#include <bits/stdc++.h>
using namespace std;
int main() {
  long n, Count = 1, Double = 0;
  cin >> n;
  vector<long> A(n);
  for (long &x : A) cin >> x;
  sort(A.begin(), A.end());
  if (n >= 2 && A[1] == 0) {
    cout << "cslnb" << endl;
    return 0;
  }
  long long Sum = A[0];
  for (long i = 1; i < n; ++i) {
    Sum += A[i] - i;
    if (A[i] == A[i - 1])
      ++Count;
    else
      Count = 1;
    if (Count == 2) {
      ++Double;
      if (i >= 2 && A[i - 2] == A[i] - 1) {
        cout << "cslnb" << endl;
        return 0;
      }
    }
    if (Count >= 3 || Double >= 2) {
      cout << "cslnb" << endl;
      return 0;
    }
  }
  cout << (Sum & 1 ? "sjfnb" : "cslnb") << endl;
}
