import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int max = 1;
        for (int i = 0; i < n - 1; i++) {
            max = max * 2;
        }
        for (int i = 0; i < max; i++) {
            String ansString = String.format("%" + n + "s", Integer.toBinaryString(i)).replace(" ", "0");
            System.out.println(ansString.replace("0", "a").replace("1", "b"));
        }
    }
}