Java DSA: LEETCODE Exercises — Linked Lists, Stacks & Queues

Java DSA: LEETCODE Exercises — Linked Lists, Stacks & Queues by Interview Practice Academy is a hands‑on Udemy course that lets you master high‑frequency interview problems in 2026. Whether you search for a free Java DSA course, an online Java data‑structures Udemy course, or want to learn linked lists, stacks and queues online, this training delivers production‑grade Java implementations, Big‑O analysis, and a certificate of completion. Updated July 2026, the curriculum focuses on the exact patterns asked by FAANG/MAANG technical screens, giving you practical skills that translate directly into interview success.

What You'll Learn

• Build custom Linked List, Stack, and Queue classes from scratch using idiomatic Java.
• Master two‑pointer and slow/fast mechanics to detect cycles, find middle nodes, and compute list intersections in O(N) time.
• Learn in‑place node manipulations such as reversal, partitioning, and reordering without extra memory allocation.
• Understand monotonic stack and queue patterns to solve Next Greater Element, Daily Temperatures, and Sliding Window Maximum problems.
• Create robust Java Collections Framework (JCF) solutions, selecting the optimal LinkedList, ArrayDeque, or PriorityQueue for each scenario.
• Implement expression evaluators, call‑stack simulations, and task schedulers using stack‑based algorithms.
• Apply rigorous time‑ and space‑complexity analysis to every solution, guaranteeing O(N) performance and O(1) auxiliary space where possible.
• Analyze memory and reference allocation in Java, explaining garbage‑collection behavior and avoiding common pitfalls like memory leaks.

Course Details

• Instructor: Interview Practice Academy
• Rating: N/A
• Duration: N/A
• Level: Not specified
• Language: en‑US
• Enrolled students: 41,322
• Last updated: Not specified
• Certificate: Yes, upon completion
• Includes: Lifetime access, mobile‑friendly videos, self‑paced learning

What This Course Covers

Linked Lists

• Foundations of singly, doubly, and circular linked lists, including dummy‑node techniques.
• Fast & slow pointer patterns (Floyd’s cycle detection, middle‑node retrieval).
• In‑place reversal, merging K sorted lists, palindrome checking, and list reordering.
• Advanced manipulations such as partitioning around a pivot and handling edge cases (null head, single‑node lists).

Stacks

• Core LIFO mechanics and differences between array‑based and node‑based implementations.
• Practical applications: balanced parentheses, infix/postfix/prefix expression evaluation, function‑call stack simulation.
• Monotonic stack patterns for Next Greater Element, Daily Temperatures, and Largest Rectangle in Histogram.
• Design of Min/Max stacks and custom stack extensions for real‑world use cases.

Queues & Deques

• FIFO fundamentals and double‑ended queue operations, including circular queue implementation.
• BFS building blocks, task scheduling, and buffering strategies using Java’s ArrayDeque.
• Monotonic queue techniques for Sliding Window Maximum problems.
• Integration of priority queues and heap structures for bounded‑queue scenarios.

Java Collections Framework (JCF)

• Choosing the right collection (LinkedList, ArrayDeque, PriorityQueue) based on memory and performance needs.
• Comparing built‑in collections with hand‑crafted data structures for interview precision.
• Best practices for iterator usage, fail‑fast behavior, and concurrent modification handling.
• Real‑world case studies: implementing a queue‑based cache and a stack‑driven undo system.

Complexity & Optimization

• Systematic conversion of brute‑force solutions to optimal linear‑time algorithms.
• Detailed Big‑O analysis for each data‑structure operation, emphasizing constant‑space tricks.
• Profiling Java code with simple benchmarking tools to validate performance claims.
• Communicating trade‑offs: when to favor readability over micro‑optimizations in production code.

Who Should Take This Course

• Computer‑Science students and graduates bridging theory with interview‑grade Java DSA.
• Software engineers targeting FAANG/MAANG interview rounds that focus on linear data structures.
• Java developers seeking deeper mastery of reference handling, memory optimization, and JCF usage.
• Self‑taught programmers or bootcamp alumni who need high‑yield LeetCode patterns for technical screens.
• Backend and competitive‑programming engineers aiming to accelerate problem‑solving speed on stacks, queues, and linked lists.

Prerequisites

• Basic proficiency in Java syntax and object‑oriented programming concepts.
• Familiarity with elementary programming constructs (loops, conditionals, arrays).
• Recommended: Prior exposure to simple algorithmic problems (e.g., sorting, searching) to maximize course pacing.

Why Enroll in This Course

The curriculum delivers a focused, interview‑ready skill set without unnecessary fluff, making it ideal for busy engineers. A free coupon grants 100 % off for a limited time, so you can start learning immediately without financial risk. Compared with generic data‑structure tutorials, this course zeroes in on the exact patterns and edge‑case handling that top tech recruiters evaluate, giving you a clear edge in coding interviews.

Course Highlights

• Lifetime access to all video lectures, code files, and practice exercises.
• Mobile‑friendly design lets you code and review concepts on any device.
• Self‑paced format accommodates both full‑time professionals and students.
• Certificate of completion validates your mastery of Java DSA for employers.
• AI‑assisted hints provide instant feedback on common pitfalls during coding practice.
• 30‑day money‑back guarantee ensures a risk‑free learning experience.

Frequently Asked Questions

Q: Is this course really free?
A: Yes. By applying the available free coupon, you receive 100 % off the regular Udemy price, giving you full access at no