二叉查找树随意两个节点的最近共同父节点

找出二叉查找树Binary search tree上任意两个节点的最近共同父节点 

public class Solution {
    public static int findFather(BinarySearchTreeNode root, BinarySearchTreeNode n1, BinarySearchTreeNode n2) {
        if (n1.value < root.value && n2.value > root.value) {
            return root.value;
        }
        if (n1.value < root.value && n2.value < root.value) {
            return findFather(root.left, n1, n2);
        } else if (n1.value > root.value && n2.value > root.value) {
            return findFather(root.right, n1, n2);
        }
        return -1;
    }
}