#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(0);
  long long n;
  cin >> n;
  long long a[n], c3 = 0, c2 = 0, p = 0;
  map<long long, long long> make_pair;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    p += a[i] - i;
    make_pair[a[i]]++;
  }
  map<long long, long long>::iterator it;
  vector<long long> v;
  for (it = make_pair.begin(); it != make_pair.end(); it++) {
    if (it->second >= 3)
      c3++;
    else if (it->second >= 2) {
      c2++;
      v.push_back(it->first);
    }
  }
  if (c3 > 0 || c2 > 1)
    cout << "cslnb";
  else {
    if (make_pair[0] > 1) {
      cout << "cslnb";
      return 0;
    }
    if (v.size() > 0 && make_pair[v[0] - 1] > 0) {
      cout << "cslnb";
      return 0;
    }
    if (p & 1)
      cout << "sjfnb";
    else
      cout << "cslnb";
  }
}
