Problem A: 朋友 - HUSTOJ

Memory Limit：128 MB Time Limit：1.000 S

Judge Style：Text Compare Creator：

Submit：7 Solved：6

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题解：https://www.bilibili.com/video/BV1Qe411C7k1?spm_id_from=333.788.recommend_more_video.10&vd_source=ed609f9463861996afb742d2bd8b5a46
另外解法：https://www.bilibili.com/video/BV1nc411q7Km?spm_id_from=333.788.recommend_more_video.8&vd_source=ed609f9463861996afb742d2bd8b5a46

2015慈溪