Replay：The 2019 ICPC Nanjing Regional Contest （Training）

A B C D E F G H I J K 2019 Nanjing 2020/9/12 ⭕ ⭕ ⭕ ✔ ✔ ⭕ ✔ ✔ ⭕ Replay: A solved by sanshuiii. 0:20 (1 try) 签到，结果为 n + 1 2 + 1 \frac{n+1}{2}+1 2n+1​+1，当n特别小时特判一下 B solved by idyllic && sanshuiii. 3:18

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