# Algorithm Problem Solving: Two-Sum and Three-Sum Problem

UPDATE : The Article currently contains Brute-Force Approaches for Three-sum Problem, Will update the better approaches soon.

I have started exploring Advent of Code for the year 2020. For Day 1, The scenario included writing a program to find the product of ’n’ numbers that add up to the given target sum value. So, Ideally finding those two/three elements is the key. This Article explains various ways you can achieve this.

# Problem Statement for Two sum Problem

For example, suppose your sample input contained the following…

# Introduction to Node.js

Node.js is an open source, cross-platform, asynchronous event-driven JavaScript runtime. Node.js can be used to write command line tools and server-side scripts outside of a browser. It is designed to build scalable network applications. You need to use JavaScript programming language to code in Node.js.

# How to install ?

Approach 1 :

The first approach to install Node.js is simple and straight forward. You must visit The official Node.js website and follow the installation instructions here : https://nodejs.org

Approach 2 :

Alternatively, if you are interested in installing…

# Building CRUD APIs using Deno and oak

Deno is fairly new environment compared to Node. One of the first thing that a developer would want to do while learning Deno is to build CRUD api’s. Deno has several several projects which help us achieve this namely, deno-express, oak, servest, deno-drash,and pogo. In this article we will learn about building a todo list using Deno and Oak.

## What are we building?

Oak is project that has been inspired by Koa, a popular Node.js HTTP middle-ware framework. We will use oak and Deno to build a small application which will deal with todos list. …

# Creating your first local server using Deno

Deno is a secure runtime for JavaScript and TypeScript. It aims to provide a productive and secure scripting environment for the modern programmer. It is built on top of V8, Rust, and TypeScript. It was created to address several shortcomings of Node JS namely,

· Make use of promises in a better way.

· The usage of Build System — GYP

· Usage of package.json and node_modules to allow to store all node_modules and their sub-modules rather than absolute import…

# Introduction to Dynamic Programming — Memoization

Dynamic Programming simply means optimization of your code over plain recursion. The idea is to store the results of sub-problem and reuse it later when needed to do same calculations.

Let’s see how Dynamic Programming makes its program more efficient by using Memoization. We will write finding “n-th” Fibonacci Number programme to achieve this.

Fibonacci Problem — General Approach

Following diagram shows the general way most of us approach solving Fibonacci Number Problem. Here we have a function fib(n) which accept a parameter “n” and gives the output of n-th element in fibonacci series.

# Pre-requisites

2. Node installed in your machine.
3. Login to npm using command prompt using one of the following commands, you will be prompted with usename, password and email address.

`npm adduser` or `npm login`

# Creating a simple package

`mkdir logger-app`

`cd logger-app`

`npm init -y`

`npm i chalk`

Create a file called index.js and copy the following content.

`const chalk = require('chalk');class Log {    info({ msg = "", data = "" }) {        console.log(`"\${chalk.green(msg)}", "\${data}" was posted on "\${Date()}" with status \${chalk.green('✓')}`)    }…`

# Create a React application from scratch using webpack, babel and React

This article helps in understanding how the “create-react-app” command works behind the scene. You can build a react application from the scratch using webpack, babel and react libraries.

Steps that you should follow to build a React application from scratch.

Open the command prompt and start executing the following commands sequentially.

1. mkdir webpack-bolier-plate

2. cd webpack-bolier-plate

3. npm init -y

4. npm install react react-dom react-hot-loader

5. npm install — save-dev webpack webpack-cli @babel/preset-react babel-loader @babel/core @babel/preset-env @hot-loader/react-dom webpack-dev-server

## Manipulation of Files.

1. Now create a file named webpack.config.js and copy the following content in it.
`const webpack = require('webpack');const path = require('path');const…`

# How to host a React app on Azure

Azure App Service is a PaaS that allows you to host web, mobile apps, web API’s and logic apps.This article explains about how to host your react app on azure app service. Assuming you have npm and VS Code installed in your machine, follow below steps sequentially.

1. Open VS Code terminal.

2. Create a react app by running ‘npx create-react-app my-app‘ command.

3. The folder structure of the app should look like this.

## Kailas Walldoddi

Fullstack Developer. Loves to write about Javascript, React.js, Node.js , Cloud Platforms.

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