#include <bits/stdc++.h>
using namespace std;
const long long N = 1e9 + 7;
int32_t main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  long long k;
  cin >> k;
  map<char, long long> mp;
  string s = "codefOrCEs";
  for (auto x : s) {
    mp[x] = 1;
  }
  long long p = 1;
  while (p < k) {
    for (auto x : s) {
      p = p / mp[x];
      mp[x]++;
      p = p * mp[x];
      if (p >= k) break;
    }
  }
  for (auto x : s) {
    char c = x;
    if (c < 97) {
      c = c + 32;
    }
    for (long long i = 1; i <= mp[x]; i++) {
      cout << c;
    }
  }
}
