Software Engineering

12,898 learners

Mastering Algorithms: HashMaps, Two Pointers, and Beyond in Java

Dive into the key algorithms involving HashMaps, HashSets, and two-pointer techniques. This course will enhance your skills in optimizing data structures and problem-solving methods.

Java

See path

5 lessons

15 practices

3 hours

General Programming and Algorithms

Course details

Complexity Analysis and Optimization in Java

Preview

Summing Points Between Two Towns in Integerland

Finding the Smallest Absolute Difference in an Integer List

Optimized Array Replacement

Previous Course Next Course: Maximizing Efficiency in Problem-Solving Techniques in Java

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I'm impressed by the quality and can't stop recommending it. It's also a lot of fun!

Francisco Aguilar Meléndez

Data Scientist

+11

I love that it's personalized. When I'm stuck, I don't have to hope my Google searches come out successful. The AI mentor Cosmo knows exactly what I need.

Faith Yim

Software Engineer

+14

It's an amazing product and exceeded my expectations, helping me prepare for my job interviews. Hands-on learning requires you to actually know what you are doing.

Alex Bush

Full Stack Engineer

I'm really impressed by the AI tutor Cosmo's feedback about my code. It's honestly kind of insane to me that it's so targeted and specific.

Abbey Helterbran

Tech consultant

I tried Leetcode but it was too disorganized. CodeSignal covers all the topics I'm interested in and is way more structured.

Jonathan Miller

Senior Machine Learning Engineer

+12

I'm impressed by the quality and can't stop recommending it. It's also a lot of fun!

Francisco Aguilar Meléndez

Data Scientist

+11

From our community

Hear what our customers have to say about CodeSignal Learn

I'm impressed by the quality and can't stop recommending it. It's also a lot of fun!

Francisco Aguilar Meléndez

Data Scientist

+11

I love that it's personalized. When I'm stuck, I don't have to hope my Google searches come out successful. The AI mentor Cosmo knows exactly what I need.

Faith Yim

Software Engineer

+14

It's an amazing product and exceeded my expectations, helping me prepare for my job interviews. Hands-on learning requires you to actually know what you are doing.

Alex Bush

Full Stack Engineer

I'm really impressed by the AI tutor Cosmo's feedback about my code. It's honestly kind of insane to me that it's so targeted and specific.

Abbey Helterbran

Tech consultant

I tried Leetcode but it was too disorganized. CodeSignal covers all the topics I'm interested in and is way more structured.

Jonathan Miller

Senior Machine Learning Engineer

+12

I'm impressed by the quality and can't stop recommending it. It's also a lot of fun!

Francisco Aguilar Meléndez

Data Scientist

+11

Mastering Algorithms: HashMaps, Two Pointers, and Beyond in Java

Course details

Unit 13 practices39 min

Unit 23 practices39 min

Unit 33 practices39 min

Unit 43 practices39 min

Unit 53 practices39 min

Turn screen time into skills time

Join the 1M+ learners on CodeSignal

From our community

From our community