在Python中将二叉树转换为具有级别顺序的列表

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

def levelOrder(root):
    if not root:
        return []

    result = []
    queue = [root]

    while queue:
        level = []
        size = len(queue)

        for _ in range(size):
            node = queue.pop(0)
            level.append(node.val)

            if node.left:
                queue.append(node.left)
            if node.right:
                queue.append(node.right)

        result.append(level)

    return result

# 创建二叉树
root = TreeNode(1)
root.left = TreeNode(2)
root.right = TreeNode(3)
root.left.left = TreeNode(4)
root.left.right = TreeNode(5)
root.right.left = TreeNode(6)
root.right.right = TreeNode(7)

# 将二叉树转换为具有级别顺序的列表
result = levelOrder(root)
print(result)

[[1], [2, 3], [4, 5, 6, 7]]