# 1332. Remove Palindromic Subsequences

#### Easy

***

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: 1
Explanation: s is already a palindrome, so its entirety can be removed in a single step.
```

**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'`.

```python
class Solution:
    def removePalindromeSub(self, s: str) -> int:
        # minimum number of steps to make the given string empty -> it means it will always get empty
        # If already plaindrome remove in 1 step if not then remove 'a' in 1 step and then remove b in 2nd step
        # Hence max 2 steps
        return 1 if s == s[::-1] else 2
```