head=NULL;
}