# https://leetcode.com/problems/find-largest-value-in-each-tree-row

from typing import Deque, List, Optional, Tuple
from collections import deque

class TreeNode:
    def __init__(self, val=0, left=None, right=None):
        self.val = val
        self.left = left
        self.right = right
class Solution:
    def largestValues(self, root: Optional[TreeNode]) -> List[int]:
        d: Deque[Tuple[TreeNode, int]] = deque()
        result: List[int] = []
        if root is not None:
            d.append((root, 1))
        while len(d) > 0:
            node, level = d.popleft()
            if len(result) < level:
                result.append(node.val)
            else:
                result[level - 1] = max(result[level - 1], node.val)
            if node.left is not None:
                d.append((node.left, level + 1))
            if node.right is not None:
                d.append((node.right, level + 1))
        return result