#include <bits/stdc++.h>
int faster_in() {
  int r = 0, c;
  for (c = getchar(); c <= 32; c = getchar())
    ;
  if (c == '-') return -faster_in();
  for (; c > 32; r = (r << 1) + (r << 3) + c - '0', c = getchar())
    ;
  return r;
}
using namespace std;
const double PI = acos(-1);
const double EPS = 1e-9;
char mapa[12345];
string change(string txt) {
  string res;
  memset(mapa, 0, sizeof mapa);
  char chr = 'a';
  for (int i = 0; i < txt.size(); i++) {
    if (mapa[txt[i]] == 0) mapa[txt[i]] = chr++;
    res += mapa[txt[i]];
  }
  return res;
}
set<string> s;
void go(string txt, int pos) {
  if (pos == 4) {
    s.insert(change(txt));
    return;
  }
  go(txt + "a", pos + 1);
  go(txt + "b", pos + 1);
  go(txt + "c", pos + 1);
}
int main() {
  string txt;
  ios::sync_with_stdio(false);
  cin.tie(0);
  vector<string> v;
  go("", 0);
  auto ite = s.begin();
  for (int i = 0; i < 10; i++) {
    v.push_back(*ite);
    ite++;
  }
  int n;
  cin >> n;
  for (int i = 0; i < n; i++) {
    txt = v[i];
    while (txt.size() < n) txt = "a" + txt;
    while (txt.size() > n) txt = txt.substr(1);
    cout << txt << endl;
  }
}
