import java.io.FileNotFoundException;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) throws FileNotFoundException {
		new Main().run();
	}

	String s = "abcdefghijklmnopqrstuvwxyz";

	void run() throws FileNotFoundException {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		PrintWriter pw = new PrintWriter(System.out);
		while (n > 0) {
			pw.print("a");
			for (int i = 0; i < 6; ++i) {
				pw.print(s.charAt((int) (n / Math.pow(10, i) % 10)));
			}
			if (n > 1)
				pw.println("a");
			else
				pw.println("n");
			--n;
		}
		pw.close();
	}

	void tr(Object... objects) {
		System.out.println(Arrays.deepToString(objects));
	}
}