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E. Hanging Hearts Pak Chanek has $n$ blank heart-shaped cards. Card $1$ is attached directly to the wall while each of the other cards is hanging onto 阅读全文
摘要：
D. Count GCD You are given two integers $n$ and $m$ and an array $a$ of $n$ integers. For each $1 \le i \le n$ it holds that $1 \le a_i \le m$. Your t 阅读全文