#include <bits/stdc++.h>
using namespace std;
vector<vector<long long int>> adjlist;
long long int max(long long int x, long long int y) { return (x > y) ? x : y; }
long long int min(long long int x, long long int y) { return (x > y) ? y : x; }
long long int cases = 1, n, sum, m;
long long int x, y;
void solveCase(long long int testCaseNum) {
  cin >> n;
  vector<long long int> freq(10, 1);
  long long int pos = 0, currNoOfSequences = 1;
  while (currNoOfSequences < n) {
    currNoOfSequences /= freq[pos];
    freq[pos]++;
    currNoOfSequences *= freq[pos];
    pos = (pos + 1) % 10;
  }
  cout << string(freq[0], 'c') + string(freq[1], 'o') + string(freq[2], 'd') +
              string(freq[3], 'e') + string(freq[4], 'f') +
              string(freq[5], 'o') + string(freq[6], 'r') +
              string(freq[7], 'c') + string(freq[8], 'e') + string(freq[9], 's')
       << "\n";
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  for (long long int t = 1; t <= cases; t++) {
    solveCase(t);
  }
  return 0;
}
