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题目链接：NN and the Optical Illusion 题目原文 NN is an experienced internet user and that means he spends a lot of time on the social media. Once he found the 阅读全文
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题目链接：Build a Contest 题目原文 Arkady coordinates rounds on some not really famous competitive programming platform. Each round features 𝑛 problems of dis 阅读全文
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题目链接：Roman and Browser 题目原文 This morning, Roman woke up and opened the browser with 𝑛 opened tabs numbered from 1 to 𝑛. There are two kinds of tabs: 阅读全文