Rust  TreeNode implementation could be simplified
Current TreeNode in rust looks like that \n\npub struct TreeNode {\n   pub val: i32,\n   pub left: Option<Rc<RefCell<TreeNode>>>,\n   pub right: Option<Rc<RefCe
Current TreeNode in rust looks like that \n```\npub struct TreeNode {\n   pub val: i32,\n   pub left: Option<Rc<RefCell<TreeNode>>>,\n   pub right: Option<Rc<RefCell<TreeNode>>>,\n }\n ```\n But since each node in tree has only one owner it could be simplified to \n ```\npub struct TreeNode {\n    pub val: i32,\n    pub left: Option<Box<TreeNode>>,\n    pub right: Option<Box<TreeNode>>,\n}\n```\nHow does it help ?\n1. It will work faster since we don\'t do reference counting. So compared to current 12-20 ms we will get  better results for rust.\n2. Code to build tree becomes simpler.\n
['Rust']