/* 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 xvfbPropsFile = "Xvfb Display Properties\n" +
								"Wed Jul 27 18:31:50 CEST 2016\n" +
								"DISPLAY=\\:20\n" +
								"XAUTHORITY=/tmp/Xvfb4443942380574278711.Xauthority";
		Pattern p = Pattern.compile("DISPLAY.*([0-9][0-9])");
		Matcher m=p.matcher(xvfbPropsFile);
		if (m.find()){
    		System.out.println(m.group(1));
		}
	}
}

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