LeetCode #102: Binary Tree Level Order Traversal
β’ 83 words β’ 1 min β’ updated
LeetCode #102: Binary Tree Level Order Traversal:
python
from collections import deque
# Definition for a binary tree node.
# class TreeNode:
# def __init__(self, val=0, left=None, right=None):
# self.val = val
# self.left = left
# self.right = right
class Solution:
def levelOrder(self, root: Optional[TreeNode]) -> List[List[int]]:
if not root:
return []
ans = []
queue = deque([root])
while queue:
level = []
for _ in range(len(queue)):
node = queue.popleft()
level.append(node.val)
for child in [node.left, node.right]:
if child:
queue.append(child)
ans.append(level)
return ans