#include <bits/stdc++.h>
using namespace std;
const long long inf = 1e9;
const long long base = 998244353;
const long long mod = 1e9 + 7;
bool rev = false;
void first_win() {
  if (!rev) {
    cout << "sjfnb";
    cerr << " first";
  } else {
    cout << "cslnb";
    cerr << " second";
  }
  exit(0);
}
void second_win() {
  if (!rev) {
    cout << "cslnb";
    cerr << " second";
  } else {
    cout << "sjfnb";
    cerr << " first";
  }
  exit(0);
}
int main() {
  srand(time(NULL));
  std::ios_base::sync_with_stdio(false);
  std::cin.tie(nullptr);
  auto start = clock();
  int n;
  cin >> n;
  vector<int> a(n);
  long long sum = 0;
  map<int, int> cnt, cntcnt;
  int cnt_zero = 0;
  for (int i = 0; i < n; ++i) {
    cin >> a[i];
    if (a[i] == 0) ++cnt_zero;
    sum += 1LL * a[i];
    ++cnt[a[i]];
  }
  if (n == 1) {
    if (sum % 2 == 0) {
      second_win();
    } else {
      first_win();
    }
  }
  if (sum == 0) {
    second_win();
  }
  if (n == 2) {
    if (sum % 2 == 0) {
      first_win();
    } else {
      second_win();
    }
  }
  int cnt_more_than_one = 0;
  for (auto c : cnt) {
    ++cntcnt[c.second];
    if (c.second > 2) {
      second_win();
    }
    if (c.second > 1) ++cnt_more_than_one;
  }
  if (cnt_more_than_one > 1) {
    second_win();
  }
  if (cnt_zero > 1) {
    second_win();
  }
  int twice = -1;
  for (auto c : cnt) {
    if (c.second > 1) {
      twice = c.first;
      break;
    }
  }
  if (twice != -1) {
    if (!cnt.count(twice - 1)) {
      cnt[twice - 1] = 1;
      cnt[twice] = 1;
    } else {
      second_win();
    }
    rev = true;
    sum -= 1;
  }
  cntcnt.clear();
  for (auto c : cnt) {
    ++cntcnt[c.second];
  }
  long long need_sum = 1LL * n * (n - 1) / 2;
  if ((sum - need_sum) % 2 == 0) {
    second_win();
  } else {
    first_win();
  }
  std::cerr << double(clock() - start) / CLOCKS_PER_SEC << std::endl;
  return 0;
}
