[BZOJ3834][Poi2014]Solar Panels Description Having decided to invest in renewable energy, Byteasar started a solar panels factory. It appears that he has hit the gold as within a few days  clients walked through his door. Each client has ordered a si…

题目描述 Having decided to invest in renewable energy, Byteasar started a solar panels factory. It appears that he has hit the gold as within a few days  clients walked through his door. Each client has ordered a single rectangular panel with specified w…

题目链接 BZOJ3834 题解 容易想到对于\(gcd(x,y) = D\),\(d\)的倍数一定存在于两个区间中 换言之 \[\lfloor \frac{a - 1}{D} \rfloor < \lfloor \frac{b}{D} \rfloor\] \[\lfloor \frac{c - 1}{D} \rfloor < \lfloor \frac{d}{D} \rfloor\] 整除分块即可做到\(O(n\sqrt{max\{b\}})\) #include<algorithm&…

问题相当于找到一个最大的k满足在$[x_1,x_2]$,$[y_1,y_2]$中都有k的倍数 等价于$\frac{x_2}{k}>\frac{x_1-1}{k}$且$\frac{y_2}{k}>\frac{y_1-1}{k}$ 注意到这只有$O(\sqrt{n})$种取值,于是可以分段计算,做到$O(\sqrt{n})$每次询问 #include<cstdio> int T,a,b,c,d,i,j,t; inline void up(int&a,int b){if(a>…

3834: [Poi2014]Solar Panels Time Limit: 20 Sec  Memory Limit: 128 MBSubmit: 367  Solved: 285[Submit][Status][Discuss] Description Having decided to invest in renewable energy, Byteasar started a solar panels factory. It appears that he has hit the go…

题目描述 Having decided to invest in renewable energy, Byteasar started a solar panels factory. It appears that he has hit the gold as within a few days  clients walked through his door. Each client has ordered a single rectangular panel with specified w…

http://www.lydsy.com/JudgeOnline/problem.php?id=3834 题意:求$max\{(i,j)\}, smin<=i<=smax, wmin<=i<=wmax$,其中$smin<=smax<=10^9, wmin<=wmax<=10^9$,有$N<=1000$组数据 #include <bits/stdc++.h> using namespace std; int main() { int cs,…

题目大意: $T(T\le1000)$组询问,每次给出$A,B,C,D(A,B,C,D\le10^9)$,求满足$A\le x\le B,C\le y\le D$的最大的$\gcd(x,y)$. 思路: 令$n=\gcd(x,y)$,则若$n$为合法的答案,当且仅当$\lfloor\frac{A-1}n\rfloor<\lfloor\frac Bn\rfloor,\lfloor\frac{C-1}n\rfloor<\lfloor\frac Dn\rfloor$. 考虑数论分块,每次用块内最大值…

题意 给出一个序列,在线询问区间众数.如果众数有多个,输出最小的那个. 题解 这是一道分块模板题. 一个询问的区间的众数,可能是中间"整块"区间的众数,也可能是左右两侧零散的数中的任意一个.为了\(O(\sqrt n)\)求出究竟是哪一个,我们需要在一次对两侧零散点的扫描之后\(O(1)\)求出被扫数在区间内的的出现次数. 所以需要预处理的有: cnt[i][j]: i在前j块中出现的次数 mode[i][j]: 第i块到第j块组成的大区间的众数 #include <cstdio…

Luogu 2801 教主的魔法 | 分块模板题 我犯的错误: 有一处l打成了1,还看不出来-- 缩小块大小De完bug后忘了把块大小改回去就提交--还以为自己一定能A了-- #include <cstdio> #include <cstring> #include <algorithm> #include <set> using namespace std; typedef long long ll; #define space putchar(' ')…