Question: I have the following problem Maximum Path Weights in Binary Trees Overview: In this lab, my task is finding the maximum path weight in a

I have the following problem
Maximum Path Weights in Binary Trees
Overview:
In this lab, my task is finding the maximum path weight in a binary tree, where each node has three attributes:
A pointer to the left subtree.
A pointer to the right subtree.
The weight of the node (an integer, potentially negative).
The weight of a path in the tree is defined as the sum of the weights of the nodes along that path. A maximum path is one with the highest possible weight.
Problem:
Given a binary tree T, the objective is to find the maximum weight of a path in T. Special cases include trees where all node weights are zero or negative, in which the maximum path would be empty or consist only of nodes with zero weight.
Input Specification:
The binary tree is provided as a sequence S, which recursively defines the structure of the tree using:
p: the weight of the root node, ranging from -10^4 to 10^4.
flagE and flagD: flags indicating whether the left or right subtrees exist (T for true, F for false).
An example of such a sequence could be:
4 F F (single node tree).
4 T 7 F F T -3 F F (tree with both left and right subtrees).
The number of nodes is guaranteed to be between 1 and 100,000.
Output Specification:
The output should be the maximum path weight in the binary tree.
Examples:
Input: 4 F F
Output: 4
Input: 4 T 7 F F T -3 F F
Output: 11
I have the following code
class TreeNode:
def __init__(self, weight, left=None, right=None):
self.weight = weight
self.left = left
self.right = right
class BinaryTree:
def __init__(self, sequence):
self.sequence = sequence
self.index =0
def build_tree(self):
return self._helper()
def _helper(self):
if self.index >= len(self.sequence):
return None, self.index
# Primeiro, processamos o peso do n, que deve ser um nmero
current_value = self.sequence[self.index]
# Garante que o valor atual seja um nmero
if current_value not in ['T','F']:
try:
weight = int(current_value) # Converte o valor para inteiro
except ValueError:
raise ValueError(f"Erro ao converter '{current_value}' para int. Esperado um nmero.")
else:
raise ValueError(f"Esperado um nmero, mas encontrado '{current_value}'. Verifique a sequncia.")
self.index +=1
# Processa as flags 'T' ou 'F' para as subrvores
flagE = self.sequence[self.index]
self.index +=1
flagD = self.sequence[self.index]
self.index +=1
left_subtree = None
right_subtree = None
if flagE =='T': # Se for 'T', h subrvore esquerda
left_subtree, _= self._helper()
if flagD =='T': # Se for 'T', h subrvore direita
right_subtree, _= self._helper()
# Retorna o n atual com suas subrvores
return TreeNode(weight, left_subtree, right_subtree), self.index
def print_tree(self, node, level=0):
if node is not None:
self.print_tree(node.right, level +1)
print(''*4* level +'->', node.weight)
self.print_tree(node.left, level +1)
class PathSumCalculator:
def max_path_sum(self, root):
def helper(node):
if not node:
return 0
# Calcula os caminhos mximos esquerda e direita
left_max = max(0, helper(node.left))
right_max = max(0, helper(node.right))
# Atualiza o caminho mximo global
current_max = node.weight + left_max + right_max
helper.max_sum = max(helper.max_sum, current_max)
# Retorna o valor mximo para um dos lados (esquerda ou direita)
return node.weight + max(left_max, right_max)
helper.max_sum = float('-inf')
helper(root)
return max(0, helper.max_sum)
def main():
# Substitui sinais de menos especiais e divide a sequncia
sequence = input("Enter the tree sequence: ").replace('','-').replace('','-').split()
try:
binary_tree = BinaryTree(sequence)
tree, _= binary_tree.build_tree()
except (ValueError, IndexError) as e:
print(f"Erro na construo da rvore: {e}")
return
if tree:
print("Estrutura da rvore:")
binary_tree.print_tree(tree)
calculator = PathSumCalculator()
result = calculator.max_path_sum(tree)
print("Maximum path sum:", result)
else:
print("Construo da rvore falhou.")
if __name__=="__main__":
main()
and I'm having the following error
ERROR: Error in tree construction: Expected a number, but found 'F'. Check the sequence.

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