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System.out.println("Welcome to learncs.online!");
System.out.print("We are ");
for (int i = 0; i < 4; i++) {
System.out.print("so ");
}
System.out.println("excited to start your journey in computer science!");

Learn Computer Science Online

  • 61 focused lessons—from "Hello, world" to graph recursion
  • Learn Java or Kotlin
  • 900 editable and runnable code examples
  • 2,286 interactive explanations from 240 instructors, including 162 hours of live coding walkthroughs
  • 123 programming problems covering all core language features
  • 384,583 debugging challenges that train you to fix small mistakes
  • One goal: Teaching you about computer science and programming!

We'll teach you the basics of computer science and programming. Once you know these things, you can and will change the world.

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