#include <bits/stdc++.h>
using namespace std;
int read() {
  int x = 0, f = 1;
  char c = getchar();
  while (c < '0' || c > '9') {
    if (c == '-') f = -1;
    c = getchar();
  }
  while (c >= '0' && c <= '9')
    x = (x << 3) + (x << 1) + (c ^ 48), c = getchar();
  return x * f;
}
int N, P[100000 + 5];
int main() {
  P[0] = -1;
  N = read();
  for (int i = 1; i <= N; i++) P[i] = read();
  sort(P + 1, P + N + 1);
  bool flag = 0;
  long long tot = 0;
  for (int i = 1; i <= N; i++) {
    tot += P[i] - i + 1;
    if (P[i] == P[i + 1]) {
      if (flag || P[i] == P[i - 1] + 1) return puts("cslnb"), 0;
      flag = 1;
    }
  }
  puts((tot % 2 == 1) ? "sjfnb" : "cslnb");
}
