#include <bits/stdc++.h>
using namespace std;
using pii = pair<long long, long long>;
template <class T>
bool minimize(T& a, const T& b) {
  return b < a ? a = b, 1 : 0;
}
template <class T>
bool maximize(T& a, const T& b) {
  return a < b ? a = b, 1 : 0;
}
const long long maxn = 2e6 + 5;
const long long base = 1007;
const long long mod[2] = {1000000007, 1000000009};
int32_t main() {
  cin.tie(nullptr)->sync_with_stdio(false);
  long long n;
  cin >> n;
  long long p = 1, k = 1;
  while (pow(k, 10) <= n) {
    p = k++;
  }
  char s[] = {'c', 'o', 'd', 'e', 'f', 'o', 'r', 'c', 'e', 's'};
  vector<long long> a(10, p);
  long long i = 0;
  if (pow(p, 10) < n) {
    long long cnt = pow(p, 10);
    while (cnt < n) {
      cnt /= p;
      a[i++] = p + 1;
      cnt *= (p + 1);
    }
  }
  for (long long i = 0; i < 10; ++i) {
    for (long long j = 0; j < a[i]; ++j) cout << s[i];
  }
  return 0;
}
