#include <bits/stdc++.h>
using namespace std;
const long long maxn = 1e5 + 100;
const long long mod = 1e9 + 7;
const long long inf = 1e18;
long long n, a, s, c;
bool f;
map<long long, long long> cnt;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  ;
  cin >> n;
  for (long long i = 0; i < n; i++) {
    cin >> a;
    cnt[a]++;
    s += a;
  }
  cnt[-1] = 1;
  for (map<long long, long long>::iterator i = cnt.begin(); i != cnt.end();
       i++) {
    if (i->second > 2) f = 1;
    if (i->second == 2 && cnt[i->first - 1]) f = 1;
    c += (i->second == 2);
  }
  if (f || c > 1) {
    cout << "cslnb";
  } else {
    if ((s - n * (n - 1) / 2) % 2) {
      cout << "sjfnb";
    } else {
      cout << "cslnb";
    }
  }
  return 0;
}
