摘要: There are several ancient Greek texts that contain descriptions of the fabled island Atlantis. Some of these texts even include maps of parts of the i 阅读全文
posted @ 2018-09-18 12:39 hinata_hajime 阅读(103) 评论(0) 推荐(0) 编辑
摘要: 题意:给你一组括号序列,让你进行染色,对于每个括号,有无色,红色,蓝色三种方案。染色需要满足这样的条件:互相匹配的括号,有且只有一个有颜色,相邻的括号不能颜色相同(可以同为无色),问合法的染色方案数(答案%1e9+7) 分析:根据题意能够看出是区间DP,并且状态转移的时候,依赖于左右两端的颜色,所以 阅读全文
posted @ 2018-09-18 12:14 hinata_hajime 阅读(158) 评论(0) 推荐(0) 编辑