#include <bits/stdc++.h>
using namespace std;
long long n;
long long a[100005];
int main() {
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
  }
  sort(a, a + n);
  long long nums = (n - 1) * n / 2;
  long long cnt = a[0];
  int consequtive = 0;
  int flag = 0;
  int zeros = 0;
  int hastwo = 0;
  if (a[0] == 0) zeros++;
  for (int i = 1; i < n; i++) {
    cnt += a[i];
    if (a[i] == a[i - 1]) {
      consequtive++;
      hastwo++;
    } else {
      consequtive = 0;
    }
    if (a[i] == 0) zeros++;
    if (consequtive >= 2 || zeros >= 2 ||
        (i >= 2 && consequtive == 1 && a[i] - a[i - 2] == 1) || hastwo >= 2) {
      flag = 1;
      break;
    }
  }
  if (flag || cnt <= nums || (cnt - nums) % 2 == 0) {
    cout << "cslnb" << endl;
  } else {
    cout << "sjfnb" << endl;
  }
  return 0;
}
