# 55.2 平衡二叉树
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## 题目描述
平衡二叉树左右子树高度差不超过 1。
## 解题思路
```java
private boolean isBalanced = true;
public boolean IsBalanced_Solution(TreeNode root) {
height(root);
return isBalanced;
}
private int height(TreeNode root) {
if (root == null || !isBalanced)
return 0;
int left = height(root.left);
int right = height(root.right);
if (Math.abs(left - right) > 1)
isBalanced = false;
return 1 + Math.max(left, right);
}
```