Java Binary Tree Lowest Common Ancestor (LCA)

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public class JavaBinaryTreeLCA {

	public static class TreeNode {
		int data;
		TreeNode left;
		TreeNode right;

		TreeNode(int data) {
			this.data = data;
		}
	}

	public static TreeNode lowestCommonAncestor(TreeNode root, TreeNode a, TreeNode b) {
		if (root == null)
			return null;
		if (root.data == a.data || root.data == b.data)
			return root;

		TreeNode left = lowestCommonAncestor(root.left, a, b);
		TreeNode right = lowestCommonAncestor(root.right, a, b);

		if (left != null && right != null)
			return root;
		if (left == null)
			return right;
		else
			return left;

	}

	public static void main(String[] args) {
		JavaBinaryTreeLCA bi = new JavaBinaryTreeLCA();
		TreeNode rootNode = createBinaryTree();
		System.out.println("Lowest common ancestor for node 5 and 30:");
		TreeNode node5 = new TreeNode(5);
		TreeNode node30 = new TreeNode(30);
		System.out.println(lowestCommonAncestor(rootNode, node5, node30).data);

	}

	public static TreeNode createBinaryTree() {

		TreeNode rootNode = new TreeNode(40);
		TreeNode node20 = new TreeNode(20);
		TreeNode node10 = new TreeNode(10);
		TreeNode node30 = new TreeNode(30);
		TreeNode node60 = new TreeNode(60);
		TreeNode node50 = new TreeNode(50);
		TreeNode node70 = new TreeNode(70);
		TreeNode node5 = new TreeNode(5);
		TreeNode node45 = new TreeNode(45);
		TreeNode node55 = new TreeNode(55);

		rootNode.left = node20;
		rootNode.right = node60;

		node20.left = node10;
		node20.right = node30;

		node60.left = node50;
		node60.right = node70;

		node10.left = node5;
		node50.right = node55;
		return rootNode;
	}
}

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