teleren/devto huggingface dataset:
Apa itu Node.js ? Bagaimana Cara Kerja Node.js?
Published: 2023-09-10 06:12:42


NodeJS pertama kali diciptakan dan diperkenalkan oleh Ryan Dahl, pada tahun 2009. Node.js bukanlah sebuah bahasa pemrograman melainkan adalah sebuah platform / perangkat lunak yang didesign untuk mengembangkan aplikasi berbasis web, Bahasa yang digunakan adalah Javascript. Bila selama ini kita mengenal javascript sebagai bahasa pemrograman yang berjalan pada sisi klien / web browser saja, maka Node.js ada untuk melengkapi peran Javascript sehingga bisa berjalan pada sisi Server, seperti halnya PHP, Ruby, Perl dan sebagainya. Node.js dapat berjalan di sistem operasi Windows, Mac Os X dan linux tanpa perlu ada perubahan kode program. Node.js memiliki pustaka server HTTP sendiri sehingga memungkinkan untuk menjalankan web server tanpa menggunakan Web Server seperti Apache atau Nginx.

Untuk mengeksekusi Javascript sebagai bahasa server diperlukan engine yang cepat dan mempunyai performa yang bagus. Engine yang digunakan pada Node.js adalah engine buatan google bernama V8 yang dipakai juga pada browser Google Chrome.

## Bagaimana Node.js bekerja

Berbeda dengan bahasa pemrograman sisi server pada umumnya yang bersifat blocking, Node.js bersifat non-blocking, sebagaimana halnya javascript bekerja. Node.js berjalan dengan basis even-driver. yang dimaksud blocking secara sederhana adalah bahwa suatu kode program akan dijalankan hingga selesai, baru kemudian beralih ke kode program selanjutnya.

 

Misalkan kita memiliki algoritma pemrograman seperti berikut

- request halaman
- ambil data dari database
- tulis html berisi data
- kirim respon

Bila kita menggunakan bahasa pemrograman blocking yang bersifat Multi-threaded maka pada poin kedua saat program mengambil data dari database selama jangka waktu tertentu pada satu thread, maka thread lain yang disiapkan untuk menjalankan poin ketiga. Nah proses ketiga ini tidak akan dijalankan jika belum menerima data dari poin ketiga. Ini bukanlah masalah yang begitu besar, hanya saja Node.js dengan single-threadednya memiliki cara berbeda.
 

Node.js, mengalokasikan thread untuk setiap poin, dia hanya akan membuat thread apabila ada event yang memerlukan hal tersebut. Contohnya untuk khasus diatas, ketika program mengambil data dari database, program hanya membuat thread atau dengan kata lain mulai memproses poin ketiga apabila data dari database sudah diterima, menggunakan callback. Selain itu jika ada kode program yang tidak terkait dalam data tadi, akan dijalankan tanpa harus menunggu pengambilan data tersebut selesai.

## Kelebihan memakai Node.js

Node.js menggunakan bahasa pemrograman Javascript yang dikatakan sebagai bahasa pemrograman yang populer dan dikenal banyak orang.

Node.js dapat menangani ribuan koneksi secara bersamaan dengan penggunaan resource minimum untuk setiap prosesnya.

Node.js sangat bisa diandalkan dalam pembuatan program yang real-time.

Bagi orang yang expert dalam bahasa pemrograman javascript, Node.js sangat lebih mudah dipelajari.

Mendukung caching / penyimpanan data sementara.
Building Your Own Patient Appointment App: A Comprehensive Tutorial
Published: 2023-09-10 05:55:48

Introduction:
Embark on a journey to create a powerful Patient Appointment App from scratch. In this tutorial, we'll be using Next.js, NextAuth, Chakra UI, React Query, React Hook Form, and MongoDB to craft a seamless booking experience. And the best part? The entire project is open-source and available for free.

Why This Tutorial?
Learn by doing. Dive deep into the world of Next.js, harnessing the power of Chakra UI for stunning design, and leverage React Query and React Hook Form for smooth data management. By the end of this tutorial, you'll have a fully functional Patient Appointment App at your fingertips.

Key Features:

Seamlessly book appointments with registered doctors.
User authentication and doctor sign-up functionality.
Utilize MongoDB for robust data management.
Getting Started:
Ready to roll up your sleeves? Access the complete source code on the [GitHub repository](https://github.com/tashynw/patient-management-app), and find additional resources in the about section.

Exploring the App:
See the Patient Appointment App in action by visiting the [live demo](https://patient-appointment-app.netlify.app/). Test out the features, from booking appointments to managing your doctor profile.

