<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:
        n = len(s)
        palindroms = set(list(s))
        result = s[0]
        for j in range(1, n):
            for i in range(n-1):
                if i+j < n:
                    if j==1 and s[i]==s[i+j]:
                        palindroms.add(s[i:i+j+1])
                        if len(result) < j+1:
                            result = s[i:i+j+1]
                    else:
                        if s[i] == s[i+j] and (s[i+1:i+j] in palindroms):
                            palindroms.add(s[i:i+j+1])
                            if len(result) < j+1:
                                result = s[i:i+j+1]
        print(palindroms)
        return result




        
18600