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🎮 Hashing Patterns (Practice)

Companion to the Hashing Patterns guide. Prefix-sum hashing: count subarrays summing to k in O(n). Edit and run the code right here — it executes in your browser.

🐍 Your turn​

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🧠 Challenge yourself​

  1. Return the actual subarray index ranges, not just the count.
  2. Longest subarray with sum k.
  3. Why does seen[0]=1 handle prefixes that themselves equal k?

Continue the learning path → Binary Search