Conclusion:
Building a Patient Appointment App has never been more accessible. With this tutorial, you not only acquire valuable technical skills but also have a fully functional app as a result. Embrace the freedom of open-source development and create your own appointment booking platform today!

Images:


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/3vyasupcsqr9m53nxhwl.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/6b45h3yo0k286js28b7l.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/uf8osc6eifyjhq85vyw3.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/7j8x9sp00y38irrr2dm7.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/x63oh5ky609ewos59tiq.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/c4cfitka3pg4jacdcosz.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/qjjbu46fitac8fyhpori.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/31mu4xz2x2kjmd2hzy38.png)
Navigating Waves of Information: The Caribbean Violence Web Crawler
Tags: programming, javascript, webdev, react
Published: 2023-09-10 05:48:34

Introduction:
Dive into the heart of Caribbean safety with the Caribbean Violence Tracker. Crafted with TypeScript, Node.js, and Next.js, this innovative tool scours trusted sources across the islands, delivering real-time updates on gun and violent crimes.

Empowered Insights, Informed Action:
Unleashing the potential of web crawling, our app provides instant access to vital safety data. Stay in the loop, making informed choices for your well-being.

Uniting Communities, Fostering Safety:
In times of challenge, unity is our anchor. The Caribbean Violence Tracker serves as a digital lighthouse, illuminating pathways to safety. Share insights, raise awareness, and strengthen your community.

Accessing the Caribbean Violence Tracker:
Ready to take control of your safety? Set sail with the [Caribbean Violence Tracker](https://caribbean-violence-tracker.vercel.app/) and chart a course to real-time incident updates.

Conclusion:
More than code, this is a commitment to Caribbean security. Join us on this technological voyage toward safer, more connected communities. Embrace the Caribbean Violence Web Crawler today!

Images:

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/7wmanzry6wfcwwb70q2e.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/xoovhcv1wc6agi6k0pzj.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/eeqcd48go6clhmxust45.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/26o2xith00kq4reg6vwz.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/p6wsd5mn0fesv6cye3h4.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/ptv60919o37darhvzp5q.png)
Master Python - Variables
Tags: python, beginners, codenewbie
Published: 2023-09-10 05:42:14

## Introduction
Welcome to our second part of this series mastering Python. So, in our previous lesson we have installed Python in our computer. Today, we are covering variables in Python. Without any further ado, let's get started.


### What are Variables?

Variables are like containers that store data in your Python programs. They give names to values, making it easier to work with and manipulate data. Think of variables as labeled boxes where you can put different types of information.

### Declaring Variables

In Python, declaring a variable is straightforward. You don't need to specify a data type explicitly; Python infers it for you. Here's how you declare a variable:

```python
variable_name = value
```

- `variable_name`: Choose a name for your variable (e.g., `age`, `name`, `score`). Follow Python naming conventions: use letters, numbers, and underscores, and start with a letter.
- `=`: The equal sign is used for assignment, meaning you're giving a value to your variable.
- `value`: This can be any data type (e.g., numbers, strings, lists, or even other variables).

### Variable Types

Python supports various data types for variables. Here are a few common ones:

1. **Integers (`int`):** Used for whole numbers, e.g., `age = 25`.

2. **Floats (`float`):** Used for decimal numbers, e.g., `price = 19.99`.

3. **Strings (`str`):** Used for text, e.g., `name = "Alice"`.

4. **Booleans (`bool`):** Used for True/False values, e.g., `is_student = True`.

### Using Variables

Once you've declared variables, you can use them in your code. Here are some common operations:

1. **Printing Variables:**

   ```python
   print(variable_name)
   ```

   This displays the value of the variable in the console.

2. **Performing Operations:**

   You can perform various operations on variables, such as mathematical calculations.

   ```python
   x = 5
   y = 3
   sum = x + y
   ```

3. **Updating Variables:**

   You can change the value of a variable by reassigning it.

   ```python
   age = 25
   age = age + 1  # Increment age by 1
   ```

### Variable Naming Tips

- Choose descriptive names: Make your variable names meaningful, so your code is easy to understand.
- Use lowercase letters: Variable names are typically written in lowercase, with words separated by underscores (e.g., `user_name`).
- Avoid using Python reserved words (e.g., `if`, `else`, `while`) as variable names.

### Conclusion

Understanding variables is a crucial step in your journey to mastering Python. They allow you to store and manipulate data, making your code more dynamic and powerful. Practice using variables in different contexts to become more proficient in Python programming. As you progress, you'll discover that variables are the building blocks of more complex programs and algorithms.
AI-Powered Quiz Generation: Introducing QwizLab with NextJS
Tags: openai, chatgpt, webdev, programming
Published: 2023-09-10 05:39:20

Discover QwizLab, a NextJS app that leverages the power of AI to transform your notes into quizzes. Say goodbye to manual quiz creation and hello to a smarter, more efficient learning experience.

