Longest Palindrome | Dataford Interview Questions

A Sumo Logic backend service receives a compact log fragment as a string. Return its longest contiguous substring that is a palindrome, meaning it reads identically from left to right and right to left.

If multiple palindromic substrings have the maximum length, return the one with the smallest starting index.

Formal Specification

Implement longest_palindrome(s).

Input: s, a string containing lowercase English letters.
Output: A string containing the longest palindromic substring of s.

A palindrome must be contiguous. For example, "aba" is valid within "caba", but "aa" formed from non-adjacent characters is not a substring.

Constraints

1 <= len(s) <= 2000
s contains only lowercase English letters
The palindrome must be a contiguous substring
If multiple answers have the same maximum length, return the leftmost one

Function Signature

def longest_palindrome(s):

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