C# Solution
\npublic class Solution \n{\n    public bool BtreeGameWinningMove(TreeNode root, int n, int x) \n    {\n        var node = FindNode(root, x);\n        int l = C
```\npublic class Solution \n{\n    public bool BtreeGameWinningMove(TreeNode root, int n, int x) \n    {\n        var node = FindNode(root, x);\n        int l = CountNodes(node.left), r = CountNodes(node.right);\n        if(l > n/2 || r > n/2 || (n - l - r - 1) > n/2) return true;\n        return false;\n    }\n    \n    private TreeNode FindNode(TreeNode root, int val)\n    {\n        if(root == null || root.val == val) return root;\n        var l = FindNode(root.left, val);\n        if(l != null) return l;\n        return FindNode(root.right, val);\n    }\n    \n    private int CountNodes(TreeNode root)\n    {\n        if(root == null) return 0;\n        return CountNodes(root.left) + CountNodes(root.right) + 1;\n    }\n}\n```
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