Balanced Binary Tree LeetCode solution in Java

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/**
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 * Definition for a binary tree node. public class TreeNode { int val; TreeNode left; TreeNode
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 * right; TreeNode() {} TreeNode(int val) { this.val = val; } TreeNode(int val, TreeNode left,
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 * TreeNode right) { this.val = val; this.left = left; this.right = right; } }
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 */
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class Solution {
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  public int treeHeight(TreeNode root) {
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    if (root == null) return 0;
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    int left = treeHeight(root.left);
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    int right = treeHeight(root.right);
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    return (Math.max(left, right) + 1);
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  }
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  public boolean isBalanced(TreeNode root) {
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    if (root == null) return true;
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    boolean leftBalanced = isBalanced(root.left);
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    boolean rightBalanced = isBalanced(root.right);
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    int leftHeight = treeHeight(root.left);
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    int rightHeight = treeHeight(root.right);
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    // Return true only when all conditions are true
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    return (leftBalanced && rightBalanced && Math.abs(leftHeight - rightHeight) <= 1);
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  }
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}