#include <bits/stdc++.h>
using namespace std;
using ll = long long;
bool solve(vector<int> a) {
  const int n = a.size();
  int k = -1;
  for (int i = 0; i + 1 < n; i++) {
    if (a[i] == a[i + 1]) {
      if (k != -1) {
        return false;
      }
      k = i;
    }
  }
  if (k != -1) {
    if (k == 0) {
      if (a[k] > 0) {
        a[k]--;
        return !solve(a);
      } else
        return false;
    } else if (a[k - 1] + 1 < a[k]) {
      a[k]--;
      return !solve(a);
    } else
      return false;
  }
  ll ans = 0;
  for (int i = 0; i < (n); i++) {
    ans += a[i] - i;
  }
  return ans % 2 == 1;
}
int main() {
  cin.tie(nullptr);
  ios::sync_with_stdio(false);
  int n;
  cin >> n;
  vector<int> a(n);
  for (int i = 0; i < (n); i++) cin >> a[i];
  sort(a.begin(), a.end());
  cout << (solve(a) ? "sjfnb" : "cslnb") << endl;
}
