c++ - 无需额外存储的二叉搜索树迭代前序遍历

Question

对于中序二叉搜索树遍历，有一种迭代算法不使用辅助内存(堆栈、父指针、已访问标志)，称为Morris Traversal。 .有没有类似的前序后序遍历算法？

Answer 1

刚想出了一个先序遍历的解决方案，可能行得通

Initialize current as root 
While current is not NULL
If current does not have right child
  a) print current root
  b) Go to the left, i.e., current = current->left
Else
  a) print current root
  a) Make the whole right sub-tree of current as the left node of the rightmost child in the left sub tree(inorder predecessor of current)
  b) Go to the left child, i.e., current = current->left

如果算法有问题请评论