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DSA Dojo

See the pattern. Run the code. Pass the interview round.

The interview patterns that show up again and again — arrays, hash maps, two pointers, sliding windows, stacks, and binary search. Every lesson has a tiny walkthrough, an animated visualizer, and Python practice in the sandbox.

Learn with Ada, your AI coding mentor — ask questions or tap I’m stuck in any lesson for a nudge without spoilers.

Beginner14 lessons~9h
First lesson free

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Course content

1 · Mindset

  • ○Big-O Without the PanicFree12 min

2 · Arrays

  • 🔒Arrays: Index, Scan, Done15 min
  • 🔒Prefix Sums: Range Sums in O(1)18 min

3 · Hashing

  • 🔒Hash Maps: Value → Index in a Blink16 min
  • 🔒Two Sum20 min
  • 🔒Contains Duplicate14 min
  • 🔒Valid Anagram16 min

4 · Two Pointers

  • 🔒Two Pointers: Meet in the Middle16 min
  • 🔒Valid Palindrome18 min
  • 🔒Container With Most Water22 min

5 · Sliding Window

  • 🔒Fixed Window: Max Sum of Size K18 min
  • 🔒Longest Substring Without Repeating22 min

6 · Stacks

  • 🔒Valid Parentheses18 min

7 · Binary Search

  • 🔒Binary Search on a Sorted Array18 min