40         node* next;  member
42             data(t), data2(t2), prev(p), next(n) {}  in node()
69             head=head->next;  in ~Map()
86         tmp = tmp->next;  in find()
102         tmp = tmp->next;  in find_ele()
127         tmp = tmp->next;  in show()
138         tmp = tmp->next;  in size()
151         tail->prev->next = tail;  in insert()
182             tmp = tmp->next;  in erase()
185             tempnode->next = NULL;  in erase()
193             prevnode->next = NULL;  in erase()
202             prevnode->next = tmp->next;  in erase()
203             tmp->next->prev = prevnode->next;  in erase()
211         tmp = tmp->next;  in erase()
227         tempnode->next = NULL;  in eraseall()
228         head = head->next;  in eraseall()