# DeFinition for a binary tree node.
# class TreeNode(object):
# def __init__(self,x):
# self.val = x
# self.left = None
# self.right = None
class Solution(object):
def rightSideView(self,root):
"""
:type root: TreeNode
:rtype: List[int]
"""
res = []
if not root:
return res
queue = []
queue.append(root)
while queue:
level = []
for i in range(len(queue)):
node = queue.pop(0)
level.append(node.val)
if node.left:
queue.append(node.left)
if node.right:
queue.append(node.right)
res.append(level.pop())
return res
