链表反转

Node* rever(Node* Head)
{   
    if(Head == NULL || Head->next == NULL)
        return Head;
    Node* cur, next, next_next;
    cur = Head; 
    next = cur->next;
    while(cur->next != NULL){
        next_next = next->next;
        next->next = cur;
        cur = next;
        next = next_next;
    }
    Head->next = NULL;
    return cur;
}