Python 1-liner
\nclass Solution:\n    def rangeSumBST(self, root, L, R):\n        return root and self.rangeSumBST(root.left, L, R) + self.rangeSumBST(root.right, L, R) + (L <
```\nclass Solution:\n    def rangeSumBST(self, root, L, R):\n        return root and self.rangeSumBST(root.left, L, R) + self.rangeSumBST(root.right, L, R) + (L <= root.val <= R) * root.val or 0\n```\n* More readable\n```\nclass Solution:\n    def rangeSumBST(self, root, L, R):\n        if not root: return 0\n        l = self.rangeSumBST(root.left, L, R)\n        r = self.rangeSumBST(root.right, L, R)\n        return l + r + (L <= root.val <= R) * root.val\n```
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