#include <bits/stdc++.h>
#pragma GCC optimize("O3")
#pragma GCC target("avx2")
using namespace std;
const double EPS = 0.0000000001;
const long long mod1 = 998244353;
const long long mod2 = 1000000007;
const long long mod3 = 1000000009;
const long long inf = 1000000000000000000;
signed main() {
  long long n;
  cin >> n;
  long long mass[n];
  for (long long i = 0; i < n; i++) cin >> mass[i];
  map<long long, long long> m;
  for (long long i = 0; i < n; i++) m[mass[i]]++;
  bool b = 0;
  for (map<long long, long long>::iterator it = m.begin(); it != m.end();
       it++) {
    pair<long long, long long> p = *it;
    if (p.second > 2 || p.second == 2 && !p.first) {
      cout << "cslnb";
      return 0;
    }
    if (p.second == 2) {
      if (b) {
        cout << "cslnb";
        return 0;
      }
      b = 1;
    }
    if (p.second == 2 && m[p.first - 1]) {
      cout << "cslnb";
      return 0;
    }
  }
  long long c = n * (n - 1) / 2;
  long long s = 0;
  for (long long i = 0; i < n; i++) s += mass[i];
  cout << ((s - c) & 1 ? "sjfnb" : "cslnb");
}
