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We used find the longest palindrome in a string as an interview question at Amazon back in 2004

Did you require a certain time complexity? I came across this on Leetcode. I found it really trivial to implement the “test all substrings” algorithm, but fiendishly difficult to implement the “expand around centers” algorithm.

That's why trick puzzle questions are bad interview questions. Some people have read the centers algorithm

It’s not a trick question. It’s just writing a loop any CS graduate or equivalent autodidact should have absolutely no problem with.

We didn’t require any specific time or space complexity. If the candidate whipped out a suboptimal solution quickly and correctly and time permitted we might ask them about that though and how it might be improved. The purpose of the question is not to see if the candidate has memorized the answer or sees a trick, it’s so they can demonstrate basic proficiency and systematic reasoning.

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