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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/**
 * Definition of TreeNode:
 * class TreeNode {
 * public:
 *     int val;
 *     TreeNode *left, *right;
 *     TreeNode(int val) {
 *         this->val = val;
 *         this->left = this->right = NULL;
 *     }
 * }
 */


class Solution {
public:
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     * @param root: The root of binary tree.
     * @return: True if this Binary tree is Balanced, or false.
     */
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        // write your code here
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    }

    int isSubTreeBalanced(TreeNode *root) {
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            return 0;
        }

        int left = isSubTreeBalanced(root->left);
        int right = isSubTreeBalanced(root->right);
        
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            return -1;
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