import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Main {
	
	public static void main (String[] args) {
		
		String input = "foobar foo bar 'foobar' 'foo bar' 'foo''bar'";
		Pattern pattern = Pattern.compile("'(?:[^']|'')+'|[^ ]+");
		Matcher matcher = pattern.matcher(input);
		while (matcher.find()) {
			String match = matcher.group();
			System.out.println(match);
		}
		
	}
	
}