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Longest Palindromic Substring is a medium coding interview question covering strings, dynamic programming, two pointers — the kind asked at FAANG (Facebook/Meta, Apple, Amazon, Netflix, Google) and AI-first companies like Anthropic, OpenAI, and Nvidia.
Given a string s, return the longest substring of s that is a palindrome. If there are ties, any longest palindromic substring is accepted.
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A full interview loop is more than one round. These are the others, each with what is on the site for it.