BinaryTreeMaximumPathSum.py

class TreeNode:
 def __init__(self, val=0, left=None, right=None):
 self.val = val
 self.left = left
 self.right = right

def getTree(inputValues):
 root = TreeNode(int(inputValues[0]))
 nodeQueue = [root]
 front = 0
 index = 1
 while index < len(inputValues):
 node = nodeQueue[front]
 front = front + 1

 item = inputValues[index]
 index = index + 1
 if item != "null":
 leftNumber = int(item)
 node.left = TreeNode(leftNumber)
 nodeQueue.append(node.left)

 if index >= len(inputValues):
 break

 item = inputValues[index]
 index = index + 1
 if item != "null":
 rightNumber = int(item)
 node.right = TreeNode(rightNumber)
 nodeQueue.append(node.right)

 return (root)
root=getTree([1,2,3])


class Solution:
 def maxPathSum(self, root: TreeNode) -> int:
 if not root:
 return 0
 
 left=self.maxPathSum(root.left)
 right=(self.maxPathSum(root.right))

 maxv=max(left+right+root.val, self.maxPathSum(root.left),self.maxPathSum(root.right)) 

 return maxv

print(Solution().maxPathSum(root))