**Solution**

**Find Largest Value in Each Tree Row** https://leetcode.com/problems/find-largest-value-in-each-tree-row/?tab=Description

**Algorithm**

- Do a level order traversal and find the maximum in each row.

```
from collections import deque
class Solution(object):
def largestValues(self, root):
"""
:type root: TreeNode
:rtype: List[int]
"""
q = deque()
if root:
q.append(root)
result = []
while len(q):
result.append(float('-inf'))
for _ in range(len(q)):
top = q.popleft()
result[-1] = max(result[-1], top.val)
if top.left:
q.append(top.left)
if top.right:
q.append(top.right)
return result
```