import java.util.Scanner;


public class Main {
	public static void main(String[] a) {
		int N=new Scanner(System.in).nextInt();
		System.out.println(N==3?"7":String.format("%"+(N%2>0?N-3:N)/2+"s"," ").replace(' ','1')+(N%2>0?"7":""));
	}
}