# Leetcode Longest Palindromic Substring problem solution in Python In the Leetcode Longest Palindromic Substring problem solution in Python programming Given a string s, return the longest palindromic substring in s.

## Leetcode Longest Palindromic Substring problem solution in Python programming

``````class Solution(object):
def longestPalindrome(self, s):
n, max_len, ans = len(s), 0, ''
def expand_around_center(l, r):
if r < n and s[l] != s[r]:
return '' # Index out of range or elements unequal(for even sized palindromes) thus return empty string
while l >= 0 and r < n and s[l] == s[r]: # Till the s[l], s[r] elements are in range and same, the palindrome continues to grow
l, r = l - 1, r + 1
return s[l + 1:r] # Return the palindrome formed
for i in range(n):
a, b = expand_around_center(i, i), expand_around_center(i, i + 1) # (i,i) for odd and (i,i+1) for even sized palindromes
main = a if len(a) > len(b) else b # Check which one of a, b is larger
if len(main) > max_len: # Check if palindrome with i as center is larger than previous entries then update if necessary
max_len, ans = len(main), main
return ans`````` #### By Neha Singhal

Hi, my name is Neha singhal a software engineer and coder by profession. I like to solve coding problems that give me the power to write posts for this site.