摘要: Natasha's favourite numbers are 𝑛n and 11, and Sasha's favourite numbers are 𝑚m and −1−1. One day Natasha and Sasha met and wrote down every possibl 阅读全文
posted @ 2019-09-05 16:44 hit_yjl 阅读(250) 评论(0) 推荐(0) 编辑