Unleashing the AI Advantage:
QwizLab harnesses OpenAI's capabilities to automatically generate quizzes from your notes. Dive into your studies without the hassle of crafting questions.

Total Control, Effortless Editing:
Take charge of your quizzes. With QwizLab, you can create, edit, and delete questions with ease, ensuring your quizzes are perfectly tailored.

Export and Share:
Need to collaborate or study offline? QwizLab lets you export quizzes effortlessly, making sharing and studying with peers a breeze.

Get Started:
Join the future of learning. Visit QwizLab [here](https://qwizlab.com/) and sign up!

Conclusion:
QwizLab is your shortcut to smarter studying. Embrace the power of AI for a more effective learning journey. Try QwizLab today!

Images:

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/8vgads79mrcgkuc7yu1t.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/okubulc9iizrlvr11fh3.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/fg1z7tmvzybd1ln80rir.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/wtr292snibmjmfpy2lfo.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/pupw9m282ahty7umxf50.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/rguihdq4q1w67tc3ip83.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/yyepips05wirzpyyue49.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/20lrbyj2zzb79wpxro01.png)
Solving the "Trapping Rain Water" Problem on Leet Code
Tags: java, coding, programming, discuss
Published: 2023-09-10 05:35:23

## Question

## 42. Trapping Rain Water
**Type:** Hard
**Liked by:** 29K
**Disliked by:** 412

**Companies that asked this Question**
_Companies: No of times Asked_

Amazon 14
Bloomberg 5
Adobe 4
Apple 4
Goldman Sachs 3
Yandex 3
EPAM Systems 2
Microsoft 16
Google 9
Uber 4
MakeMyTrip 3
Facebook 2
eBay 2
Salesforce 2
Intel 8
Rubrik 8
Qualtrics 7
Tesla 6
Oracle 5
Citadel 5
VMware 4
C3 IoT 4
Snapchat 3
Lyft 3
Visa 3
PayPal 3
ServiceNow 3
Swiggy 3
National Instruments 3
Sapient 3
Zoho 2
Intuit 2
Coupang 2
Yahoo 2
Expedia 2
Twitch 2
Morgan Stanley 2
DE Shaw 2
TikTok 2
Navi 2
Airbnb 1 
Zenefits 1
Twitter 1
Wix 1


Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it can trap after raining.

![Rainwater Image](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/b5lho9om9ah85sozyxtw.png)

**Example 1:**
Input: height = `[0,1,0,2,1,0,1,3,2,1,2,1]`
Output: `6`

Explanation: The above elevation map (black section) is represented by array [0,1,0,2,1,0,1,3,2,1,2,1]. In this case, 6 units of rainwater (blue section) are being trapped.

**Example 2:**
Input: height = `[4,2,0,3,2,5]`
Output: `9`
 
**Constraints:**
`n == height.length
1 <= n <= 2 * 104
0 <= height[i] <= 105`

## Intuition:

The goal is to calculate the total trapped water between bars with given heights. We achieve this by computing left and right boundaries for each bar and then calculating trapped water based on these boundaries.

## Approach:

- Initialize res to 0, lb (left boundaries), and rb (right boundaries) arrays.
- Calculate left boundaries (lb) and right boundaries (rb) for each bar in the input array.
- Iterate through the input array, calculating trapped water for each bar and accumulating it in res.
- Return res as the total trapped water.

## Complexity:

**Time complexity:** O(n) where n is the number of elements in the input array.

**Space complexity:** O(n) due to the lb and rb arrays used to store boundaries.

## Code:

```
class Solution {
    public int trap(int[] height) {
        int  res = 0;
        int[] lb = new int[height.length];
        int[] rb = new int[height.length];

        lb[0] = height[0];
        for(int i = 1 ; i < height.length -1 ;i++){
            lb[i] = Math.max(height[i],lb[i-1]);
        }

        rb[height.length - 1] = height[height.length - 1 ];
        for(int i = height.length - 2 ; i >= 0;i--){
            rb[i] = Math.max(height[i],rb[i+1]);
        }

        for(int i = 1 ; i < height.length -1 ; i++){
            int tw = Math.min(lb[i],rb[i]) - height[i];
            res = res + tw;
        }

        return res;
    }
}
```

Happy coding,
shiva
Default Arguments - HackerRank Solution Python
Tags: python, algorithms, beginners, programming
Published: 2023-09-10 05:31:00

Default arguments are a feature of many programming languages that allow you to specify a value for an argument that is not explicitly provided by the caller. This can be useful for making your code more concise and reusable.

