#include <bits/stdc++.h>
using namespace std;
class Solution {
 public:
  int solve(vector<int>& nums) {
    sort(nums.begin(), nums.end());
    int n = nums.size();
    long long moves = 0;
    for (int i = 0; i + 1 < n; ++i) {
      if (nums[i] == nums[i + 1] && nums[i] > 0) {
        ++moves;
        --nums[i];
        break;
      }
    }
    for (int i = 0; i + 1 < n; ++i) {
      if (nums[i] == nums[i + 1]) {
        return 1;
      }
    }
    if (nums.back() == 0) {
      assert(moves == 0);
      return 1;
    }
    int p = -1;
    for (int i = 0; i < n; ++i) {
      p = min(p + 1, nums[i]);
      moves += nums[i] - p;
    }
    return moves % 2 == 1 ? 0 : 1;
  }
};
int main(int argc, char** argv) {
  ios::sync_with_stdio(false);
  cin.tie(0);
  Solution sol;
  int n;
  cin >> n;
  vector<int> nums(n);
  for (int i = 0; i < n; ++i) {
    cin >> nums[i];
  }
  if (sol.solve(nums) == 0) {
    cout << "sjfnb\n";
  } else {
    cout << "cslnb\n";
  }
  return 0;
}
