#include <bits/stdc++.h>
using namespace std;
using ll = long long;
constexpr char kFirstPlayer[] = "sjfnb";
constexpr char kSecondPlayer[] = "cslnb";
int main() {
  int n;
  scanf("%d", &n);
  vector<int> arr(n);
  for (int i = 0; i < n; ++i) {
    scanf("%d", &arr.at(i));
  }
  bool first_lose = false;
  bool invert_result = false;
  sort(arr.begin(), arr.end());
  for (int i = 1; i < n; ++i) {
    if (arr.at(i - 1) == arr.at(i)) {
      --arr.at(i - 1);
      invert_result = true;
      break;
    }
  }
  for (int i = 0; i < n; ++i) {
    if (arr.at(i) < 0) {
      first_lose = true;
      break;
    }
    if (i > 0 && arr.at(i) == arr.at(i - 1)) {
      first_lose = true;
      break;
    }
  }
  if (first_lose) {
    puts(kSecondPlayer);
    return 0;
  }
  int accumulate = 0;
  for (int i = 0; i < n; ++i) {
    accumulate = ((accumulate + arr.at(i) - i) & 1);
  }
  const bool first_win = invert_result ^ (accumulate % 2 == 1);
  puts(first_win ? kFirstPlayer : kSecondPlayer);
  return 0;
}
