#include <bits/stdc++.h>
using namespace std;
const int oo = 1e9 + 9;
const long long inf = 1e18 + 18;
const int max6 = 1e6 + 6;
const int modx = 1e9 + 123;
const int mody = 997;
const int base = 137;
int a[max6];
int main() {
  int n;
  cin >> n;
  for (int i = 1; i <= n; ++i) cin >> a[i];
  sort(a + 1, a + n + 1);
  int cnt = 0;
  int i = 1;
  while (i <= n) {
    int last = upper_bound(a + 1, a + n + 1, a[i]) - a;
    if (last - i == 2) {
      cnt++;
      if (a[lower_bound(a + 1, a + n + 1, a[i] - 1) - a] == a[i] - 1) {
        cout << "cslnb";
        return 0;
      }
    }
    if (last - i >= 3 || cnt >= 2) {
      cout << "cslnb";
      return 0;
    }
    i = last;
  }
  if (a[1] == 0 && a[2] == 0) {
    cout << "cslnb";
    return 0;
  }
  int trash = 0;
  for (int i = 1; i <= n; ++i) trash = (trash + a[i] - i + 1) % 2;
  cout << (trash ? "sjfnb" : "cslnb");
}
