二叉树遍历，运用指针求解其中包含先序遍历，先序、中序、后序遍历的递归算法，二叉树遍历的非递归算法，层次的非递归算法，求二叉树的深度-Binary tree traversal, which contains the first use of pointer traversal solution, first order, in sequence, after traversing the recursive algorithm, binary tree traversal non-recursive algorithm, levels of non-recursive algorithm, binary tree of depth. .