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One day when you were sitting in the couch and eating chips, a guy called you, who claimed that his name was Cuber QQ and he had your girlfriend kidnapped. This seems quite unlikely to you because you do not even have a girlfriend. However, to kill the boring time of Sunday afternoon, you asked how much the ransom is. Surprisingly, Cuber QQ is not interested in your money, the ransom is the answer to a matching problem. It turns out that Cuber QQ is a lover of binary operators, xor especially.
First of all, he shall give you a pair of sequences $a$ and $b$, with length $n$ and $m$ respectively.
Given that $a$ and $b$ do not necessarily have the same length, they do not exactly make a pair. Therefore consecutive subsequences of $a$ are used to make pairs with $b$, That makes $n-m+1$ pairs: $a_l, a_{l + 1}, \ldots, a_{l + m - 1}$ and $b$ for all $1 \le l \le n-m+1$.
For each pair $(a_l, a_{l + 1}, \ldots, a_{l + m - 1}; b)$, we say they are xor-matched if their pairwise-xor's are all available in a pre-defined set $S$. Concretely, the pair is a match if and only if $a_{l+i-1} \oplus b_i \in 2_{\oplus}^{S}$ of all $1 \le i \le m$. $2_{\oplus}^{S}$ is defined as the set of all possible xor-sum of $S$'s subsets, i.e.,
$$2_{\oplus}^{S} = \{ t | t = \bigoplus_{w \in X} w, X \subseteq S \}$$
Note that, since $\{\}$ is always a valid subset of $S$, $0$ is always included in $2_{\oplus}^{S}$.
Now Cuber QQ wants you to tell him, for which $l$'s, $a_l, a_{l + 1}, \cdots, a_{l + m - 1}$ makes a match with $b$. He is not sending your illusory girlfriend back before you correctly answer his question.