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# 2583. Kth Largest Sum in a Binary Tree
"""
you are given the 'root' of a binary tree and a positive integer 'k'. the
level sum in the tree is the sum of the values of the nodes that are on the
same level. return the k'th largest level sum in the tree (not necessarily
distinct). if there are fewer than 'k' levels in the tree, return -1. note
that two nodes are on the same level if they have the same distance from the
root.
"""
# Definition for a binary tree node.
class TreeNode(object):
def __init__(self, val=0, left=None, right=None):
self.val = val
self.left = left
self.right = right
class Solution(object):
def kthLargestLevelSum(self, root, k):
"""
:type root: Optional[TreeNode]
:type k: int
:rtype: int
"""
vals = []
stack = [(root, 0)]
while stack:
node, i = stack.pop()
if i == len(vals):
vals.append(0)
vals[i] += node.val
if node.left:
stack.append((node.left, i + 1))
if node.right:
stack.append((node.right, i + 1))
return sorted(vals, reverse=True)[k - 1] if len(vals) >= k else -1
if __name__ == "__main__":
obj = Solution()
print(obj.kthLargestLevelSum(root=[5, 8, 9, 2, 1, 3, 7, 4, 6], k=2))
print(obj.kthLargestLevelSum(root=[1, 2, None, 3]))
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