#include <bits/stdc++.h>
using namespace std;
long long ara[300100];
int main() {
  long long n, m, k;
  cin >> n;
  long long orr = 0, xorr = 0, cnt = 0, mn = 1e18;
  long long x;
  for (int i = 1; i <= n; i++) {
    cin >> x;
    ara[i] = x;
  }
  bool first = true;
  sort(ara + 1, ara + n + 1);
  int cnt_two = 0;
  for (int i = 2; i <= n; i++) {
    if (i > 2 && ara[i - 2] == ara[i - 1] && ara[i - 1] == ara[i]) {
      first = false;
    } else if (ara[i - 1] == ara[i]) {
      cnt_two++;
      if (ara[i] == 0 || cnt_two > 1 || (i > 2 && ara[i - 2] + 1 == ara[i])) {
        first = false;
      }
    }
  }
  long long streak = 0, cum = 0;
  for (int i = 1; i <= n; i++) {
    if (streak > ara[i]) continue;
    cum += (ara[i] - streak);
    streak++;
  }
  if (first) {
    first = (cum & 1);
  }
  if (first) {
    cout << "sjfnb" << endl;
  } else {
    cout << "cslnb" << endl;
  }
}
