#include<map>
#include<queue>
#include<time.h>
#include<limits.h>
#include<cmath>
#include<ostream>
#include<iterator>
#include<set>
#include<stack>
#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
#define rep_1(i,m,n) for(int i=m;i<=n;i++)
#define mem(st) memset(st,0,sizeof st)
int read()
{
int res=0,ch,flag=0;
if((ch=getchar())=='-') //判断正负
flag=1;
else if(ch>='0'&&ch<='9') //得到完整的数
res=ch-'0';
while((ch=getchar())>='0'&&ch<='9')
res=res*10+ch-'0';
return flag?-res:res;
}
typedef long long ll;
typedef pair<int,int> pii;
typedef unsigned long long ull;
typedef pair<double,double> pdd;
const int inf = 0x3f3f3f3f;
ll k,arr[11] = {0},sum = 0,m = 1;
char str[12] = {" codeforces"};
signed main()
{
cin >> k;
vector<char> v[11];
while(sum < k)
{
sum = 1;
v[m].push_back(str[m]);//存储每一个字符
arr[m]++;
m == 10 ? m = 1 : m++;
for(int i = 1; i <= 10; i++)
sum *= arr[i]; //算个数
}
for(int i = 1; i <= 10; i++)
for(int j = 0; j < v[i].size(); j++)
cout << v[i][j];
return 0;
}