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Java

Learn and practice Java with this online tutorial and challenges!

Learn Programming with Java

Web Development

Learn how to create web applications.

Intro to Creating Websites

Programming Practice

Practice programming by solving challenges.

Logic and Loops Practice

Algorithms

Learn Algorithms and Data Structures by Solving Challenges. Pick a topic and Learn by Doing!

Basic Data Structures

Contests

Explore programming challenges from past contests.

Prepare for the Ruby Coding Contest

Learn by Example

Learn or reference new languages with example code and challenges.

Learn Python by Example

Mathematics

Learn Combinations and Probability.

Combinations & Permutations

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Other