93. 平衡二叉树

93. 平衡二叉树 

 

•  描述
•  笔记
•  数据
•  评测

给定一个二叉树,确定它是高度平衡的。对于这个问题,一棵高度平衡的二叉树的定义是：一棵二叉树中每个节点的两个子树的深度相差不会超过1。 

您在真实的面试中是否遇到过这个题？ 

Yes

样例

给出二叉树 A={3,9,20,#,#,15,7}, B={3,#,20,15,7}

A)  3            B)    3 
   /                   
  9  20                 20
    /                  / 
   15   7              15  7

二叉树A是高度平衡的二叉树，但是B不是

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