516 Longest Palindromic Subsequence

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Given a string s, find the longest palindromic subsequence's length in s. You may assume that the maximum length of s is 1000.

Example 1:
Input:

"bbbab"

Output:

4

One possible longest palindromic subsequence is "bbbb".

Example 2:
Input:

"cbbd"

Output:

2

One possible longest palindromic subsequence is "bb".

public class Solution {
    public int longestPalindromeSubseq(String s) {
       
        int[][] dp = new int[s.length()][s.length()]; 
        
        //bbbab
        for(int i=s.length()-1;i>=0;i--){
            
            dp[i][i]=1;
            
            for(int j=i+1;j<s.length();j++){
                
                if (s.charAt(i) == s.charAt(j)) {
                    dp[i][j] = dp[i+1][j-1] + 2;
                } else {
                    dp[i][j] = Math.max(dp[i+1][j], dp[i][j-1]);
                }
                
            }
            
        }
        
          return dp[0][s.length()-1];
    }
}