class Solution

 {

 public:

     int longestPalindromeSubseq(string s)

     {

         int n = s.length();

         int dp[][];

         for (int i = ; i < n; i++)

         {

             dp[i][i] = ;

             if (i != n - ) dp[i][i + ] = (s[i] == s[i + ] ?  : );

         }

         for (int i = n - ; i >= ; i--)

         {

             for (int j = i + ; j < n; j++)

             {

                 if (s[i] == s[j]) dp[i][j] = dp[i + ][j - ] + ;

                 else dp[i][j] = max(dp[i + ][j], dp[i][j - ]);

             }

         }

         return dp[][n - ];

     }

 };