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

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

/* 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 pattern = Pattern.compile("^(?:0|63)?\\d{10}\\b");
		String input = "09187654321";
		Matcher m = pattern.matcher(input);
		if (m.find()) {
			System.out.println(m.group());	
		}
	}
}