JavaScript Exercises

Train your mind to think in JavaScript. This practice track is built for developers who want to boost their coding fluency and prepare for interviews by practicing real-world JavaScript problems.

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Overview

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When it comes to technical interviews, JavaScript fluency isn’t just about knowing the syntax—it’s about solving problems fast, cleanly, and confidently. This practice will help you build that fluency through repeated exposure to JavaScript problem-solving patterns that mirror what real interviews expect. You’ll cover core data structures and patterns using JavaScript: arrays, objects, recursion, two pointers, sliding windows, maps, and more. Each practice challenge is designed to push your understanding of how JavaScript behaves behind the scenes—from hoisting and closures to async execution patterns and functional problem solving. With instant feedback, targeted hints, and guided solutions, this track is designed to help you drill deliberately, revisit patterns, and solve multiple problems tied to the same core pattern. It will help you recognize structure and think faster with each attempt.

When it comes to technical interviews, JavaScript fluency isn’t just about knowing the syntax—it’s about solving problems fast, ...Show More

WHAT YOU'LL LEARN

How to solve JavaScript problems the way top interviewers expect—using patterns, structure, and clean syntax.

How to handle common interview challenges like closures, hoisting, and asynchronous execution.

Structured challenge sets that reinforce essential JavaScript concepts through repetition and pattern recognition.

Core practice in real-world structures: arrays, objects, maps, sets, stacks, queues.

Confidence in writing and debugging JavaScript code under timed conditions.

Strategies for writing efficient, readable code using ES6+ features.

How to solve JavaScript problems the way top interviewers expect—using patterns, structure, and clean syntax.

JavaScript Challenges with PAL

Question

Difficulty

Solution

Minimum Window Substring

Easy

Link

Developed by MAANG Engineers

Every Educative lesson is designed by a team of ex-MAANG software engineers and PhD computer science educators, and developed in consultation with developers and data scientists working at Meta, Google, and more. Our mission is to get you hands-on with the necessary skills to stay ahead in a constantly changing industry. No video, no fluff. Just interactive, project-based learning with personalized feedback that adapts to your goals and experience.

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Skip the LeetCode grind with a custom roadmap that adapts to your goals. Hands-on practice for Coding Interviews, System Design, and more.

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Evaluate and debug your code with the click of a button. Get real-time feedback on test cases, including time and space complexity of your solutions.

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AI Code Mentor

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