## Problem Statement and Explanation

Python supports a useful concept of default argument values. For each keyword argument of a function, we can assign a default value which is going to be used as the value of said argument if the function is called without it.

## Default Arguments Solution in Python
{% gist https://gist.github.com/codeperfectplus/2ece78a078accff5f2f8dbfa7cc2ff07.js %}

## Explanation of Solution

- The code you have given defines two classes, `EvenStream` and `OddStream`. Each class has a method called `get_next`() which returns the next even or odd number, respectively. The function `print_from_stream`() takes an integer n as input and prints the first n even or odd numbers, depending on the value of the stream parameter.

- The main function first reads the number of queries from the user. Then, it loops over the queries. In each iteration, it reads the name of the stream and the number of numbers to print from the user. It then calls the `print_from_stream`() function, passing the number of numbers to print and the appropriate stream object.

For example, if the user enters the following input:

- `even 5`

then the main function will call the `print_from_stream`() function with the following arguments:

- `n = 5` and `stream = EvenStream()` and the `print_from_stream`() function will print the first 5 even numbers.

`0 2 4 6 and 8`

_The problem statement is taken from [Hackerrank](https://www.hackerrank.com/domains/python), and the solutions are implemented by the **CodePerfectPlus** team_

{% post https://dev.to/codeperfectplus/reverse-integer-algorithm-in-c-java-and-python-leetcode-problem-2hb9 %}

## Other Article By Author

- [HackerRank Solve Python Algorithm Series](https://codeperfectplus.com/category/Solve-python)
- [HackerRank Problem Solving Algorithm Series](https://codeperfectplus.com/category/Problem-solving)
- [30 Days of Code HackerRank](https://codeperfectplus.com/category/Hackerank-30-days-of-code)
- [10 Days of JavaScript HackerRank](https://codeperfectplus.com/category/10-days-of-javascript)

### [30 Days of Code SubReddit](https://www.reddit.com/r/30daysofcode)
Master Python - Installation
Tags: python, codenewbie, beginners, programming
Published: 2023-09-10 05:14:28

## Introduction
In this blog article. We are going to have a brief introduction on Python and Programming. So, without any further ado, let’s get started into a brief introduction of Python.

## What is Python?
Python is an interpreted, mutli paradigm and general-purpose scripting language. It is a popular programming language for beginners due to its readability of code. It is used in many domains of Computer Science like Data Science, Machine Learning and so on. Before we get started writing our Python code, we need to install Python into our computer.

## Installing Python
To install Python,

Head over to Python website.
Click on Downloads and Click on “Python 3.XX.X”.
Follow the instructions of the setup and install Python.
Congrats, you have installed Python. To verify our installation, Open Command Prompt (or Terminal if you are on macOS.) and type:

`python --version` or `python3 --version` if you are on macOS and press Enter.

You can see the output is the version of Python that you have installed.
Alright, we have installed Python. So, let’s start writing Python code.

Writing our First Line of Python
Let’s write our line of Python Code. So,

Open your Command Prompt or terminal if you are on macOS.
Type python or python3 if you are on macOS and press Enter.
Then type `print('Hello Python!')`.
As you can see, we get `Hello Python!`. This is a Python REPL(Read-Eval-Print-Loop)

## Conclusion
We have learnt:

- A Brief Introduction of Python
- How to install it?
- Writing our First Line of Python
✨Cập Nhật Link Đăng Ký Tài Khoản 789club
Tags: 789club, 789clubasia, nhacai789club, linkđăngký
Published: 2023-09-10 04:49:12

[✨Cập Nhật Link Đăng Ký Tài Khoản 789club](https://789club.asia/huong-dan-dang-ky-789club/)
✨Hướng dẫn đăng ký tài khoản 789club
✨Nhà cái uy tín- cá cược hấp dẫn
✨Cổng game cá cược đỉnh cao- khuyến mãi hấp dẫn
✨Trả thưởng cao- bảo mật cao
👇chi tiết 👇
🌐Website: [https://789club.asia/huong-dan-dang-ky-789club/](https://789club.asia/huong-dan-dang-ky-789club/)
🌐fapage: [https://www.facebook.com/789Clubasia](https://www.facebook.com/789Clubasia)
📧Email: [[789clubasia@gmail.com](789clubasia@gmail.com))
☎️Sdt: 0563 102 907
📌Địa chỉ: 14 Ngõ 9/14 Minh Khai, Trương Định, Hai Bà Trưng, Hà Nội, Việt Nam
#789Club #789Clubasia #nhacai789Club #linknhacai #linkđăngký #linkkhuyenmai
Tree Service Belleville IL
Published: 2023-09-10 03:05:46

Welcome to our [Tree Service Company in Belleville, Illinois!](https://bellevilleiltreeservice.com/) We are a team of experienced and skilled professionals dedicated to providing top-notch tree care services to our clients. Our mission is to ensure that your trees are healthy, safe, and beautiful, while also enhancing the value and beauty of your property.

