#include <bits/stdc++.h>
using namespace std;
template <class T>
inline void _read(T &x) {
  x = 0;
  char tmp = getchar();
  while (!isdigit(tmp)) tmp = getchar();
  while (isdigit(tmp)) {
    x = x * 10 + tmp - '0';
    tmp = getchar();
  }
}
int n;
const int MAXN = 1e6 + 10;
long long a[MAXN];
map<int, int> s;
int main() {
  _read(n);
  for (int i = 1; i <= n; ++i) _read(a[i]);
  stable_sort(a + 1, a + n + 1);
  if (n >= 2 && a[1] == 0 && a[2] == 0) return puts("cslnb"), 0;
  int cnt = 0;
  for (int i = 1; i < n; ++i) cnt += a[i] == a[i + 1];
  if (cnt >= 2) return puts("cslnb"), 0;
  int num = 0;
  if (cnt == 1) {
    for (int i = 2; i < n; ++i)
      if (a[i] == a[i + 1] && a[i - 1] == a[i] - 1) return puts("cslnb"), 0;
    for (int i = 1; i < n; ++i) {
      if (a[i] == a[i + 1]) {
        --a[i];
        num ^= 1;
        break;
      }
    }
  }
  for (int i = n; i > 1; --i) a[i] -= a[i - 1] + 1;
  for (int i = n; i > 0; i -= 2) num += a[i] & 1;
  if (num & 1)
    puts("sjfnb");
  else
    puts("cslnb");
  return 0;
}
