#include<bits/stdc++.h>
using namespace std;


class No701{
private :
  string tmp;
  vector<string> a;
  string generateString(){
    string t = "";
    t += tmp[tmp.size()-1];
    for(int i = 0;i < rand()%20;i++){
      t += char(rand()%25+97);
    }
    char last = rand()%25+97;
    t += char(last == 110 ? 97 : last);
    tmp = t;
    a.push_back(tmp);
    return t;
  }
public :
  No701(string s){
    tmp=s;
  }
  vector<string> generateList(int n){
    for(int i=0;i<n;i++){
      generateString();
    }
    do{
    unique(a.begin(),a.end());
    if(a.size() < n)generateString();
    a[a.size()-1] += char(110);
    }while(a.size() != n);
    return a;
  }
};

int main(){
  ios::sync_with_stdio(false);
  int N;
  cin >> N;
  No701 no701("hello");
  vector<string> a = no701.generateList(N);
  for(string e : a){
    cout << e << endl;
  }

  return 0;
}