We offer a wide range of tree care services, including tree trimming, pruning, removal, stump grinding, and emergency tree services. Whether you need routine maintenance, hazard assessments, or storm damage cleanup, our team is here to help.

As the best tree service provider to hire in Belleville, IL, we are committed to using the latest techniques and equipment to deliver exceptional results. We understand the importance of safety, and we always follow industry best practices to ensure that your property and our team are protected during the tree care process.

Tree Service Belleville IL
23 N 11th St Belleville, IL 62220, USA (Illinois)
6182495321
[https://bellevilleiltreeservice.com/](https://bellevilleiltreeservice.com/)
MorseEncoder: Arduino Library for Encoding Data to Morse Code (Audio & Light)
Tags: webdev, arduino, morse, cpp
Published: 2023-09-10 03:31:28

Hi, My name is Ashen a software developer. I am always passionate about cryptography algorithms and microcontrollers. so I made something that combines two.
its a Library for Arduino called [MorseEncoder](https://github.com/ktauchathuranga/MorseEncoder) and what it do is when you pass data to it its going to convert it to Morse code and broadcast it.
it supports various data types to Morse codes, including integers, longs, characters, character arrays, and strings.
its very well documented including installation guides in the repo and a example will look like this,
```cpp
#include "MorseEncoder.h"

MorseEncoder morseA(9);       // Initialize with the desired pin for Audio **PWM pins only
MorseEncoder morseL(13);      // Initialize with the desired pin for Light

void setup() {
  morseA.beginAudio(15, 500); // [AUDIO] Initialize WPM (word per minute) rate and frequency
  morseL.beginLight(15);      // [LIGHT] Initialize WPM (word per minute) rate
}

void loop() {
  String message = "sos";
  morseA.print(message);   // [AUDIO] Boradcast encoded audio
  delay(2000);
  morseL.print(message);   // [LIGHT] Broadcast encoded light
  delay(2000);
}
```

in that example I used both features and so you can easily understand how the library works.

---
Here is a little YouTube short video that ive made with my library, if you know what that Morse code says, comment down bellow 😉

{% embed https://www.youtube.com/watch?v=UVtpgKzgM74 %}
88 berufliches Vorwärtskommen: Geld – Ein Elefant im Raum Deutschland.
Tags: deutsch, career, motivation, discuss
Published: 2023-09-10 03:30:00

Moin Moin,

„über Geld spricht man doch nicht“. Eine wohl bekannte Redewendung. Während man über Geld nicht spricht, sei es um seine Privatsphäre zu schützen, andere nicht zu kränken oder Neid zu vermeiden, verbringt man viel Zeit mit dem Geld verdienen und ausgeben – direkt oder indirekt. Es scheint mir ein interessantes Phänomen, ein Elefant im Zimmer, dass hierzulande ( Deutschland (1)) die Auffassung verbreitet ist, dass man über Geld nicht spricht, während man viel Zeit, bezüglich Geld, aufwendet.

Man spricht auch in der Schule im Allgemeinen nicht über Geld. Dies führt dazu, dass man sich bei Anliegen wie Gehaltsverhandlungen oder Stundensätzen, Altersvorsorge usw., selbst verlässliches Wissen und verlässliche Kenntnisse aneignen muss. Stellen wir uns mal vor der Fremdsprachenunterricht in der Schule wäre so aufgebaut, bzw. den gäbe es nicht oder den Matheunterricht. Alles lebensrelevante Angelegenheiten möchte ich meinen.


Sprichst du über Geld?

Interessant auch:
[Stern.de – Abschnitt „Niemand schweigt so viel über Geld wie wir“↗](https://www.stern.de/neon/vorankommen/finanzen/ueber-geld-wird-nicht-gesprochen---aber-wieso-eigentlich-nicht--8495782.html)


Lass uns mittels Kommentaren austauschen.

Beste Grüße,
Mustafa

Oder auch mittels E-Mail: mustafa.kevin.dwenger@posteo.de
Betreff: Austausch

(1) In Österreich, der Schweiz, Liechtenstein und Luxemburg ebenfalls?