Update 0005-longest-palindromic-substring.py

Author: neetcode-gh

python/0005-longest-palindromic-substring.py

@@ -1,13 +1,25 @@
 class Solution:
     def longestPalindrome(self, s: str) -> str:
         res = ""
+        resLen = 0
 
         for i in range(len(s)):
-            for l, r in ((i,i), (i,i+1)): # odd and even lengths
-                while l >= 0 and r < len(s) and s[l] == s[r]:
-                    if (r - l + 1) > len(res):
-                        res = s[l:r + 1]
-                    l -= 1
-                    r += 1
+            # odd length
+            l, r = i, i
+            while l >= 0 and r < len(s) and s[l] == s[r]:
+                if (r - l + 1) > resLen:
+                    res = s[l : r + 1]
+                    resLen = r - l + 1
+                l -= 1
+                r += 1
 
-        return res
+            # even length
+            l, r = i, i + 1
+            while l >= 0 and r < len(s) and s[l] == s[r]:
+                if (r - l + 1) > resLen:
+                    res = s[l : r + 1]
+                    resLen = r - l + 1
+                l -= 1
+                r += 1
+
+        return res