#include <bits/stdc++.h>
using namespace std;
template <typename T1, typename T2>
inline void chkmin(T1 &x, T2 y) {
  if (x > y) x = y;
}
template <typename T1, typename T2>
inline void chkmax(T1 &x, T2 y) {
  if (x < y) x = y;
}
const string FILENAME = "input";
const int MAXN = 100228;
int n;
int a[MAXN];
map<int, int> cnt;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
  }
  for (int i = 0; i < n; i++) {
    cnt[a[i]]++;
  }
  for (auto x : cnt) {
    if (x.second >= 3) {
      cout << "cslnb\n";
      exit(0);
    }
  }
  if (cnt[0] == n) {
    cout << "cslnb\n";
    exit(0);
  }
  int cnts = 0;
  for (auto x : cnt) {
    if (x.second >= 2) {
      cnts++;
    }
  }
  if (cnts >= 2) {
    cout << "cslnb\n";
    exit(0);
  }
  if (cnt[0] >= 2) {
    cout << "cslnb\n";
    exit(0);
  }
  for (auto x : cnt) {
    if (x.second >= 2) {
      if (cnt[x.first - 1] >= 1) {
        cout << "cslnb\n";
        exit(0);
      }
    }
  }
  long long sum = 0;
  long long sum1 = 0;
  for (int i = 0; i < n; i++) {
    sum += i;
    sum1 += a[i];
  }
  if (sum1 >= sum && (sum1 - sum) & 1) {
    cout << "sjfnb\n";
    exit(0);
  }
  cout << "cslnb\n";
  return 0;
}
