Maximum Difference Between Node and Ancestor 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 maxAncestorDiff(TreeNode root) {
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    if (root == null) return 0;
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    return find(root, Integer.MAX_VALUE, Integer.MIN_VALUE);
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  }
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  public int find(TreeNode root, int min, int max) {
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    if (root == null) return Math.abs(max - min);
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    min = Math.min(min, root.val);
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    max = Math.max(max, root.val);
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    return Math.max(find(root.left, min, max), find(root.right, min, max));
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  }
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}