#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int INF = 0x3f3f3f3f;
int n, a[100005], cnt = 0;
ll s = 0;
int main() {
  memset(a, -1, sizeof(a));
  ios::sync_with_stdio(0);
  cin.tie(0);
  cin >> n;
  for (auto i = (0); i < (n); ++i) cin >> a[i];
  sort(a, a + n);
  if (!a[0] && !a[1]) {
    cout << "cslnb";
    return 0;
  }
  for (auto i = (0); i < (n); ++i) {
    s += a[i] - i;
    if (a[i] == a[i + 1]) {
      ++cnt;
      if (i && a[i] - a[i - 1] == 1) ++cnt;
    }
  }
  if (cnt > 1 || s % 2 == 0)
    cout << "cslnb";
  else
    cout << "sjfnb";
}
