5. Longest Palindromic Substring

Given a string s, return the longest palindromicsubstring in s.

Example 1:

Input: s = "babad"
Output: "bab"
Explanation: "aba" is also a valid answer.

Example 2:

Input: s = "cbbd"
Output: "bb"

Constraints:

• 1 <= s.length <= 1000
• s consist of only digits and English letters.

class Solution:
    def longestPalindrome(self, s: str) -> str:
        n = len(s)

        def getLen(left, right):
            while left >=0 and right < n and s[left] == s[right]:
                left -=1
                right +=1
            
            return right - left - 1
        
        start = 0
        length = 0
        for i in range(n):
            print("------------------------------")
            print(i)
            cur = max(getLen(i, i), getLen(i, i+1))
            print(cur)
            if cur <= length:
                continue
            length = cur
            start = i - (cur-1) // 2
        
        print("end------------------------------")
        print(s[start:start+length])
        return s[start:start+length]