#include <bits/stdc++.h>
using namespace std;
void init_code() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
}
int main() {
  init_code();
  long long n;
  cin >> n;
  long long a[n];
  set<long long> s;
  long long sum = 0;
  for (long long i = 0; i < n; i++) {
    cin >> a[i];
    sum += a[i];
    s.insert(a[i]);
  }
  long long flag = 1;
  sort(a, a + n);
  for (long long i = 0; i < n; i++)
    if (a[i] == i - 1) flag = 0;
  long long flag2 = 1;
  for (long long i = 2; i < n; i++) {
    if (a[i] == a[i - 1] && (a[i] - a[i - 2] == 1)) flag2 = 0;
  }
  if (s.size() == n || ((s.size() == n - 1) && flag) && flag2) {
    long long val = sum - n * (n - 1) / 2;
    if (val & 1)
      cout << "sjfnb";
    else
      cout << "cslnb";
  } else {
    cout << "cslnb";
  }
}
