#include <bits/stdc++.h>
using namespace std;
int nxt() {
  int x;
  cin >> x;
  return x;
}
long long int nxtl() {
  long long int x;
  cin >> x;
  return x;
}
void SieveOfEratosthenes(int n, vector<int> &primes) {
  bool prime[n + 1];
  memset(prime, true, sizeof(prime));
  for (int p = 2; p * p <= n; p++) {
    if (prime[p] == true) {
      for (int i = p * p; i <= n; i += p) prime[i] = false;
    }
  }
  for (int p = 2; p <= n; p++)
    if (prime[p]) primes.push_back(p);
}
long long int max(long long int a, long long int b) {
  if (a > b) return a;
  return b;
}
long long int power(long long int x, long long int y, long long int mod) {
  long long int temp;
  if (y == 0) return 1;
  temp = power(x, y / 2, mod);
  if (y % 2 == 0)
    return (temp * temp) % mod;
  else
    return (((x * temp) % mod) * temp) % mod;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int n = nxt();
  map<int, int> m2;
  for (int i = 0; i < n; i++) {
    int x = nxt();
    m2[x] += 1;
  }
  int c = 0;
  long long int tot = 0;
  for (auto it = m2.begin(); it != m2.end(); it++) {
    if (it->second > 2) {
      cout << "cslnb" << endl;
      return 0;
    }
    if (it->second == 2) c++;
    if (c > 1) {
      cout << "cslnb" << endl;
      return 0;
    }
    if (it->second == 2 && m2.find(it->first - 1) != m2.end()) {
      cout << "cslnb" << endl;
      return 0;
    }
    if (it->second > 1 && it->first == 0) {
      cout << "cslnb" << endl;
      return 0;
    }
    if (it->second == 2) {
      it->second = 1;
      m2[it->first - 1] += 1;
      tot++;
    }
  }
  if (n == 1 && m2.begin()->first == 0) {
    cout << "cslnb" << endl;
    return 0;
  }
  long long int c2 = 0;
  for (auto it = m2.begin(); it != m2.end(); it++) {
    tot += (it->first - c2);
    c2++;
  }
  if (tot % 2 == 0) {
    cout << "cslnb" << endl;
    return 0;
  } else
    cout << "sjfnb" << endl;
  return 0;
}
