0647-Palindromic-Substrings.py

class Solution:
    def countSubstrings(self, s: str) -> int:
        ans = 0
        for i in range(len(s)):
            ans += self.helper(s, i, i)
            ans += self.helper(s, i, i + 1)
        return ans
    
    def helper(self, s, l, r):    
        ans = 0
        while l >= 0 and r < len(s) and s[l] == s[r]:
            l -= 1
            r += 1
            ans += 1
        return ans