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:

Input:

1 |
"bbbab" |

Output:

1 |
4 |

One possible longest palindromic subsequence is “bbbb”.

Example 2:

Input:

Input:

1 |
"cbbd" |

Output:

1 |
2 |

One possible longest palindromic subsequence is “bb”.

## Java Solution

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package com.javagists.learn.interview.questions; public class LongestPalindromeSubsequence { public int longestPalindromeSubseq(String input) { int[][] dp = new int[input.length()][input.length()]; for (int i = input.length() - 1; i >= 0; i--) { dp[i][i] = 1; for (int j = i + 1; j < input.length(); j++) { if (input.charAt(i) == input.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][input.length() - 1]; } public static void main(String[] args) { LongestPalindromeSubsequence longestPalindromeSubsequence = new LongestPalindromeSubsequence(); System.out.println(longestPalindromeSubsequence.longestPalindromeSubseq("bbbaabbgghj")); } } |

You can find the source code at github

why does your code not compile?

It compiles for me and you can find the file on github also. I have also added link to the github also