#include <bits/stdc++.h>
using namespace std;
const int N = 1e5;
int n, cnt;
long long a[N + 5], sum;
int main() {
  scanf("%d", &n);
  for (int i = 1; i <= n; ++i) {
    scanf("%lld", &a[i]);
    sum += a[i];
  }
  if (n == 1 && a[1] == 0) return !printf("cslnb\n");
  sort(a + 1, a + n + 1);
  for (int i = 2; i <= n; ++i) {
    if (a[i] == a[i - 1]) ++cnt;
    if (i != 2 && a[i] == a[i - 1] && a[i - 2] == a[i] - 1)
      return !printf("cslnb\n");
    if (a[i] == a[i - 1] && a[i] == 0) return !printf("cslnb\n");
  }
  if (cnt > 1) return !printf("cslnb\n");
  sum -= (n - 1) * n / 2;
  if (sum <= 0) return !printf("cslnb\n");
  if (sum & 1) return !printf("sjfnb\n");
  printf("cslnb\n");
  return 0;
}
