Minimum common ancestor of binary tree

public class Main {


    private static TreeNode<Integer> ans;

    private static boolean dfs(TreeNode<Integer> root, TreeNode<Integer> p, TreeNode<Integer> q) {

        if (root == null) {
            return false;
        }

        boolean lson = dfs(root.left, p, q);

        boolean rson = dfs(root.right, p, q);

        if ((lson && rson) || ((root.val.equals(p.val) || root.val.equals(q.val)) && (lson || rson))) {
            ans = root;
        }

        return lson || rson || (root.val.equals(p.val) || root.val.equals(q.val));
    }

    public static TreeNode<Integer> lowestCommonAncestor(TreeNode<Integer> root, TreeNode<Integer> p, TreeNode<Integer> q) {

        dfs(root, p, q);

        return ans;

    }


    public static void main(String[] args) {

        TreeNode<Integer> root = new TreeNode<Integer>(2);

        root.left = new TreeNode<>(1);
        root.right = new TreeNode<>(3);

        System.out.println(lowestCommonAncestor(root, root.left, root.right).val);

    }
}