#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 100;
int n;
int a[N];
int main() {
  cin >> n;
  long long sum = 0;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    sum += (long long)a[i] - i;
  }
  sort(a, a + n);
  if (a[0] == a[1] && a[0] == 0) {
    cout << "cslnb\n";
    return 0;
  }
  int cnt = 0;
  for (int i = 0; i < n - 1; i++) {
    if (a[i] == a[i + 1]) {
      cnt++;
    } else if (i < n - 2 && a[i] == a[i + 1] - 1 && a[i + 1] == a[i + 2]) {
      cout << "cslnb\n";
      return 0;
    }
  }
  if (cnt >= 2) {
    cout << "cslnb\n";
    return 0;
  }
  if (sum % 2)
    cout << "sjfnb\n";
  else
    cout << "cslnb\n";
  return 0;
}
