Node* reveser(Node *head) { if (head == NULL) { return NULL; } Node* pre = NULL; Node* next = NULL; while (head != NULL) { next = head->next; head->next = pre; head->pre = next; pre = head; head = next; } pre->pre = NULL; return pre; }
Node* reveser(Node *head) { if (head == NULL) { return NULL; } Node* pre = NULL; Node* next = NULL; while (head != NULL) { next = head->next; head->next = pre; head->pre = next; pre = head; head = next; } pre->pre = NULL; return pre; }