<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 {
public:
    
    bool solve( int i ,string &p , int n){
        if(i>=n/2) return true;
    
        if(p[i] != p[n-i-1]) return false;
        return solve(i+1,p,n);
    }

    string solve(string &s){
         int n = s.size();
         int maxlen = INT_MIN;
         string str = "";
        unordered_map<string ,int>umpp;
    
        for(int i =0 ;i<n;i++){
           string p="";
            for(int j =i;j<n;j++){
                p+=s[j];
                if( solve(0 ,p , p.size())){
                   int x = p.size();
                    maxlen = max(maxlen ,x);
                    umpp[p] = x;
                }
            }
        }
    
        for(auto it : umpp){
            if(it.second == maxlen){
             str = it.first;
            break;
            }
        }
        return str;
    }

    string longestPalindrome(string s) {
        return solve(s);
        
    }
};
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