单链表

单链表就地翻转

递归算法：

  1. void reverse(struct list_node *head)
  2. {
  3.     if(NULL == head || NULL == head->next)
  4.         return;
  5.     reverse1(head->next);
  6.     head->next->next = head;
  7.     head->next = NULL;
  8. }

非递归算法：

  1. void reverse2(struct list_node *head)
  2. {
  3.     if (NULL == head)
  4.     {
  5.         return;
  6.     }
  8.     list_node *curr = head;
  9.     list_node *next = head->next;
  10.     list_node *prev = NULL;
  11.     while (next != NULL) {
  12.         curr->next = prev;
  13.         prev = curr;
  14.         curr = next;
  15.         next = curr->next;
  16.     }
  18.     curr->next = prev;
  19. }