我需要评论我的算法，在二叉树中找到最长的连续序列

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

def findLongestConsecutive(root):
    if not root:
        return 0
    
    max_length = 0
    
    def dfs(node, parent_val, length):
        nonlocal max_length
        
        if not node:
            return 0
        
        if parent_val is not None and node.val == parent_val + 1:
            length += 1
        else:
            length = 1
        
        max_length = max(max_length, length)
        
        dfs(node.left, node.val, length)
        dfs(node.right, node.val, length)
    
    dfs(root, None, 0)
    
    return max_length

# 示例用法
root = TreeNode(1)
root.right = TreeNode(3)
root.right.left = TreeNode(2)
root.right.right = TreeNode(4)
root.right.right.right = TreeNode(5)

result = findLongestConsecutive(root)
print(result)  # 输出：3