后序遍历的遍历中，某一个节点要被输出，在两种情况下：当前节点的左右孩子为空；当前节点的左右孩子已经被访问。
第一种情况非常容易判断
第二种情况需要记录访问过的节点，显然当前节点如果有孩子，则对它的访问会紧跟在它的孩子节点之后，无论是左右。
所以只需记录每次访问的节点，就Ok!
[1]http://www.cnblogs.com/changchengxiao/p/3416402.html
时间： 2024-10-03 22:55:20
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