Remove Palindromic Subsequences
You are given a string s consisting only of letters 'a' and 'b'. In a single step you can remove one palindromic subsequence from s.
Return the minimum number of steps to make the given string empty.
A string is a subsequence of a given string if it is generated by deleting some characters of a given string without changing its order. Note that a subsequence does not necessarily need to be contiguous.
A string is called palindrome if is one that reads the same backward as well as forward.
Example 1
Input
s = "ababa"Output
1s is already a palindrome, so its entirety can be removed in a single step.
Example 2
Input
s = "abb"Output
2Remove palindromic subsequence "a" then "bb".
Constraints
- 1 <= s.length <= 1000
- s[i] is either 'a' or 'b'.