Essential Concepts in JavaScript, React, and Algorithms

 

Understanding React Custom Hooks

Custom hooks in React allow you to reuse stateful logic across multiple components. By creating a function that starts with "use", you can encapsulate logic like fetching data or managing form inputs, improving code reusability and readability .

Setting Cookies in JavaScript

JavaScript allows setting cookies using document.cookie. However, this method has limitations, so using Set-Cookie in the HTTP header or libraries like js-cookie ensures better control over expiration, path, and security settings javascript singleton .

Using Regular Expressions in JavaScript

Regular expressions (RegEx) help in pattern matching and text validation. JavaScript provides the RegExp object and methods like .test() and .match() to work with RegEx efficiently, enabling tasks like email validation and string replacement.

Implementing the Singleton Pattern in JavaScript

A singleton ensures that only one instance of a class exists throughout the application. In JavaScript, this can be implemented using a closure or a class with a static instance, ensuring shared data consistency across modules.

What is React.js?

React.js is a JavaScript library for building dynamic user interfaces. Developed by Facebook, it uses a component-based structure, Virtual DOM for efficiency, and supports declarative programming, making UI development more manageable and performant.

Understanding the Greedy Algorithm

A greedy algorithm makes the most optimal choice at each step, aiming for a globally optimal solution. Common examples include Huffman Coding, Prim’s Algorithm, and Fractional Knapsack, which benefit from this approach.

Call, Apply, and Bind in JavaScript

These methods help control the execution context (this) of functions:

call() invokes a function with a specified this value and arguments passed individually.

apply() is similar but takes arguments as an array.

bind() returns a new function with the specified this value, allowing later execution.

What is Backtracking?

Backtracking is an algorithmic technique used for solving problems recursively by exploring all possibilities. It is commonly applied in N-Queens, Sudoku Solver, and Graph Coloring, where it backtracks upon encountering a failure.

Dijkstra’s Algorithm in Data Structures

Dijkstra’s algorithm finds the shortest path from a single source node to all other nodes in a weighted graph. It uses a priority queue to explore the smallest known distance, making it efficient for routing and network optimization.

Fractional Knapsack Problem

The fractional knapsack problem allows breaking items into fractions to maximize total value. It uses a greedy approach by prioritizing items with the highest value-to-weight ratio, ensuring an optimal solution compared to the 0/1 knapsack problem.