/* package whatever; // don't place package name! */

import java.util.regex.*;
import java.lang.*;
import java.io.*;

/* 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
	{
         Pattern p = Pattern.compile("(x.|x.y?)+");
         String s = new String(new char[343]).replace("\0", "x");
         if (p.matcher(s).matches())
             System.out.println("Match successful!");
    }
}