LeetCode 589 N-ary Tree Preorder Traversal 解題報告
阿新 • • 發佈:2019-02-10
append 遞歸 遍歷 lee tco pytho its not list
題目要求
Given an n-ary tree, return the preorder traversal of its nodes‘ values.
題目分析及思路
題目給出一棵N叉樹,要求返回結點值的前序遍歷。可以使用遞歸的方法做。因為是前序遍歷,所以最開始就加入根結點的值。
python代碼
"""
# Definition for a Node.
class Node:
def __init__(self, val, children):
self.val = val
self.children = children
"""
class Solution:
def preorder(self, root: ‘Node‘) -> ‘List[int]‘:
order = []
if not root:
return order
order.append(root.val)
for child in root.children:
order.extend(self.preorder(child))
return order
LeetCode 589 N-ary Tree Preorder Traversal 解題報告