2018年7月21日
A - River Hopscotch
摘要： Every year the cows hold an event featuring a peculiar version of hopscotch that involves carefully jumping from rock to rock in a river. The exciteme 阅读全文
posted @ 2018-07-21 19:21 一无所知小白龙 阅读(250) 评论(0) 推荐(0)
M - Sum
摘要： XXX is puzzled with the question below: 1, 2, 3, ..., n (1 阅读全文
posted @ 2018-07-21 16:36 一无所知小白龙 阅读(269) 评论(0) 推荐(0)