08 2019 档案

杜教筛之逆运算2
摘要：有了杜教筛的式子我们可以干很多事 $$\sum_{i=1}^nf g(i)=\sum_{i=1}^nf(i)\sum_{j=1}^{\lfloor\frac{n}{i}\rfloor}g(j)$$ 对于这种两种形式的式子可以用杜教筛式子秒杀 $$ 1.\sum_{i=1}^n\lfloor\frac 阅读全文
posted @ 2019-08-31 21:39 zmy蒟蒻 阅读(270) 评论(0) 推荐(0)
欧拉心算
摘要："传送门" 解法： $$ \begin{align} \sum_{i=1}^n\sum_{j=1}^n\phi(gcd(i,j))&=\sum_{d=1}\phi(d)\sum_{i=1}^n\sum_{j=1}^n[d==gcd(i,j)]\\ &=\sum_{d=1}^n\phi(d)\sum_ 阅读全文
posted @ 2019-08-31 19:34 zmy蒟蒻 阅读(501) 评论(1) 推荐(0)
树套树-权值线段树套区间线段树
摘要：树套树留坑 线段树套线段树： "K大数查询" ~~~c++ include include include include include include include include define rep(i,a,b) for(int i=(a);i=(b); i) using namespac 阅读全文
posted @ 2019-08-28 14:12 zmy蒟蒻 阅读(213) 评论(0) 推荐(0)
树套树-线段树套平衡树
摘要：树套树留坑 线段树套平衡树： "二逼平衡树" ~~~c++ include include include include include include include include pragma GCC optimize(2) define rep(i,a,b) for(int i=(a);i 阅读全文
posted @ 2019-08-24 00:29 zmy蒟蒻 阅读(215) 评论(0) 推荐(0)
Link Cut Tree
摘要：Link Cut Tree留坑 LCT： "LCT模板" ~~~c++ include include include include include include include include define rep(i,a,b) for(int i=(a);i=(b); i) using na 阅读全文
posted @ 2019-08-20 17:26 zmy蒟蒻 阅读(122) 评论(0) 推荐(0)
可持久化线段树（主席树）
摘要：主席树留坑 可持久化权值线段树： "区间第k小数" ~~~c++ include include include include include include include include define rep(i,a,b) for(int i=(a);i=(b); i) using names 阅读全文
posted @ 2019-08-19 21:29 zmy蒟蒻 阅读(132) 评论(0) 推荐(0)
带输入值的莫反解法
摘要：~~8.16杭二的莫反题没有推出来~~ 求$\sum_{i=1}^n\sum_{j=1}^nlcm(a_i,a_j)$ 解法：同机房奆佬非出题人解法 ~~不过吊打出题人~~ $$ \begin{align} &\sum_{i=1}^n\sum_{j=1}^nlcm(a_i,a_j)\\ &=\sum 阅读全文
posted @ 2019-08-16 15:59 zmy蒟蒻 阅读(228) 评论(1) 推荐(0)
平衡树splay
摘要：splay平衡树实现 留坑 spaly权值平衡树： "普通平衡树" ~~~c++ include include include include include include include include define inf 2000000000 define rep(i,a,b) for(i 阅读全文
posted @ 2019-08-15 22:04 zmy蒟蒻 阅读(164) 评论(0) 推荐(0)
莫队
摘要：莫队的坑等有时间再填 普通莫队： "小z的袜子" ~~~c++ include include include include include include include include define inf 2000000000 define rep(i,a,b) for(int i=(a); 阅读全文
posted @ 2019-08-12 16:38 zmy蒟蒻 阅读(160) 评论(0) 推荐(1)