[백준] 1343번 폴리오미노 (silver 5

import java.io.*;
import java.util.*;

public class Main{
    public static void main(String[] args) throws IOException{
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

        String q=br.readLine().concat(".");
        String answer="";
        int repeat=0;

        for(int i=0; i<q.length(); i++){
            char temp=q.charAt(i);
            if(temp=='X'){
                repeat++;
                if(repeat==4){
                    answer=answer.concat("AAAA");
                    repeat=0;
                }
            }
            else{
                if(repeat%2!=0){
                    answer="-1";
                    break;
                }
                else if(repeat==2){
                    answer=answer.concat("BB");
                    repeat=0;
                }
                if(i!=q.length()-1){
                    answer=answer.concat(".");
                }
            }
        }
        System.out.println(answer);
    }
}

//오랜만이라 그런지 코드가 좀 꼬이고 더러운 느낌이 난 거 같다.