#include <bits/stdc++.h>
using namespace std;
char buf[(1 << 22)], *p1 = buf, *p2 = buf;
inline int read() {
  char c =
      (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 22, stdin), p1 == p2)
           ? EOF
           : *p1++);
  int x = 0, f = 1;
  while (c<'0' | c> '9') {
    if (c == '-') f = -1;
    c = (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 22, stdin), p1 == p2)
             ? EOF
             : *p1++);
  }
  while (c >= '0' && c <= '9')
    x = x * 10 + c - '0',
    c = (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 22, stdin), p1 == p2)
             ? EOF
             : *p1++);
  return x * f;
}
const int maxn = 1e5 + 10;
int a[maxn], n;
map<int, int> mp;
map<int, bool> vis;
int main() {
  long long sum = 0;
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%d", &a[i]);
    mp[a[i]]++;
  }
  sort(a, a + n);
  int tot = 0;
  for (int i = 0; i < n; i++) {
    sum += (a[i] - i);
    if (!vis[a[i]] && mp[a[i]] > 1) {
      vis[a[i]] = true;
      tot++;
    }
    if (mp[a[i]] > 2) {
      sum = 0;
      break;
    }
    if (mp[a[i] + 1] > 1) {
      sum = 0;
      break;
    }
  }
  if (tot > 1 || mp[0] > 1) sum = 0;
  printf(sum % 2 == 0 ? "cslnb\n" : "sjfnb\n");
  return 0;
}
