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You are given two strings, word1 and word2. You want to construct a string in the following manner:

  • Choose some non-empty subsequence subsequence1 from word1.
  • Choose some non-empty subsequence subsequence2 from word2.
  • Concatenate the subsequences: subsequence1 + subsequence2, to make the string.

Return the length of the longest palindrome that can be constructed in the described manner. If no palindromes can be constructed, return 0.

A subsequence of a string s is a string that can be made by deleting some (possibly none) characters from s without changing the order of the remaining characters.

A palindrome is a string that reads the same forward as well as backward.

 

Example 1:

Input: word1 = "cacb", word2 = "cbba"
Output: 5
Explanation: Choose "ab" from word1 and "cba" from word2 to make "abcba", which is a palindrome.

Example 2:

Input: word1 = "ab", word2 = "ab"
Output: 3
Explanation: Choose "ab" from word1 and "a" from word2 to make "aba", which is a palindrome.

Example 3:

Input: word1 = "aa", word2 = "bb"
Output: 0
Explanation: You cannot construct a palindrome from the described method, so return 0.

 

Constraints:

  • 1 <= word1.length, word2.length <= 1000
  • word1 and word2 consist of lowercase English letters.

class Solution { public int longestPalindrome(String word1, String word2) { } }