摘要: AtCoder Regular Contest 082 D Derangement 与下标相同与下个交换就好了。。。。 Define a sequence of ’o’ and ’x’ of length N as follows: if pi ̸= i, the i-th symbol is ’o’ 阅读全文
posted @ 2017-09-02 22:03 ╰追憶似水年華ぃ╮ 阅读(173) 评论(0) 推荐(0)