#include <bits/stdc++.h>
const int maxn = 2e5 + 9;
const double pi = acos(-1);
const int mod = 1e9 + 7;
const int INF = 0x3f3f3f3f;
const double ep = 1e-7;
using namespace std;
int main() {
  int n;
  int a[20] = {1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024};
  scanf("%d", &n);
  for (int i = 0; i < a[n - 1]; i++) {
    printf("a");
    int k = i;
    stack<char> s;
    while (k) {
      if (k & 1)
        s.push('b');
      else
        s.push('a');
      k >>= 1;
    }
    while (s.size() < n - 1) s.push('a');
    while (!s.empty()) printf("%c", s.top()), s.pop();
    puts("");
  }
}
