#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  int sum[100005];
  int num[100005];
  cin >> n;
  int s = 0;
  int ss = 0;
  map<long long, long long> mp;
  for (int i = 1; i <= n; i++) {
    cin >> sum[i];
    mp[sum[i]]++;
    if ((mp[sum[i]] == 2 && sum[i] == 0) || (mp[sum[i]] == 3)) {
      s = 1;
    }
    if (mp[sum[i]] == 2) {
      num[ss] = sum[i];
      ss++;
    }
  }
  for (int i = 0; i < ss; i++) {
    if (mp[num[i] - 1]) {
      cout << "cslnb" << endl;
      return 0;
    }
  }
  sort(sum + 1, sum + n + 1);
  int m = 0;
  int mm = 1;
  int f = 0;
  for (int i = 1; i <= n; i++) {
    if (!sum[i]) {
      f = 1;
      continue;
    } else {
      if (f) {
        m = sum[i] - 1;
        sum[i] = 1;
      } else {
        m = sum[i];
        sum[i] = 0;
      }
      mm = i;
      break;
    }
  }
  if (mm > 2 || s == 1 || ss > 1) {
    cout << "cslnb" << endl;
    return 0;
  }
  for (int i = mm + 1; i <= n; i++) {
    if (sum[i] != sum[i - 1]) {
      m += sum[i] - sum[i - 1] - 1;
      sum[i] = sum[i - 1] + 1;
    } else {
      cout << "cslnb" << endl;
      return 0;
    }
    if (m % 2 == 0) {
      m = 0;
    } else {
      m = 1;
    }
  }
  if (m % 2 == 0) {
    cout << "cslnb" << endl;
  } else {
    cout << "sjfnb" << endl;
  }
  return 0;
}
