#include <bits/stdc++.h>
using namespace std;
const double pi = acos(-1);
const int N = 1e6 + 6, mod = 998244353, M = 1e7 + 7;
const long long MAX = 5e18;
int n, a[N];
long long sum;
bool unval(bool rp = 1) {
  for (int i = 1; i < n; i++) {
    if (a[i] == a[i - 1]) {
      if (rp && a[i] > 0) {
        a[i - 1]--;
        return unval(0);
      }
      return 1;
    }
  }
  return 0;
}
int main() {
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%d", a + i);
    sum += a[i] - i;
  }
  sort(a, a + n);
  if (unval()) return puts("cslnb");
  cout << (sum % 2 ? "sjfnb" : "cslnb");
  return 0;
}
