根据Polya定理: \[ans=\frac{\sum_{d|n}\varphi(d)cal(\frac{n}{d})}{n}\] 其中$cal(n)$表示长度为$n$的无限循环后包含$S$的串的数量. 对于$cal(n)$的计算,考虑用总方案数$2^n$减去单次循环内不包含$S$的方案数. 枚举进入循环时与$S$的KMP指针$k$,然后设$f[i][j]$表示考虑前$i$个位置,KMP指针为$j$的方案数,最终结果为$f[n][k]$. 转移可以用矩阵$G$表示,预处理出$G$的$2^0,2^…

一个队列如果只生产不消费肯定不行的,那么如何及时消费Ring Buffer的数据呢?简单的方案就是当Ring Buffer"写满"的时候一次性将数据"消费"掉.注意这里的"写满"仅仅是指写入位置 index达到了数组最大索引位置,而"消费"也不同于常见的堆栈,队列等数据结构,只是读取缓冲区的数据而不会移除它.一点公益系统 一点公益系统模式 一点公益平台 一点公益APP系统 一点公益商业模式定制找陈牧150-1315-1740(…

OpenCASCADE Ring Type Spring Modeling eryar@163.com Abstract. The general method to directly create an edge is to give a 3D curve as the support(geometric domain) of the edge. The curve maybe defined as a 2D curve in the parametric space of a surface…

最近常收到SOD框架的朋友报告的SOD的SQL日志功能报错:文件句柄丢失.经过分析得知,这些朋友使用SOD框架开发了访问量比较大的系统,由于忘记关闭SQL日志功能所以出现了很高频率的日志写入操作,从而偶然引起错误.后来我建议只记录出错的或者执行时间较长的SQL信息,暂时解决了此问题.但是作为一个热心造轮子的人,一定要看看能不能造一个更好的轮子出来. 前面说的错误原因已经很直白了,就是频繁的日志写入导致的,那么解决方案就是将多次写入操作合并成一次写入操作,并且采用异步写入方式.要保存多次操作的内容…

AlwaysOn Ring Buffers 一些AlwaysOn的诊断信息可以从SQL Server ring buffers.或者从sys.dm_os_ring_buffers.ring buffer在SQL Server启动的时候被创建,SQL Server系统为内部诊断记录警告. 通过以下查询获取所有事件记录 SELECT * FROM sys.dm_os_ring_buffers WHERE ring_buffer_type LIKE '%HADR%' 为了让数据更加可控,可以通过日期,…

传送门 Description A ring is composed of n (even number) circles as shown in diagram. Put natural numbers 1, 2, . . . , n into each circle separately, and the sum of numbers in two adjacent circles should be a prime. Note: the number of first circle sho…

Ring buffers and queues The data structure is extremely simple: a bounded FIFO. One step up from plain arrays, but still, it’s very basic stuff. And if you’re doing system programming, particularly anything involving IO or directly talking to hardwar…

Problem Description A ring is compose of n circles as shown in diagram. Put natural number 1, 2, ..., n into each circle separately, and the sum of numbers in two adjacent circles should be a prime. Note: the number of first circle should always be 1…

Problem Description A ring is compose of n circles as shown in diagram. Put natural number 1, 2, ..., n into each circle separately, and the sum of numbers in two adjacent circles should be a prime. Note: the number of first circle should always be 1…

  Prime Ring Problem  A ring is composed of n (even number) circles as shown in diagram. Put natural numbers into each circle separately, and the sum of numbers in two adjacent circles should be a prime. Note: the number of first circle should always…