Python Simple and Fast
class Solution:\n    \n    def maxLevelSum(self, root: TreeNode) -> int:\n        \n        sum = [0]*100\n        \n        def traverse(root,level):\n        
class Solution:\n    \n    def maxLevelSum(self, root: TreeNode) -> int:\n        \n        sum = [0]*100\n        \n        def traverse(root,level):\n            sum[level] += root.val\n            if root.left:\n                traverse(root.left,level+1)\n            if root.right:\n                traverse(root.right,level+1)\n                \n        traverse(root,0)\n        #print(sum)\n        return sum.index(max(sum))+1\n
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