/* 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
	{
		System.out.println(fetchMatch("test", 0));
		System.out.println(fetchMatch("one&test", 0));
		System.out.println(fetchMatch("&test", 0));
	}
	public static String fetchMatch(String s, int groupId)
	{
 		Pattern pattern = Pattern.compile("^[^&]+");
		Matcher matcher = pattern.matcher(s);
		if (matcher.find()){
			return matcher.group(groupId); 
		} 
		return "ERROR: NOT MATCHED";
	}
}

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