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> (k * 2)) & 3]; } 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));} }