import java.io.BufferedReader;
import java.io.InputStreamReader;
class Main1343 {
//https://www.acmicpc.net/problem/1343
private static final String A = "AAAA";
private static final String B = "BB";
public static void main(String[] args) throws Exception {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String input = br.readLine();
while (input.contains("XXXX")) {
input = input.replaceFirst("XXXX", A);
}
while (input.contains("XX")) {
input = input.replaceFirst("XX", B);
}
if (input.contains("X")) {
System.out.println(-1);
return;
}
System.out.println(input);
}
}
휴지통/알고리즘 & 자료구조