#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1e5 + 5;
int a[MAXN];
int main() {
  int n, tot = 0, flag = -1, num = 0;
  scanf("%d", &n);
  for (int i = 0; i < n; ++i) scanf("%d", &a[i]);
  sort(a, a + n);
  for (int i = 0; i < n - 1; ++i) {
    if (i != 0 && a[i] == a[i + 1] && a[i - 1] == a[i] - 1) flag = 1;
    if (a[i] == a[i + 1]) num++;
    tot += a[i] - i;
  }
  tot += a[n - 1] - (n - 1);
  if (num >= 2) flag = 1;
  if (a[0] == 0 && a[1] == 0) flag = 1;
  if (flag == -1) {
    if (tot % 2 == 0)
      flag = 1;
    else
      flag = 0;
  }
  if (flag)
    printf("cslnb");
  else
    printf("sjfnb");
  return 0;
}
