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

class Program {
  
  public static string[] abc = {"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n"};
  public static int num = 0;
  
  static void Main(string[] args) {
    int a = int.Parse(Console.ReadLine()); //標準入力
    string tmp = "";
    for(int i=0; i<a; i++) tmp += "1";
    num = int.Parse(tmp);
    Sub(0);
  }
  
  /// base: 0-
  public static void Sub(int base){
    int b = base;
    for(int i=0; i<a; i++){
      if(num % (10 ^ b) == (a - 1)){
        b++;
        Sub(b);
      }else{
      	num += 10 ^ b;
        numshow();
        return;
      }
    }
  }
  
  public static void numshow(){
    int tmp = num;
    string output = "";
    while(tmp){
      int dig = tmp % 10;
      output += abc[dig];
      tmp = tmp / 10;
    }
    string output_r = string.Join("", output.Reverse());
    Console.WriteLine(output_r);
  }
}
