$ cat ./coding/145-binary-tree-postorder-traversal.md

────────────────────────────────────────────────────────────

145. Binary Tree Postorder Traversal

# 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 postorderTraversal(self, root: TreeNode) -> List[int]:
        if not root:
            return []
        res = []
        res.extend(self.postorderTraversal(root.left))
        res.extend(self.postorderTraversal(root.right))
        res.append(root.val)
        return res

$ ls ./coding/ | grep -v 145-binary-tree-postorder-traversal