MirrorWords

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class MirrorWords {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String str = sc.nextLine();
        sc.close();
        int pairCount = 0;
        List<String> mirrors = new ArrayList<>();

        Pattern regex = Pattern.compile("([@]|[#])([A-Za-z]{3,})(\\1{2})([A-Za-z]{3,})(\\1)");
        Matcher matcher = regex.matcher(str);

        while (matcher.find()){

            pairCount++;
            String raw = matcher.group();

            String[] toCheck = raw.substring(1, raw.length() - 1).split(raw.charAt(0) + "+");
            if (toCheck[0].equals(new StringBuilder(toCheck[1]).reverse().toString())){
                mirrors.add(String.format("%s <=> %s", toCheck[0], toCheck[1]));
            }
        }
        if (pairCount > 0) {
            System.out.println(pairCount + " word pairs found!");
        }
        else {
            System.out.println("No word pairs found!");
        }
        if (!mirrors.isEmpty()) {
            System.out.println("The mirror words are:");
            System.out.println(String.join(", ", mirrors));
        }
        else {
            System.out.println("No mirror words!");
        }

    }
}