#include <bits/stdc++.h>
using namespace std;
template <class A>
void pr(A a) {
  cout << a;
  cout << '\n';
}
template <class A, class B>
void pr(A a, B b) {
  cout << a << ' ';
  pr(b);
}
template <class A, class B, class C>
void pr(A a, B b, C c) {
  cout << a << ' ';
  pr(b, c);
}
template <class A, class B, class C, class D>
void pr(A a, B b, C c, D d) {
  cout << a << ' ';
  pr(b, c, d);
}
template <class A>
void PR(A a, long long n) {
  for (long long i = (long long)(0); i < (long long)(n); i++) {
    if (i) cout << ' ';
    cout << a[i];
  }
  cout << '\n';
}
long long check(long long n, long long m, long long x, long long y) {
  return x >= 0 && x < n && y >= 0 && y < m;
}
const long long MAX = 1e9 + 7, MAXL = 1LL << 61, dx[4] = {-1, 0, 1, 0},
                dy[4] = {0, 1, 0, -1};
long long solve(map<long long, long long> m) {
  long long f = 0, c = 0;
  for (__typeof((m).begin()) it = (m).begin(); it != (m).end(); it++) {
    if (it->first == 0 && it->second >= 2) return 0;
    if (it->second == 2) c++;
    if (it->second > 2) return 0;
    if (it->first == 0) continue;
    if (it->second == 2 && m.count(it->first - 1)) return 0;
    if (!m.count(it->first - 1)) f = 1;
  }
  if (c > 1) return 0;
  return f;
}
void Main() {
  long long n;
  cin >> n;
  long long a[n];
  for (long long i = (long long)(0); i < (long long)(n); i++) cin >> a[i];
  sort(a, a + n);
  map<long long, long long> m;
  for (long long i = (long long)(0); i < (long long)(n); i++) m[a[i]]++;
  if (solve(m) == 0) {
    pr("cslnb");
    return;
  }
  long long s = 0;
  for (long long i = (long long)(0); i < (long long)(n); i++) s += a[i] - i;
  if (s % 2)
    pr("sjfnb");
  else
    pr("cslnb");
}
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  Main();
  return 0;
}
