题目 Source http://hihocoder.com/problemset/problem/1388 Description Profess X is an expert in signal processing. He has a device which can send a particular 1 second signal repeatedly. The signal is A0 ... An-1 under n Hz sampling. One day, the device…

FFT 就可以了 比赛时候没时间做了 #include<bits/stdc++.h> using namespace std; typedef long long ll; const int INF = 0x3f3f3f3f; const int MAXN = 6e4+5; int A[MAXN<<2], B[MAXN<<2], C[MAXN<<2]; struct FFTSOLVE { int pos[MAXN<<2]; struct comp…

传送门:hihocoder #1388 : Periodic Signal 先来几个大牛传送门:  (模板) NTT long long 版 解法一:因为我们知道FFT会精度不够,所以坚持用NTT,但是模数不够大,然后就一直GG,看来我们的搜索姿势也有问题,居然没有搜到上面大神的板子,真的是GG http://www.cnblogs.com/WABoss/p/5903927.html /*******************************************************…

#1388 : Periodic Signal 时间限制:5000ms 单点时限:5000ms 内存限制:256MB 描述 Profess X is an expert in signal processing. He has a device which can send a particular 1 second signal repeatedly. The signal is A0 ... An-1 under n Hz sampling. One day, the device fell…

题目链接: https://hihocoder.com/problemset/problem/1388 Periodic Signal 时间限制:5000ms内存限制:256MB 问题描述 Profess X is an expert in signal processing. He has a device which can send a particular 1 second signal repeatedly. The signal is A0 ... An-1 under n Hz s…

#1388 : Periodic Signal   描述 Profess X is an expert in signal processing. He has a device which can send a particular 1 second signal repeatedly. The signal is A0 ... An-1 under n Hz sampling. One day, the device fell on the ground accidentally. Prof…

时间限制:5000ms 单点时限:5000ms 内存限制:256MB 描述 Profess X is an expert in signal processing. He has a device which can send a particular 1 second signal repeatedly. The signal is A0 ... An-1 under n Hz sampling. One day, the device fell on the ground accidenta…

题目链接:http://hihocoder.com/problemset/problem/1388?sid=974337 题目大意:找出一个$k$,使得$\sum_{i=0}^{n-1}(A_{i}-B_{i+k \quad mod \quad n})^{2}$最小 把那个式子拆开..得到: $\sum _{i=0}^{n-1} A_{i}^{2}+\sum_{i=0}^{n-1}B_{i}^{2}-\sum_{i=0}^{n-1}2*A_{i}*B_{i+k}$ 前面的两个和式是定值,所以最小…

[题目链接] http://hihocoder.com/problemset/problem/1388 [题目大意] 给出A数列和B数列,求下图式子: [题解] 我们将多项式拆开,我们可以得到固定项A2和B2,以及变动项-2AB,所以现在只要最大化AB即可.我们发现将A序列倒置,B序列倍置,所得到的卷积序列中的最大值就是AB的最大值,但是考虑到精度问题,我们在所得到的卷积序列中只判断极值产生的位置而不是直接获得极值,最后我们从极值产生的位置直接计算答案即可. [代码] #include <cst…

NTT (long long 版) #include <algorithm> #include <cstring> #include <string.h> #include <iostream> #include <list> #include <map> #include <set> #include <stack> #include <string> #include <utility&g…