2019-11-02 12:07:41 +08:00
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# 55.2 平衡二叉树
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[NowCoder](https://www.nowcoder.com/practice/8b3b95850edb4115918ecebdf1b4d222?tpId=13&tqId=11192&tPage=1&rp=1&ru=/ta/coding-interviews&qru=/ta/coding-interviews/question-ranking&from=cyc_github)
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## 题目描述
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平衡二叉树左右子树高度差不超过 1。
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2019-12-06 10:11:23 +08:00
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<div align="center"> <img src="https://cs-notes-1256109796.cos.ap-guangzhou.myqcloud.com/af1d1166-63af-47b6-9aa3-2bf2bd37bd03.jpg" width="250px"/> </div><br>
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2019-11-02 12:07:41 +08:00
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## 解题思路
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```java
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private boolean isBalanced = true;
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public boolean IsBalanced_Solution(TreeNode root) {
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height(root);
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return isBalanced;
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}
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private int height(TreeNode root) {
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if (root == null || !isBalanced)
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return 0;
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int left = height(root.left);
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int right = height(root.right);
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if (Math.abs(left - right) > 1)
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isBalanced = false;
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return 1 + Math.max(left, right);
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}
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```
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