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# Remove Palindromic Subsequences

Updated: Mar 24, 2021

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.

A string is called palindrome if is one that reads the same backward as well as forward.

Example 1:

```Input: s = "ababa"
Output: 1

```

Example 2:

```Input: s = "abb"
Output: 2
Explanation: "abb" -> "bb" -> "".
Remove palindromic subsequence "a" then "bb".

```

Example 3:

```Input: s = "baabb"
Output: 2
Explanation: "baabb" -> "b" -> "".
Remove palindromic subsequence "baab" then "b".

```

Constraints:

• 1 <= s.length <= 1000

• s[i] is either 'a' or 'b'.

Solution:

```
class Solution {
public int removePalindromeSub(String s) {
if(s.length()==0) return 0;
StringBuilder sb=new StringBuilder(s);
if(sb.reverse().toString().equals(s)) return 1;
return 2;
}
}```