import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int ans = 0;
        if(n%2==0) ans+=1;
        else ans+=7;
        int m = (int)Math.ceil(n/2);
        for(int i=1; i<m; i++) {
            ans+=Math.pow(10, i);
        }
        System.out.println(ans);
    }
}