import java.util.*;
    import java.lang.*;
    import java.util.regex.*;
    class Main {
    	public static void main(String[] args) {
    		String input1 = "Request ECUReset for [*11 01]";
    		String output1 = getBracketValue(input1);
    		System.out.println(input1 + " --> " + output1);
    		
    		String input2 = "Request ECUReset for [*11]";
    		String output2 = getBracketValue(input2);
    		System.out.println(input2 + " --> " + output2);
    		
    		String input3 = "Request ECUReset for [*11 01 10]";
    		String output3 = getBracketValue(input3);
    		System.out.println(input3 + " --> " + output3);
    	}
    	private static String getBracketValue(String input) {
    		Matcher m = Pattern.compile("(?<=\\[\\*)[^\\]]*(?=\\])").matcher(input);
    	    if (m.find()) {
    	    	return m.group();
    	    }
    		return null;
    	}
    }