import java.util.regex.*;

public class Groupe {
    public static void main(String[] args){
	Pattern p = Pattern.compile("(aa(?:b*?))|(aa)");
        Matcher m = p.matcher("baaaaaaaaaabaacbba");
        while (m.find()){
	    System.out.print("indice "+m.start()+" "+m.group()+" ");
            for (int i=1; i<= m.groupCount();i++) 
		System.out.print("groupe "+ i+": "+m.group(i)+" ");
            System.out.println();
        }
    }
}