Yes, JavaScript is commonly allowed in coding interviews, especially for web development roles. It supports all essential data structures and algorithms, making it suitable for solving various problems. Its straightforward syntax helps you write clean code efficiently, which is beneficial during time-constrained interviews.
Grokking the Coding Interview Patterns in JavaScript
The ultimate guide to coding interviews in JavaScript. Developed by FAANG engineers. Learn essential patterns, practice with real-world questions, and get interview-ready in just a few hours.
Fahim ul Haq is the co-founder and CEO of Educative, a hands-on learning platform for software engineers. He spent nearly a decade as a software engineer at Microsoft and Meta, where he gained deep experience building large-scale distributed systems. His work spanned Project Red Dog at Microsoft, which evolved into Microsoft Azure, and Scuba, Meta's real-time data analytics engine. In 2015, Fahim co-founded Educative to help developers get hands-on with new skills. Fahim's courses have helped hundreds of thousands of engineers learn System Design and prepare for technical interviews. Fahim earned his M.S. in Computer Science from the University of Washington in 2015.
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What You'll Learn
- Understand the essential patterns behind common coding interview questions — without having to drill endless problem sets
- Identify the underlying pattern of each interview question by assessing the problem statement (and learn the tricks required to solve it)
- Practice your skills in a hands-on, setup-free coding environment
- Learn to efficiently evaluate the tradeoffs between time and space complexity in different solutions
- Develop a flexible conceptual framework for solving any question, by connecting problem characteristics, solution techniques, and coding design patterns
Learning Roadmap
Two Pointers
The Two Pointers pattern uses two coordinated pointers or iterators to traverse data efficiently.
Fast and Slow Pointers
The Fast and Slow Pointers pattern uses two pointers that traverse a data structure at different speeds.
Sliding Window
Uses a window, either fixed or dynamic, to optimize the analysis of sequential data (substring or subarray) through iterative processing, minimizing the need for nested loops.
Intervals
The Intervals pattern is a powerful algorithmic technique for solving problems involving ranges of values, such as time spans or numeric ranges.
In-Place Manipulation of a Linked List
In-place manipulation of a linked list refers to modifying the linked list directly by changing the pointers between existing nodes, without creating a new linked list or using extra data structures.
Two Heaps
A heap is a specific data structure with a fixed ordering (min or max), while a priority queue is an abstract data type that handles custom priority requirements for elements.
K-way Merge
The K-Way Merge pattern is an algorithmic strategy used to efficiently combine multiple sorted sequences into a single sorted result.
Top K Elements
The Top K Elements pattern focuses on efficiently identifying the k largest, smallest, or most frequent elements in a dataset.
Modified Binary Search
It applies a binary search technique with variations to efficiently solve problems like finding specific targets, peaks (first/last occurrence), or rotated array elements by reducing the search space.
Subsets
The Subsets pattern is an algorithmic strategy used to generate all possible combinations or subsets of a given set of elements.
Greedy Techniques
Makes locally optimal choices at each step, aiming for a globally optimal solution in problem-solving scenarios, often without reassessment.
Backtracking
Systematically explores all possibilities to find solutions, often used in problems with multiple decision points, exploring, and undoing choices.
Dynamic Programming
Solves complex problems by breaking them into smaller overlapping subproblems and storing results to avoid redundant computations, optimizing time and space.
Cyclic Sort
Sorts an array of integers from 1 to n in place by repeatedly swapping the elements until each is placed in its correct position.
Topological Sort
Determines a valid linear ordering of nodes in a directed acyclic graph that has dependencies on each other, crucial in tasks like scheduling or dependency resolution.
Sort and Search
Combines sorting and searching techniques to effectively process and retrieve data, often using sorting algorithms and binary search to optimize problem-solving in datasets that can be ordered.
Matrices
Organizes data in a two-dimensional grid format, where each element is accessed by its row and column, enabling structured manipulation and traversal of the data.
Stacks
Operates on a last-in, first-out principle, where elements are added and removed from the same end, facilitating ordered data processing and retrieval.
Graphs
Represents a set of connected nodes or vertices, allowing for traversal and analysis of relationships or connections between data points.
Tree Depth-First Search
Traverses a tree by exploring as deeply as possible along each branch before backtracking, which is useful for tasks like traversal, pathfinding, or search operations.
Tree Breadth-First Search
Explores nodes of a tree level by level, ensuring each level is processed before moving to the next, often using a queue to manage traversal.
Trie
Organizes data in a tree structure where each node represents a character, enabling efficient insertion, deletion, and search operations for words.
Hash Maps
Utilizes a data structure that maps keys to values, enabling efficient insertion, deletion, and retrieval operations for associative arrays.
Knowing What to Track
The Knowing What to Track pattern focuses on identifying and maintaining only the key variables or states necessary to solve a problem efficiently, such as counts, indices, or states.
Union Find
Maintains disjoint sets, supporting operations to determine the set to which an element belongs (find) and merge two sets (union).
Custom Data Structures
Designs specialized structures tailored to specific problem requirements, optimizing data representation and operations for efficient solutions.
Bitwise Manipulation
It uses binary operations to efficiently perform calculations, comparisons, or transformations directly on bits, optimizing for low-level data control.
Math and Geometry
Applies mathematical concepts and geometric properties to solve problems efficiently, often involving calculations, number properties, coordinate geometry, or transformations.
Challenge Yourself
Test your understanding of various coding challenges focusing on algorithm efficiency.
Monotonic Stack
The Monotonic Stack pattern uses a stack that maintains elements in increasing or decreasing order to efficiently find the next or previous greater or smaller element.
Course Author:
Fahim ul Haq
Software Engineer, Distributed Storage at Meta and Microsoft, Educative (Co-founder & CEO)
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Frequently Asked Questions
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