#include <bits/stdc++.h>
using namespace std;
long long int i, j, n, m, k, l, q, t, a, b, sum[3], tot[3], cnt[3];
long long int powom(long long int a, long long int b) {
  long long int result = 1;
  while (b > 0) {
    if (b & 1) result = result * a;
    a = a * a;
    b >>= 1;
  }
  return result;
}
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  cin >> n;
  vector<long long int> v(n);
  map<long long int, long long int> mp;
  for (auto &x : v) {
    cin >> x;
    mp[x]++;
  }
  sort(v.begin(), v.end());
  bool flag = 0;
  for (auto x : mp) {
    if (x.second > 2) {
      cout << "cslnb";
      return 0;
    } else if (x.second == 2 && mp.count(x.first - 1) != 0) {
      cout << "cslnb";
      return 0;
    } else if (x.second == 2 && x.first == 0) {
      cout << "cslnb";
      return 0;
    } else if (x.second == 2) {
      if (flag) {
        cout << "cslnb";
        return 0;
      }
      flag = 1;
    }
  }
  long long int ans = 0;
  for (long long int i = 0; i < n; i++) {
    ans += (v[i] - i);
  }
  if (ans & 1) {
    cout << "sjfnb";
  } else {
    cout << "cslnb";
  }
  return 0;
}
