Find First and Last Position of element in sorted array

Updated Apr 28, 2026

Short answer

Two modified binary searches to find boundaries.

Deep explanation

Intermediate searching challenges involve non-standard data structures or specific constraints. Two modified binary searches to find boundaries.

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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