#include <bits/stdc++.h>
using namespace std;
int main() {
  long long n, a, I = 0;
  cin >> n;
  long long S = n * (n - 1) / 2, S1 = 0;
  int k = 0;
  map<int, int> Ma;
  for (int i = 0; i < n; i++) {
    cin >> a;
    S1 += a;
    Ma[a]++;
  }
  for (map<int, int>::iterator it = Ma.begin(); it != Ma.end(); it++) {
    if (it->second >= 2) {
      k++;
      a = it->first;
      if (I != 0) {
        it--;
        if (a - it->first == 1) {
          k++;
        }
        it++;
      }
    }
    if (it->second >= 3) {
      k++;
    }
    I++;
  }
  if (k >= 2 || S1 == 0 || S1 <= S || Ma[0] > 1) {
    cout << "cslnb";
    return 0;
  }
  if ((S1 - S) % 2 == 0) {
    cout << "cslnb";
    return 0;
  }
  cout << "sjfnb";
  return 0;
}
