GCD Equals Mex
You are given an array $A$ containing $N$ positive integers. Count the number of ordered pairs of **disjoint** non-empty subsequences $(S_1, S_2)$ such that $\gcd(S_1) = \text{mex}(S_2)$. Here, the mex of a sequence of integers is the smallest **positive** integer that doesn't appear in it. Print the answer modulo $998244353$. --- Note that: - A subsequence of $A$ is a sequence obtained by t
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solution.cppC++17
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