import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String regex = "-a-([^\\?]+)\\?";
        String string = "location/city/home-a-berlin?/someNewAdress\n";
        
        Pattern pattern = Pattern.compile(regex);
        Matcher matcher = pattern.matcher(string);
        
        if (matcher.find()) {
            System.out.println(matcher.group(1));
        }
	}
}