#include <bits/stdc++.h>
using namespace std;
map<int, int> mp;
int a[100005];
int n;
int main() {
  int i;
  cin.tie(0);
  cout.tie(0);
  ios_base::sync_with_stdio(0);
  cin >> n;
  for (i = 1; i <= n; i++) {
    cin >> a[i];
    mp[a[i]]++;
  }
  bool ok = 1;
  if (mp[0] >= 2) ok = 0;
  int cnt = 0;
  for (auto &k : mp) {
    if (k.second >= 3) ok = 0;
    if (k.second >= 2) cnt++;
    if (k.second >= 2 && mp[k.first - 1] > 0) ok = 0;
  }
  if (cnt >= 2) ok = 0;
  if (ok == 0) {
    cout << "cslnb";
    return 0;
  }
  sort(a + 1, a + n + 1);
  long long s = 0;
  for (i = 1; i <= n; i++) {
    s += a[i] - (i - 1);
  }
  if (s % 2)
    cout << "sjfnb";
  else
    cout << "cslnb";
  return 0;
}
