wybooooooooo的博客

实在是 美丽的数学啊关于傅里叶变换的博客 讲的很细致 图片非常易于理解http://blog.jobbole.com/70549/大概能明白傅里叶变换是干吗的了但是还是不能明白为什么用傅里叶变换来算多项式求和在多项式中，DFT就是系数表式转换成点值表示的过程。我们熟知的是多项式的系数表示法，通过给定一组  来确定一个唯一的多项式：而多项式还可以有另一种表示法，称为点...

链接：https://www.nowcoder.com/acm/contest/147/A来源：牛客网 时间限制：C/C++ 1秒，其他语言2秒空间限制：C/C++ 262144K，其他语言524288K64bit IO Format: %lld题目描述Niuniu has recently learned how to use Gaussian elimination to ...

多校赛上最近有道题目是gugufishtionProblem DescriptionToday XianYu is too busy with his homework, but the boring GuGu is still disturbing him!!!!!! At the break time, an evil idea arises in XianYu’s mind. ‘Co...

GuGuFishtionTime Limit: 3000/1500 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 1204    Accepted Submission(s): 459 Problem DescriptionToday XianYu is too b...

B. Weakened Common Divisortime limit per test1.5 secondsmemory limit per test256 megabytesinputstandard inputoutputstandard outputDuring the research on properties of the greatest co...

链接：https://www.nowcoder.com/acm/contest/147/E来源：牛客网 时间限制：C/C++ 1秒，其他语言2秒空间限制：C/C++ 262144K，其他语言524288K64bit IO Format: %lld题目描述Niuniu likes to play OSU!We simplify the game OSU to the foll...

加法原理 乘法原理 容斥原理组合数性质1：C(n,0）=C(n,n)=12：C(n,k)=C(n,n-k)3：C(n,k)+C(n,k+1)=C(n+1,k+1)4：C(n,k+1)= C(n,k)*（n-k）/(k + 1） 素数表const int maxn = 10000000 + 10;const int maxp = 700000;int vis[...

A square-free integer is an integer which is indivisible by any square number except 11. For example, 6 = 2 \cdot 36=2⋅3 is square-free, but 12 = 2^2 \cdot 312=22⋅3 is not, because 2^222 is a square n...