Longest palindromic subsequence

Question

Longest palindromic subsequence Given a string s, write a function to find and return the length of the longest palindromic subsequence present in the string. Example 1 > - **Input:** s = aacbbdaa > - **Output:** 6 > - **Explanation:** aabbaa is the longest palindromic subsequence in the string. Example 2 > - **Input:** s = xyxzlxnx > - **Output:** 5 > - **Explanation:** There are multiple longest palindromic subsequences in the string, one of which is xxzxx. Example 3 > - **Input:** s = abc > - **Output:** 1 > - **Explanation:** There are multiple longest palindromic subsequences in the string, they are 'a', 'b' or 'c'.

Accepted Answer

Optimal Solution: Time Complexity O(N^2), Space Complexity O(1). Codeintuition provides an interactive coding environment for this problem.