#include <bits/stdc++.h>
using namespace std;
long long n, s;
long long f1, f2;
long long a[100005];
map<long long, long long> mp;
int main() {
  scanf("%lld", &n);
  for (int i = 1; i <= n; i++) {
    scanf("%lld", &a[i]);
    mp[a[i]]++;
    s += a[i];
  }
  if (!s) {
    printf("cslnb\n");
    return 0;
  }
  for (map<long long, long long>::iterator it = mp.begin(); it != mp.end();
       it++) {
    long long x = it->first, y = it->second;
    if (x == 0 && y > 1) {
      printf("cslnb\n");
      return 0;
    }
    if (y > 2) {
      printf("cslnb\n");
      return 0;
    }
    if (y == 2) f1++;
    if (y == 2 && mp[x - 1] > 0) f2++;
  }
  if (f1 > 1) {
    printf("cslnb\n");
    return 0;
  }
  if (f1 == 1 && f2 == 1) {
    printf("cslnb\n");
    return 0;
  }
  s -= (n * (n - 1ll) / 2ll);
  if (s % 2) {
    printf("sjfnb\n");
  } else {
    printf("cslnb\n");
  }
}
