About this challenge
Binary Search is a medium algorithms coding challenge. It tests algorithmic thinking and complexity analysis — the kind of problem-solving that shows up constantly in technical interviews. Write your solution in the editor above, run it against the test cases, and get instant feedback — free, in your browser, no sign-up.
Show a hint & approach (spoiler)
Hint: Maintain lo and hi pointers. At each step compute mid = lo + ((hi - lo) >> 1) to avoid overflow.
Keep practicing
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