算法：寻找二叉树中任意两个节点的最近共同父节点

上代码：
public Node nearestParentNode(Node head , Node o1 , Node o2)
{
if(head == null || o1==head || o2 == head )
{
return head
}
Node left = nearestParentNode ( head.left , o1 ,o2 );
Node right = nearestParentNode ( head.right , o1 ,o2 );
if(left != null && right != null)
{
return head;
}
return left!=null?left:right;
}