#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 100;
long long n, sum, arr[N], cnt;
int main() {
  scanf("%lld", &n);
  for (int i = 0; i < n; ++i) {
    scanf("%lld", &arr[i]);
    sum += arr[i];
  }
  sort(arr, arr + n);
  for (int i = 0; i < n - 1; ++i) {
    if (arr[i] == arr[i + 1]) {
      cnt++;
      if (i && arr[i - 1] == arr[i] - 1) return puts("cslnb"), 0;
      if (cnt > 1) return puts("cslnb"), 0;
      if (arr[i] == 0) return puts("cslnb"), 0;
    }
  }
  sum -= n * (n - 1) / 2;
  if (sum & 1)
    puts("sjfnb");
  else
    puts("cslnb");
}
