#include <bits/stdc++.h>
using namespace std;
template <typename T>
inline void read(T& x) {
  bool Neg = false;
  char c;
  for (c = getchar(); c<'0' | c> '9'; c = getchar())
    if (c == '-') Neg = !Neg;
  x = c - '0';
  for (c = getchar(); c >= '0' && c <= '9'; c = getchar()) x = x * 10 + c - '0';
  if (Neg) x = -x;
}
template <typename T>
inline void write(T x) {
  if (x < 0) {
    putchar('-');
    x = -x;
  }
  T p = 1;
  for (T temp = x / 10; temp > 0; temp /= 10) p *= 10;
  for (; p > 0; x %= p, p /= 10) putchar(x / p + '0');
}
long long a[1000], k, i, j, l;
char b[10] = {'c', 'o', 'd', 'e', 'f', 'o', 'r', 'c', 'e', 's'};
bool ok() {
  long long kq = 1;
  for (long long ii = 0; ii <= 9; ii++) {
    kq *= a[ii];
  }
  return kq >= k;
}
int main() {
  read(k);
  for (i = 0; i <= 9; i++) {
    a[i] = 1;
  }
  for (;;) {
    for (i = 0; i <= 9; i++) {
      if (ok()) {
        for (j = 0; j <= 9; j++) {
          for (l = 1; l <= a[j]; l++) {
            cout << b[j];
          }
        }
        return 0;
      } else {
        a[i]++;
      }
    }
  }
}
