#include <bits/stdc++.h>
#pragma GCC optimize("O3")
const double PI = acos(-1);
template <class A, class B>
std::ostream& operator<<(std::ostream& st, const std::pair<A, B> p) {
  st << "(" << p.first << ", " << p.second << ")";
  return st;
}
using namespace std;
char out[][20] = {"cslnb", "sjfnb"};
int A[1 << 20], n;
int main() {
  scanf("%d", &n);
  for (int i = 0; i < (n); i++) scanf("%d", A + i);
  sort(A, A + n);
  int problems = 0;
  int c = -1;
  for (int i = 0; i < n;) {
    int j = i;
    while (j < n && A[i] == A[j]) j++;
    problems += j - i - 1;
    if (j - i - 1) c = i;
    i = j;
  }
  if (problems > 1) {
    puts(out[0]);
    return 0;
  }
  int flag = 0, d = 0;
  if (problems == 1) {
    if (A[c] == 0) {
      puts(out[0]);
      return 0;
    }
    assert(c >= 0);
    A[c]--;
    if (c && A[c] == A[c - 1]) {
      puts(out[0]);
      return 0;
    }
    flag = 1;
  }
  for (int i = 0; i < (n); i++) {
    if (A[i] < i) {
      d = 0;
      break;
    }
    d ^= (A[i] - i) & 1;
  }
  d ^= flag;
  puts(out[d]);
  return 0;
}
