#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int n;
int a[100100];
int main() {
  ios_base::sync_with_stdio(0);
  cout.tie(0);
  cin.tie(0);
  cin >> n;
  for (int i = 0; i < n; i++) cin >> a[i];
  sort(a, a + n);
  int cnt = 0;
  for (int i = 1; i < n; i++)
    if (a[i - 1] == a[i]) {
      if (a[i] == 0) {
        cout << "cslnb";
        return 0;
      }
      if (i == 1) {
        a[i - 1]--;
        cnt++;
      } else if (a[i - 1] - 1 == a[i - 2]) {
        cout << "cslnb";
        return 0;
      } else {
        a[i - 1]--;
        cnt++;
      }
    }
  if (cnt > 1) {
    cout << "cslnb";
    return 0;
  }
  ll pos = cnt;
  for (int i = 0; i < n; i++) {
    pos += a[i] - i;
  }
  cout << ((pos & 1) ? "sjfnb" : "cslnb");
  return 0;
}
