Skip to main content

NOTICE: On Friday Nov 6, Workspaces will be temporarily unavailable for maintenance.

🚀 In our NEW AI Bootcamp you'll build a working app in 28 days, no experience required. Free to all subscription levels.

✨ Earn college credits in Cybersecurity, JS, HTML, CSS and Python

Join the Treehouse affiliate program and earn 25% recurring commission! 🤑

  • Treehouse Logo
    • For Individuals
    • For Businesses
    • For Schools
    • For Libraries
    • For Military
    • All Courses
    • Tracks
    • AI Bootcamp
    • College Credit
    • Techdegree Bootcamps
    • Front End Development
    • Full Stack JavaScript
    • Code Adventures
    • Discord
    • Forum
    • Success Stories
    • Treehouse Links
    • 100 Days of Code
    • Explore
    • Career Toolbox
    • Free Treehouse Near Me
    • Affiliates
    • Blog
    • Support
    • About
    • Learn
    • Beginner's Guide to Coding
    • Data Analysis with SQL & Python
    • Front-End Web Development
    • Python Programming Basics
    • Techdegree Bootcamp Overview
    • UX Design Fundamentals
    • AI Tools for Beginners
  • For Individuals For Businesses For Schools For Libraries For Military
  • All Courses Tracks AI Bootcamp College Credit
  • Techdegree Bootcamps Front End Web Development Full Stack JavaScript
  • Code Adventures Discord Forum Success Stories Treehouse Links 100 Days of Code
  • Explore Career Toolbox Free Treehouse Near Me Affiliates Blog Support About
    Learn Beginner's Guide to Coding Data Analysis with SQL & Python Front-End Web Development Python Programming Basics Techdegree Bootcamp Overview UX Design Fundamentals AI Tools for Beginners
  • Sign In
  • Free Trial
Instagram Twitter Facebook YouTube LinkedIn
Loading banner... Start your free trial at Treehouse
    • Newest
      • Newest
      • Active
      • Unanswered
      • Featured
    • All Topics
      • All Topics
      • • General Discussion
      • • AI
      • • APIs
      • • Coding for Kids
      • • College Credit
      • • Computer Science
      • • CSS
      • • Data Analysis
      • • Databases
      • • Design
      • • Development Tools
      • • Digital Literacy
      • • Game Development
      • • Go Language
      • • HTML
      • • Java
      • • JavaScript
      • • Learning Resources
      • • Machine Learning
      • • No-Code
      • • PHP
      • • Professional Growth
      • • Python
      • • Quality Assurance
      • • React
      • • Ruby
      • • Security
      • • Swift
      • • Vibe Coding
  • Erick Luna
    Erick Luna
    21,985 Points

    Course about to be removed?

    Posted May 15, 2025 10:01pm by Erick Luna
    Erick Luna
    21,985 Points
    • Java
    • Introduction to Functional Programming
    • Reduction and Aggregation
    • Reduction Operations

    0 Answers

  • hamsternation
    hamsternation
    26,617 Points

    Ranges vs Limits?

    Posted January 1, 2022 2:04am by hamsternation
    hamsternation
    26,617 Points
    • Java
    • Introduction to Functional Programming
    • Reduction and Aggregation
    • Ranges

    1 Answer

  • hamsternation
    hamsternation
    26,617 Points

    Is using int PageSize and int PageNumber kosher declarative code?

    Posted January 1, 2022 1:53am by hamsternation
    hamsternation
    26,617 Points
    • Java
    • Introduction to Functional Programming
    • Reduction and Aggregation
    • Infinite Streams

    0 Answers

  • Nancy Melucci
    PLUS
    Nancy Melucci
    Courses Plus Student 36,809 Points

    The files for the later stages aren't working in IntelliJ

    Posted June 9, 2019 4:08am by Nancy Melucci
    Nancy Melucci
    Courses Plus Student 36,809 Points
    • Java
    • Introduction to Functional Programming
    • Reduction and Aggregation
    • Ranges

    3 Answers

  • Tacir Ozdemir
    Tacir Ozdemir
    19,655 Points

    Answer ?

    Posted March 20, 2019 11:24am by Tacir Ozdemir
    Tacir Ozdemir
    19,655 Points
    • Java
    • Introduction to Functional Programming
    • Reduction and Aggregation
    • Optional Quiz...Homonym Fail, it is Required

    1 Answer

  • Steve Lewin
    Steve Lewin
    6,784 Points

    stateCodesIgnoreBlanks FAILED and not sure why

    Posted December 23, 2018 11:04pm by Steve Lewin
    Steve Lewin
    6,784 Points
    • Java
    • Introduction to Functional Programming
    • Reduction and Aggregation
    • Ranges

    1 Answer

  • David Lin
    David Lin
    35,864 Points

    Minor bug in video code: companies.get(i-1)

    Posted May 4, 2017 5:10pm by David Lin
    David Lin
    35,864 Points
    • Java
    • Introduction to Functional Programming
    • Reduction and Aggregation
    • Infinite Streams

    1 Answer

Posting to the forum is only allowed for members with active accounts.
Please sign in or sign up to post.

Techdegree

  • Front End Web Development
  • Full Stack JavaScript
SEE ALL

Tracks

  • Learn to Code for Beginners
  • Beginning Python
  • Beginning SQL
  • Beginning Java
SEE ALL

Courses

  • JavaScript Basics
  • Intro to HTML & CSS
  • Python Basics
  • CSS Layout
SEE ALL

About Us

  • About
  • Blog
  • Community
  • Stories
  • Contact
  • Gift Card

Explore

  • Plans
  • Affiliates
  • Perks
  • Shop
  • Free Treehouse Near Me
  • Treehouse for Libraries
  • Treehouse for Businesses

Treehouse is an online technology education platform founded in 2011. Treehouse offers more than 700 self-paced, video-based courses in web development, programming, data analysis, design, and AI, plus two project-based bootcamp programs in Front End Web Development and Full Stack JavaScript. Individual Treehouse plans start at $25 per month and include a 7-day free trial. Treehouse serves individual learners, businesses, schools, and public libraries. Cardholders at participating U.S. public libraries can use Treehouse for free. Select Treehouse courses, offered with University Pathways International, are recommended for college credit by ACE and NCCRS. Treehouse learners earn digital certificates for completed Tracks.

Terms & Conditions · Privacy · © 2026 Treehouse Island, Inc.
  • Twitter
  • YouTube
  • Facebook
  • LinkedIn
  • Instagram
  • Discord