D. Distinct Tautonyms - 2019 年 “游族杯” 上海市高校程序设计邀请赛 (同步赛) - ECNU Online Judge

你可以在这里下载。

单点时限: 4.0 sec

内存限制: 1024 MB

样例

Input

4
1 2 1 2

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Input

7
7 6 5 4 3 2 1

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6
1 3 3 3 3 1

Output

NaN

A. As Much As 996 B. Black Peter C. Coprime-Free Permutation D. Distinct Tautonyms E. ECNU MNIST F. Foreigners’ Trouble G. Green-Red Tree H. Huashui Clock I. Induced Metric Space J. Josephus Problem K. Keyboard without Binary Digits L. Liwa River