using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;

class TEST{
	static void Main(){
		Sol mySol =new Sol();
		mySol.Solve();
	}
}

class Sol{
	public void Solve(){
		
		var sb = new StringBuilder();
		char[] ca = "a??????????a".ToCharArray();
		var abcd  = "abcd";
		for(int i=0;i<N;i++){
			for(int k=0;k<10;k++){
				ca[1+k] = abcd[ (i >> (k * 2)) & 3];
			}
			if(i == N - 1) ca[ca.Length - 1] = 'n';
			sb.AppendLine(new String(ca));
		}
		
		Console.Write(sb.ToString());
		
	}
	int N;
	public Sol(){
		N = ri();
	}

	static String rs(){return Console.ReadLine();}
	static int ri(){return int.Parse(Console.ReadLine());}
	static long rl(){return long.Parse(Console.ReadLine());}
	static double rd(){return double.Parse(Console.ReadLine());}
	static String[] rsa(char sep=' '){return Console.ReadLine().Split(sep);}
	static int[] ria(char sep=' '){return Array.ConvertAll(Console.ReadLine().Split(sep),e=>int.Parse(e));}
	static long[] rla(char sep=' '){return Array.ConvertAll(Console.ReadLine().Split(sep),e=>long.Parse(e));}
	static double[] rda(char sep=' '){return Array.ConvertAll(Console.ReadLine().Split(sep),e=>double.Parse(e));}
}