_1337.java

package com.fishercoder.solutions;

/**
 * 1337. Remove Palindromic Subsequences
 *
 * 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
 * Explanation: String is already palindrome
 *
 * 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".
 *
 * Example 4:
 * Input: s = ""
 * Output: 0
 *
 * Constraints:
 * 0 <= s.length <= 1000
 * s only consists of letters 'a' and 'b'
 * */
public class _1337 {
    public static class Solution1 {
        public int removePalindromeSub(String s) {
            if (s.isEmpty()) {
                return 0;
            } else {
                String reverse = new StringBuilder(s).reverse().toString();
                if (s.equals(reverse)) {
                    return 1;
                } else {
                    return 2;
                }
            }
        }
    }
}