<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:
    string getsubstr(string s,int i,int j)
    {
        string ans="";
        for(int k=i;k<=j;k++){ans+=s[k];}
        return ans;
    }
    string longestPalindrome(string s) {
        int n=s.length();
        vector<vector<int>> dp(n,vector<int>(n,0));
        for(int i=0;i<n;i++)
        {
            for(int j=i;j>=0;j--)
            {
                
                if(i==j){dp[i][j]=1;}
                else if(i-j==1)
                {
                    if(s[i]==s[j]){dp[i][j]=1;}
                    // else{dp[i][j]=0;}
                }
                else if(dp[i-1][j+1]==1&&s[i]==s[j])
                {
                    dp[i][j]=1;
                }
                
            }
            
        }
        
        int ans=0;
        string h="";
        for(int i=0;i<n;i++)
        {
            int mi=INT_MAX,ma=-1;
            for(int j=0;j<=i;j++)
            {
                if(dp[i][j]){mi=min(mi,j);ma=max(ma,j);}
            }
            if((ma-mi)>=ans){ans=ma-mi;h=getsubstr(s,mi,ma);}
        }
        return h;
        
    }
};
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