LeetCode 516 Longest Palindromic Subsequence - Problem Statement

Solve Longest Palindromic Subsequence from LeetCode. Given a string, find the longest subsequence that reads the same forwards and backwards.

Hint: This reduces to LCS. Compare the string with its reverse. The LCS of a string and its reverse is the longest palindromic subsequence. For 'bbbab', the answer is $4$: the subsequence 'bbbb' uses indices $0$, $1$, $2$, $4$ and reads the same forwards and backwards.