CF1616H Keep XOR Low

You are given an array $ a_1, a_2, \ldots, a_n $ and an integer $ x $ . Find the number of non-empty subsets of indices of this array $ 1 \leq b_1 < b_2 < \ldots < b_k \leq n $ , such that for all pairs $ (i, j) $ where $ 1 \leq i < j \leq k $ , the inequality $ a_{b_i} \oplus a_{b_j} \leq x $ is held. Here, $ \oplus $ denotes the [bitwise XOR operation](https://en.wikipedia.org/wiki/Bitwise_operation#XOR). As the answer may be very large, output it modulo $ 998\,244\,353 $ .

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