#include <bits/stdc++.h>
using namespace std;
#pragma GCC target("avx2")
#pragma GCC optimization("unroll-loops")
#pragma GCC optimize("O2")
constexpr int dx[] = {-1, 0, 1, 0, 1, 1, -1, -1};
constexpr int dy[] = {0, -1, 0, 1, 1, -1, 1, -1};
constexpr long long INF = 1999999999999999997;
constexpr int inf = INT_MAX;
constexpr int MAXSIZE = int(1e6) + 5;
constexpr auto PI = 3.14159265358979323846L;
constexpr auto oo = numeric_limits<int>::max() / 2 - 2;
constexpr auto eps = 1e-6;
constexpr auto mod = 1000000007;
constexpr auto MOD = 1000000007;
constexpr auto MOD9 = 1000000009;
constexpr auto maxn = 100006;
void fastio() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
}
int main() {
  fastio();
  int n;
  cin >> n;
  string s1, s2;
  for (int i = 0; i < n; i++) {
    s1.push_back('a');
    if (i <= n - 2) s2.push_back('a');
  }
  s2.push_back('a' + 1);
  vector<string> ans;
  ans.push_back(s1);
  int cnt = 1;
  do {
    ans.push_back(s2);
    cnt++;
  } while (next_permutation(s2.begin(), s2.end()) && cnt < n);
  sort(ans.begin(), ans.end());
  for (int i = 0; i < n; i++) {
    cout << ans[i] << "\n";
  }
}
