#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const bool dbg_flg = 1;
const int inf = 1e9 + 7;
const int MAXN = 2e5 + 5;
int n;
void rec(string s) {
  if ((int)(s).size() == n) {
    cout << s << '\n';
    return;
  }
  int ct[30];
  memset(ct, 0, sizeof(ct));
  for (char i : s) {
    ct[i - 'a']++;
  }
  int x = -1;
  int y = -1;
  for (int i = 0; i < 26; i++) {
    if (ct[i] & 1) {
      x = i;
      break;
    }
  }
  for (int i = 0; i < 26; i++) {
    if (!ct[i]) {
      y = i;
      break;
    }
  }
  if (x == -1) {
    rec(s + char(y + 'a'));
  } else {
    if (y > x) swap(x, y);
    rec(s + char(y + 'a'));
    rec(s + char(x + 'a'));
  }
}
void solve() {
  cin >> n;
  rec("");
}
int main() {
  ios_base::sync_with_stdio(NULL);
  cin.tie(NULL);
  cout.tie(NULL);
  int tt = 1;
  while (tt--) {
    solve();
  }
  return 0;
}
