#include <bits/stdc++.h>
using namespace std;
const int maxn = 100005;
int n;
int a[maxn];
long long tot;
map<int, int> cnt;
int main() {
  scanf("%d", &n);
  for (int i = 1; i <= (n); i++) {
    scanf("%d", &a[i]);
    tot += a[i];
    cnt[a[i]]++;
  }
  int id = -1;
  for (map<int, int>::iterator it = cnt.begin(); it != cnt.end(); it++) {
    if (it->second >= 3) {
      puts("cslnb");
      return 0;
    }
    if (it->second == 2) {
      if (id >= 0) {
        puts("cslnb");
        return 0;
      }
      id = it->first;
    }
  }
  if (id == 0 || cnt.count(id - 1)) {
    puts("cslnb");
    return 0;
  }
  sort(a + 1, a + 1 + n);
  a[0] = -1;
  for (int i = 1; i <= (n); i++) {
    a[i] = min(a[i], a[i - 1] + 1);
    tot -= a[i];
  }
  puts(tot & 1 ? "sjfnb" : "cslnb");
  return 0;
}
