Here's a link
Given a string s, return the longest palindromic substring in s. A string is called a palindrome string if the reverse of that string is the same as the original string.
Input: s = "babad" Output: "bab" Explanation: "aba" is also a valid answer.
Input: s = "cbbd" Output: "bb"
from collections import defaultdict def is_palindrome(s): return s == s[::-1] def solve(s): seen = defaultdict(list) found = '' for i, char in enumerate(s): if seen[char]: for j in seen[char]: ss = s[j : i + 1] if is_palindrome(ss): found = max(ss, found, key=len) break seen[char].append(i) if not found: found = s return found