#include <bits/stdc++.h>
using namespace std;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  ;
  int n;
  cin >> n;
  ;
  long long int arr[n];
  for (int i = 0; i < n; i++) {
    cin >> arr[i];
  }
  sort(arr, arr + n);
  long long int tot = 0, cont = 0, prev = -1, tws = 0;
  for (int i = 0; i < n; i++) {
    if (arr[i] == prev) {
      cont++;
      if (cont == 2) {
        tws++;
        if (arr[i - 2] == prev - 1) {
          tot = 0;
          break;
        }
      }
      if (cont == 3) {
        tot = 0;
        break;
      }
    } else {
      cont = 1;
      prev = arr[i];
    }
    if (i > arr[i]) {
      tot = 0;
      break;
    }
    tot += arr[i] - i;
  }
  if (tot % 2 && tws < 2)
    cout << "sjfnb" << endl;
  else
    cout << "cslnb" << endl;
}
