algorithms – Check for common element in two arrays using FFT

My task ask me to check whether there is a common element in two arrays $(x_1,x_2,…,x_n)$, $(y_1,y_2,…,y_n)$ with $x_i,y_iinmathbb{N}$ using the Fast Fourier Transform(FFT).
(I’m aware that there is a simple $O(nlog(n))$ algorithm to solve this problem using sorting and binary search.)
The tasks hints that we should consider the following product to solve the problem:
$$
prod_{i+j=n} (x_i-y_j)
$$

The product is obviously zero if there is a common element, but I am still not sure how I could compute it faster via FFT.
… I know how to use FFT to multiply polynoms efficiently, but somehow I seem to overlook something.

data – Which Is The Best Web Scraper In 2020 That Can Use A Common Man Also?

Which Is the Best Web Scraper for Data Scraping In 2020?

Many people around the world do not have enough understanding of these screen scraping tools. In their opinion, mining means extracting resources from Google or other search engines. In these days of Internet technology, the new mined resource is data. There are many data mining tools available in the market to extract specific data from the web. Every company in the world deals with tons of data, managing that data, and converting it into a useful format is a real problem for every business. If this correct information is not available in a timely manner, the company will lose valuable time in making strategic decisions about this accurate information.

Antsite Web Crawler is the best web scraping software to collect data from multiple web pages simultaneously. With this data extractor, you can download the database to spreadsheets. This tool is used in various business sectors, especially for those who create potential clients, b2b leads, set a budget to see competitors ’fees, and analyze trends online. With this web scraping tool, information is collected and used instantly for your business needs.

In this era of globalization, dealing with your important data has become a headache for many business sectors. Then Anysite Web Scraper is a profitable option for your business. Since all projects are tailored to suit the exact needs of the customer, huge savings can be made in terms of time, money and infrastructure.

testing common mark for batch files and powershell

testing common mark for batch files and powershell

echo Hello World!
Write-Host "Hello World"
echo Hello World!
Write-Host "Hello World"

object oriented – What does “common interface” mean in OOP?

I have seen the term “common interface” used a lot while reading books about OOP.

For example, the book The Essence of Object-Oriented Programming with Java and UML says the following:

Abstract classes usually define a common interface for subclasses by
specifying methods that all subclasses must override and define


My understanding of the term “common interface” is the following:

Assume that we have a superclass (or an interface or an abstract class) called Animal and two subclasses called Dog and Cat, and Animal have two virtual methods called makeSound() and move().

Now the common interface would be composed of two methods which are Animal.makeSound() and Animal.move().

Assume that we have the following code:

Animal animal1 = new Dog();
animal1.makeSound();
animal1.move();

animal1 = new Cat();
animal1.makeSound();
animal1.move();

The explanation of the above code is the following:

Animal animal1 = new Dog() creates an Animal common interface and associate a Dog object with it:

enter image description here

animal1.makeSound() sends an Animal.makeSound() message to the common interface, and then the common interface sends a Dog.makeSound() message to the Dog object:

enter image description here

Same thing happens in the case of animal1.move() (which is the Animal.move() message is sent to the common interface, etc.).

animal1 = new Cat() removes the Dog object from the common interface, and associate a Cat object with the common interface:

enter image description here

animal1.makeSound() sends an Animal.makeSound() message to the common interface, and then the common interface sends a Cat.makeSound() message to the Cat object:

enter image description here

Same thing happens in the case of animal1.move() (which is the Animal.move() message is sent to the common interface, etc.).

Am I correct in my understanding?

Why is password confirmation common in password resets and updates?

I’ve seen multiple websites with only one field for the password during registration, whereas there are two fields – Enter Password and Confirm Password – for password reset and update tasks.

Why a confirm-password is quite common in password-reset and update password?

I’ve seen multiple websites with only one field for the password during registration, whereas there are two fields password and confirm-password for password-reset and password-update pages.

authentication – Client certificate common name? Subject alternative name?

For an IoT project, I want to secure client server communication. I want both the server (Apache) and the clients identify/authenticate each other (a client won’t communicate with other clients) before clients can post some data.

There is much less information about client certificates. Besides documentations, there are best practices. I would like to know, how to set common name and subject alternative names for clients, as they won’t have a domain name and a fix IP address.

Do I simply tell the server to ignore a mismatch? Can I use a wild card only CN (CN=*)? I also would like the cert to identify specific client. Server needs to be able to tell apart client 1 from client 2, etc…

Thanks!

locus – Value of theta for which there are no common solutions (complex numbers and loci)

So there is this question that’s asking for a “range of values for theta from -pi to pi, for which arg(z-4+2i)=theta and |z+6+6i|=4 have no common solutions.” I’m not really sure how to do it as my teacher didn’t explain these sort of questions at all to us. I just don’t know where to start or what exactly to equate. Any help would be appreciated. Thanks in advance!

sony alpha – Tethering DSLR camera to PC via any common WiFi network

I am aware that it is possible to tether a camera to PC via the WiFi network that is created by the WiFi-enabled camera itself. But I want to know if it is possible to tether by connecting both camera and PC to any other common WiFi network.

Specifically, I am using Sony Alpha6400 and qDSLRDashboard as PC client for tethering. I connected the camera to my home WiFi network (to which my PC is connected). But I do not know how to go ahead. qDSLRDashboard does not seem to recognize the camera connected to same WiFi network.

Note: I have not tried this in Sony Imaging Edge. This question is specific to qDSLRDashboard.

Thank you for your answers.

dnd 5e – Can Dragonbait read or write Common, since he is able to understand it?

In D&D 5e, Tomb of Annihilation includes Dragonbait, a saurial. His stat block claims that he can understand Common but not speak it, due to the strange way in which saurials communicate.

Is there any evidence, either in 5e (which I assume is just what’s presented in Tomb of Annihilation) or anything from previous editions of D&D, that suggests that Dragonbait (whether it’s about Dragonbait specifically or saurials generally) can read or write Common, since he can apparently understand it?