#include <bits/stdc++.h>
int a[200000], b[200000];
std::map<int, int> cnt;
int main() {
  int QAQ = 0;
  int n;
  scanf("%d", &n);
  for (int i = 1; i <= n; i++) {
    scanf("%d", &a[i]);
    cnt[b[i] = a[i]]++;
  }
  int orz = 0;
  std::sort(b + 1, b + n + 1);
  int m = std::unique(b + 1, b + n + 1) - b - 1;
  for (int i = 1; i <= m; i++) {
    if (cnt[b[i]] > 2) {
      puts("cslnb");
      return 0;
    }
    if (cnt[b[i]] == 2) {
      orz++;
      if (b[i]) {
        cnt[b[i]]--;
        cnt[b[i] - 1]++;
        if (cnt[b[i] - 1] >= 2) {
          puts("cslnb");
          return 0;
        }
        cnt[b[i]]++;
        cnt[b[i] - 1]--;
      } else {
        puts("cslnb");
        return 0;
      }
    }
  }
  if (orz > 1) {
    puts("cslnb");
    return 0;
  }
  for (int i = 1; i <= n; i++) {
    QAQ ^= ((i - 1 + a[i]) & 1);
  }
  puts(QAQ ? "sjfnb" : "cslnb");
}
