#include <bits/stdc++.h>
using namespace std;
const long long max_ = 3e5 + 7;
long long mod = 998244353;
const long long inf = 1e9;
const long long INF = 1e18;
long long read() {
  long long s = 0, f = 1;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9') {
    s = s * 10 + ch - '0';
    ch = getchar();
  }
  return s * f;
}
inline long long min(long long a, long long b) { return a < b ? a : b; }
inline long long max(long long a, long long b) { return a > b ? a : b; }
signed main() {
  long long n = read();
  for (long long i = 1; i <= n; i++) {
    for (long long i = 1; i < n; i++) {
      cout << "a";
    }
    cout << (char)('a' + (i - 1)) << endl;
  }
}
