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

/**
 * A Java application to demonstrate the Java package 
 * java.util.regex. We take one command-line argument, 
 * which is treated as a regexp and compiled into a
 * Pattern. We then use that Pattern to filter the
 * standard input, echoing to standard output only
 * those lines that match the Pattern.
 */
class RegexFilter {
  public static void main(String[] args) 
        throws IOException {

    Pattern p = Pattern.compile(args[0]); // the regexp
    BufferedReader in =  // standard input
      new BufferedReader(new InputStreamReader(System.in));

    // read and echo lines until EOF

    String s = in.readLine();
    while (s!=null) {
      Matcher m = p.matcher(s);
 
      if (m.matches()) System.out.println(s);
      s = in.readLine();
    }
  }
}