#590

N-ary Tree Postorder Traversal

newbie · 160 · lc easy +14 · verified · 81% accepted · 2,754 likes · top 93%

Description

Given the root of an N-ary tree, return the list of node values visited in postorder (children left to right before the root). The tree is serialized in level-order with null separating each node's children.

Example 1:

Input: root = [1,null,3,2,4,null,5,6]

Output: [5,6,3,2,4,1]

Example 2:

Input: root = [1,null,2,3,4,5,null,null,6,7,null,8,null,9,10,null,null,11,null,12,null,13,null,null,14]

Output: [2,6,14,11,7,3,12,8,4,13,9,10,5,1]

Code

"""
# Definition for a Node.
class Node:
    def __init__(self, val: Optional[int] = None, children: Optional[List['Node']] = None):
        self.val = val
        self.children = children
"""

class Solution:
    def postorder(self, root: 'Node') -> List[int]:

"""
# Definition for a Node.
class Node:
    def __init__(self, val: Optional[int] = None, children: Optional[List['Node']] = None):
        self.val = val
        self.children = children
"""

class Solution:
    def postorder(self, root: 'Node') -> List[int]: