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# 590. N-ary Tree Postorder Traversal
"""
given the 'root' of an n-ary tree, return the postorder traversal of its
nodes' values. nary-tree input serialisation is represented in their level
order traversal. each group of children is separated by the None value.
"""
# Definition for a Node.
class Node(object):
def __init__(self, val=None, children=None):
self.val = val
self.children = children
class Solution(object):
def postorder(self, root):
"""
:type root: Node
:rtype: List[int]
"""
ans = []
if not root:
return ans
def dfs(root, ans):
for child in root.children:
dfs(child, ans)
ans.append(root.val)
dfs(root, ans)
return ans
if __name__ == "__main__":
obj = Solution()
print(obj.postorder(root=[1, None, 3, 2, 4, None, 5, 6]))
print(
root=[
1,
None,
2,
3,
4,
5,
None,
None,
6,
7,
None,
8,
None,
9,
10,
None,
None,
11,
None,
12,
None,
13,
None,
None,
14,
]
)
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