#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (n); ++i)
using ll = long long;
using ull = unsigned long long;

inline string f(int n) {
  string ans = "";
  while (n) {
    ans += n % 26 + 'a';
    n /= 26;
  }
  return ans;
}

int main() {
  cin.tie(nullptr)->sync_with_stdio(false);
  int n;
  cin >> n;
  rep(i, n) {
    cout << 'a' << f(i) << (i + 1 == n ? 'n' : 'a') << '\n';
  }
  return 0;
}