/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.regex.*;
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String s = "aaaaaa";
		Matcher m = Pattern.compile("(?=(aa))").matcher(s);
		List<Integer> pos = new ArrayList<Integer>();
		while (m.find())
		{
			pos.add(m.start());
		}
		System.out.println(pos);
	}
}

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