#include <bits/stdc++.h>
using namespace std;
const int N = 2e5 + 6;
void files() {}
int main() {
  ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
  files();
  int n;
  cin >> n;
  vector<int> v(n);
  int cnt = 0;
  for (auto &i : v) cin >> i;
  sort(((v).begin()), ((v).end()));
  int dist = 0, last = v[0];
  v.push_back(1);
  for (int i = 0; i < n; ++i) {
    int f = 0, j = i - 1;
    last = v[i];
    while (i < n && v[i] == last) {
      i++;
      f++;
    }
    if (f > 2) cnt = 4;
    if (f == 2) cnt++;
    if (j >= 0 && last - v[j] == 1 && f > 1) return cout << "cslnb", 0;
    i -= i != n;
    dist++;
  }
  if (dist < n - 2 || cnt > 1) return cout << "cslnb", 0;
  long long sum = 0;
  for (int j = 0; j < n; ++j) {
    sum += v[j] - j;
    if (v[j] - j < 0) return cout << "cslnb", 0;
  }
  sum &= 1;
  sum ^= 1;
  cout << (sum ? "cslnb" : "sjfnb");
  return 0;
}
