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Learn it properly. Then prove it.

Short, structured lessons on DSA, core CS, Java and interview skills, with real code, honest complexity and the mistakes that cost marks. Every topic ends with a quiz, because recall is the only test that counts.

  • 4tracks
  • 19lessons
  • 2 h 29 mof reading
  • 51practice problems
Arrays· Lesson 2 of 5
Array Traversal and Operations with Time Complexity
Java
int[] nums = {42, 17, 99, 8, 63};

// Index loop - you control i, needed for two-pointer work
for (int i = 0; i < nums.length; i++) {
    System.out.println(i + " -> " + nums[i]);
}
8 min readRead this lesson
Tracks

Pick a path, follow it end to end

Each track is an ordered syllabus. Every lesson links to the next, so you never have to go back to a menu.

How it works

Built to make it stick

Mechanisms, not definitions. Every claim comes with the reason behind it, because that is what an interviewer asks next.

  1. Read one idea at a time

    Short lessons you can finish in one sitting, in the order the ideas actually build on each other.

  2. Practise the pattern

    Every lesson ends with problems tagged by pattern, so you learn the idea and not just the example.

  3. Prove it under pressure

    A timed quiz on every topic, and a mock interview when you are ready. Recall is the only test that counts.

Ready when you are

Learned it? Now battle on it.

Take a quiz solo, share a room code and compete live, or put a whole track to the test in a mock interview.