algorithms

Algorithm implementations
git clone git://git.laack.co/algorithms.git
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longest-palindromic-substring.py (1004B)

      1 def is_palindrome(candidate):
      2     left = 0
      3     right = len(candidate) - 1
      4     while left < right:
      5         if candidate[left] != candidate[right]:
      6             return False
      7         left += 1
      8         right -= 1
      9     return True
     10 
     11 class Solution:
     12     def longestPalindrome(self, s: str) -> str:
     13         
     14         longest = ""
     15         
     16         for i in range(len(s)):
     17             left = i
     18             right = i
     19             while right < len(s) and left >= 0 and is_palindrome(s[left:right + 1]):
     20                 if (right - left) + 1 > len(longest):
     21                     longest = s[left:right + 1]
     22                 left -= 1
     23                 right += 1
     24 
     25         
     26         for i in range(len(s)):
     27             left = i
     28             right = i + 1
     29             while right < len(s) and left >= 0 and is_palindrome(s[left:right + 1]):
     30                 if (right - left) + 1 > len(longest):
     31                     longest = s[left:right + 1]
     32                 left -= 1
     33                 right += 1
     34         
     35         return longest