#include <bits/stdc++.h>
using namespace std;
const int MOD = 998244353;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int n;
  cin >> n;
  vector<int> v(n);
  for (int& i : v) cin >> i;
  if (n == 1) {
    cout << (v[0] % 2 ? "sjfnb" : "cslnb");
    return 0;
  }
  map<int, int> m;
  m[0] = 0;
  for (int i : v) m[i]++;
  int tct = 0;
  for (auto p : m) {
    if (p.second > 2) {
      cout << "cslnb";
      return 0;
    }
    if (p.second == 2) tct++;
  }
  if (tct > 1 || m[0] > 1) {
    cout << "cslnb";
    return 0;
  }
  for (auto p : m) {
    if (p.second == 2) {
      auto it = m.find(p.first - 1);
      if (it != m.end() && it->second > 0) {
        cout << "cslnb";
        return 0;
      }
    }
  }
  sort(v.begin(), v.end());
  int par = 0;
  for (int i = 0; i < n; i++) {
    par += (v[i] - i) % 2;
  }
  par %= 2;
  cout << (par ? "sjfnb" : "cslnb");
  return 0;
}
