#include <bits/stdc++.h>
using namespace std;
int a[100001];
int main() {
  int n;
  scanf("%d", &n);
  for (int i = 1; i <= n; i++) scanf("%d", &a[i]);
  sort(a + 1, a + n + 1);
  int num = 0;
  for (int i = 1; i < n; i++)
    if (a[i + 1] == a[i])
      if ((a[i] == 0) || (i > 1 && a[i - 1] + 1 == a[i]) || ++num > 1) {
        puts("cslnb");
        return 0;
      }
  long long sum = 0;
  for (int i = 1; i <= n; i++) sum += (long long)(a[i] - i - 1);
  if (sum % 2)
    puts("sjfnb");
  else
    puts("cslnb");
  return 0;
}
