【摘要】Solution 我们称 count_pair 为操作 A，find_character 为操作 B。 操作 B 只能做一次，我们考虑先用操作 A 获取尽量多的信息。 对于每次操作 A，为了判断回文性，我们肯定要询问某一对 \(S_i,S_{N-i-1}\) 和另一个数 \(S_k\)。会有 \(3 阅读全文
Subscribe to 博客园_首页’s news feed.
Click on “Follow” and decide if you want to get news from 博客园_首页 via RSS, as email newsletter, via mobile or on your personal news page.
Subscription to 博客园_首页 comes without risk as you can unsubscribe instantly at any time.
You can also filter the feed to your needs via topics and keywords so that you only receive the news from 博客园_首页 which you are really interested in. Click on the blue “Filter” button below to get started.
Title: 博客园_首页