import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		int n = scan.nextInt();
		scan.close();
		String[]w = new String[n];
		char[]c = new char[26];
		for(int i = 0; i < 26; i++) {
			c[i] =  (char) ('a' + i);
		}
		int idx = 0;
		loop: for(int i = 0; i < 26; i++) {
			for(int j = 0; j < 26; j++) {
				for(int k = 0; k < 26; k++) {
					for(int l = 0; k < 26; k++) {
						char []t = {'a', c[i], c[j], c[k], c[l], 'a'};
						if(idx == n - 1) {
							t[5] = 'n';
						}
						w[idx] = String.valueOf(t);
						idx ++;
						if(idx == n) {
							break loop;
						}
					}
				}
			}
		}
		for(String s: w) {
			System.out.println(s);
		}
	}
}