Longest Palindrome by Concatenating Two Letter Words

LongestPalindromeFromTwoLetterWords.java

//https://leetcode.com/problems/longest-palindrome-by-concatenating-two-letter-words/
class Solution {
    public int longestPalindrome(String[] words) {
        int n = words.length, count = 0;
        Map<String, Integer> visited = new HashMap<>();
        for(int i=0;i<n;i++){
            String word = words[i];
            String reverseWord = word.charAt(1) + "" + word.charAt(0) ;
            if(visited.containsKey(reverseWord) && visited.get(reverseWord)>0){
                count += 4;
                visited.put(reverseWord, visited.get(reverseWord) - 1);
            }
            else{
                visited.put(word, visited.getOrDefault(word, 0) + 1);
            }
        }
        for(String remainingWord:visited.keySet()){
            if((remainingWord.charAt(0) == remainingWord.charAt(1)) && visited.get(remainingWord)>0){
                count += 2;
                break;
            }
        }
        return count;
    }
}