def test3(self):
s = Solution()
node1 = TreeNode(1)
node2 = TreeNode(2)
node3 = TreeNode(3)
node4 = TreeNode(4)
node5 = TreeNode(5)
node6 = TreeNode(6)
node7 = TreeNode(7)
node4.left = node2
node4.right = node6
node2.left = node1
# node2.right = node3
node6.left = node5
node6.right = node7
res = s.get_next_node(node4, node2)
print res
res = s.get_next_node(node4, node1)
self.assertEqual(node2, res)
print res
def test1(self):
s = Solution()
node1 = TreeNode(1)
node2 = TreeNode(2)
node3 = TreeNode(3)
node4 = TreeNode(4)
node5 = TreeNode(5)
node6 = TreeNode(6)
node7 = TreeNode(7)
node4.left = node2
node4.right = node6
node2.left = node1
node2.right = node3
node6.left = node5
node6.right = node7
res = s.get_next_node(node4, node1)
print res.val
