10 2018 档案

Miller_Rabin 素数测试
摘要：费马定理的逆定理几乎可以用来判断一个数是否为素数，但是有一些数是判断不出来的，因此，Miller_Rabin测试方法对费马的测试过程做了改进，克服其存在的问题。 推理过程如下（摘自维基百科）： 摘自另一篇博文（手动滑稽）： 原理明白了，就直接上代码了（KuangBin大神的板子）： 代码思路是， M 阅读全文
posted @ 2018-10-25 22:40 Daybreaking 阅读(319) 评论(0) 推荐(0)
线性筛的同时得到欧拉函数 （参考KuangBin）
摘要：线性筛的思想：每个被筛的数是通过它最小的质因子所筛去的。 这种思想保证了每个数只会被筛一次，从而达到线性。并且，这个思想实现起来非常巧妙（见代码注释）！ 因为线性筛的操作中用到了倍数的关系去实现，因此欧拉函数可以顺便也计算出来，根据完全积性函数的性质还有数学推算，直接一条语句就算出来了。 1 #in 阅读全文
posted @ 2018-10-21 21:04 Daybreaking 阅读(260) 评论(0) 推荐(0)
CodeForces 1059C
摘要：Description Let's call the following process a transformation of a sequence of length nn . If the sequence is empty, the process ends. Otherwise, appe 阅读全文
posted @ 2018-10-07 22:07 Daybreaking 阅读(391) 评论(0) 推荐(0)
CodeForces 1059B
摘要：Description Student Andrey has been skipping physical education lessons for the whole term, and now he must somehow get a passing grade on this subjec 阅读全文
posted @ 2018-10-07 21:01 Daybreaking 阅读(567) 评论(0) 推荐(0)
CodeForces 714A
摘要：Description Today an outstanding event is going to happen in the forest — hedgehog Filya will come to his old fried Sonya! Sonya is an owl and she sle 阅读全文
posted @ 2018-10-07 20:50 Daybreaking 阅读(272) 评论(0) 推荐(0)
浅析母函数
摘要：母函数，又称生成函数。 母函数就是一列用来展示一串数字的挂衣架。 ——赫伯特·唯尔夫 。 母函数问题一般是，对于一个问题，抽象出一个生成函数。 以换硬币问题为例，有一元的，四元的，九元的........硬币无数个，问y元钱有几种组合方式。 设一个数的指数为y（组成y元钱），系数为有几种组合方式，开始 阅读全文
posted @ 2018-10-06 10:45 Daybreaking 阅读(203) 评论(0) 推荐(0)
CodeForces 816C 思维
摘要：On the way to school, Karen became fixated on the puzzle game on her phone! The game is played as follows. In each level, you have a grid with n rows 阅读全文
posted @ 2018-10-06 10:08 Daybreaking 阅读(280) 评论(0) 推荐(0)
CodeForces 816B 前缀和
摘要：To stay woke and attentive during classes, Karen needs some coffee! Karen, a coffee aficionado, wants to know the optimal temperature for brewing the 阅读全文
posted @ 2018-10-06 09:42 Daybreaking 阅读(258) 评论(0) 推荐(0)
CodeForces - 1040B Shashlik Cooking
摘要：Long story short, shashlik is Miroslav's favorite food. Shashlik is prepared on several skewers simultaneously. There are two states for each skewer: 阅读全文
posted @ 2018-10-05 11:22 Daybreaking 阅读(337) 评论(0) 推荐(0)
CodeForces - 1009B Minimum Ternary String
摘要：You are given a ternary string (it is a string which consists only of characters '0', '1' and '2'). You can swap any two adjacent (consecutive) charac 阅读全文
posted @ 2018-10-04 11:25 Daybreaking 阅读(278) 评论(0) 推荐(0)
CF 1008C Reorder the Array
摘要：You are given an array of integers. Vasya can permute (change order) its integers. He wants to do it so that as many as possible integers will become 阅读全文
posted @ 2018-10-04 09:30 Daybreaking 阅读(242) 评论(0) 推荐(0)
CodeForces - 1042B
摘要：Berland shop sells nn kinds of juices. Each juice has its price cici. Each juice includes some set of vitamins in it. There are three types of vitamin 阅读全文
posted @ 2018-10-03 17:36 Daybreaking 阅读(360) 评论(0) 推荐(0)