<p>Given a string <code>s</code>, return <em>the longest</em> <span data-keyword="palindromic-string"><em>palindromic</em></span> <span data-keyword="substring-nonempty"><em>substring</em></span> in <code>s</code>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> s = &quot;babad&quot;
<strong>Output:</strong> &quot;bab&quot;
<strong>Explanation:</strong> &quot;aba&quot; is also a valid answer.
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> s = &quot;cbbd&quot;
<strong>Output:</strong> &quot;bb&quot;
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= s.length &lt;= 1000</code></li>
	<li><code>s</code> consist of only digits and English letters.</li>
</ul>

class Solution:
    def longestPalindrome(self, s: str) -> str:
        def is_palindrome(sub: str) -> bool:
            return sub == sub[::-1]  # Check if the substring is equal to its reverse

        n = len(s)
        longest_palindrome = ""

        # Generate all possible substrings
        for i in range(n):
            for j in range(i + 1, n + 1):
                substring = s[i:j]
                if is_palindrome(substring):
                    if len(substring) > len(longest_palindrome):
                        longest_palindrome = substring
        
        return longest_palindrome


        
16700