98.68% Binary Tree Level Order Traversal with step by step explanation
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\nAlgorithm:\n\n1. Initialize an empty queue.\n2. If the root is not null, 
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\nAlgorithm:\n\n1. Initialize an empty queue.\n2. If the root is not null, add it to the queue.\n3. While the queue is not empty, repeat steps 4-6.\n4. Get the size of the queue and initialize an empty list to store the nodes of the current level.\n5. Loop through the elements of the current level and add them to the list.\n6. For each element of the current level, add its children to the queue.\n7. Add the current level list to the result list.\n8. Return the result list.\n\n# Complexity\n- Time complexity:\nBeats\n98.68%\n- Space complexity:\nBeats\n76.95%\n# Code\n```\nclass Solution:\n   def levelOrder(self, root: Optional[TreeNode]) -> List[List[int]]:\n    # Initialize an empty queue and result list\n    queue = []\n    result = []\n    \n    # If the root is not null, add it to the queue\n    if root:\n        queue.append(root)\n    \n    # While the queue is not empty, repeat steps 4-7\n    while queue:\n        # Get the size of the queue and initialize an empty list to store the nodes of the current level\n        size = len(queue)\n        level = []\n        \n        # Loop through the elements of the current level and add them to the list\n        for i in range(size):\n            node = queue.pop(0)\n            level.append(node.val)\n            \n            # For each element of the current level, add its children to the queue\n            if node.left:\n                queue.append(node.left)\n            if node.right:\n                queue.append(node.right)\n        \n        # Add the current level list to the result list\n        result.append(level)\n    \n    # Return the result list\n    return result\n\n```
['Tree', 'Breadth-First Search', 'Binary Tree', 'Python', 'Python3']