#include <bits/stdc++.h>
using namespace std;
void A() {
  cout << "sjfnb" << endl;
  exit(0);
}
void B() {
  cout << "cslnb" << endl;
  exit(0);
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int n;
  cin >> n;
  vector<int> a(n);
  for (int i = 0; i < n; ++i) {
    cin >> a[i];
  }
  sort(a.begin(), a.end());
  if (n == 1) {
    if (a[0] % 2 == 0) {
      B();
    } else {
      A();
    }
  }
  if (a[1] == 0) {
    B();
  }
  vector<int> b = a;
  if (unique(b.begin(), b.end()) - b.begin() <= n - 2) {
    B();
  }
  int t = 0;
  for (int i = 0; i < n - 1; ++i) {
    if (a[i] == a[i + 1]) {
      if (i > 0 && a[i - 1] == a[i] - 1) {
        B();
      }
      --a[i];
      t = 1;
    }
  }
  for (int i = 0; i < n; ++i) {
    t = (t + a[i] - i) % 2;
  }
  if (t % 2 == 0) {
    B();
  } else {
    A();
  }
  return 0;
}
