Search in an Infinite Array

Updated Apr 28, 2026

Short answer

Exponentially increase the range until target is found, then binary search.

Deep explanation

Intermediate searching challenges involve non-standard data structures or specific constraints. Exponentially increase the range until target is found, then binary search.

Real-world example

Finding a word in a partially organized document.

Common mistakes

  • Using O(n) for a 2D matrix search when O(log(m*n)) is possible.

Follow-up questions

  • Why is mid = (low + high) // 2 potentially dangerous?

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