#include <bits/stdc++.h>
using namespace std;
map<int, int> mp;
map<int, int>::iterator it;
int main() {
  int n;
  int x;
  scanf("%d", &n);
  while (n--) {
    scanf("%d", &x);
    mp[x]++;
  }
  int a, b, cnt = 0, pre = 0, cur = 0;
  long long p = 0;
  it = mp.begin();
  bool ch = true;
  while (it != mp.end() && ch) {
    a = it->first;
    b = it->second;
    if (b > 2) ch = false;
    if (b == 2) {
      if (pre == a)
        ch = false;
      else
        cnt++;
      if (cnt > 1) ch = false;
    }
    p += a - cur;
    cur++;
    if (b == 2) {
      p += a - cur;
      cur++;
    }
    pre = a + 1;
    it++;
  }
  if (ch == false)
    cout << "cslnb" << endl;
  else {
    if (p % 2)
      cout << "sjfnb" << endl;
    else
      cout << "cslnb" << endl;
  }
  return 0;
}
