#include <iostream>
#include <vector>
#include <set>
#include <map>
#include <algorithm>
#include <cmath>
#include <string>

using namespace std;
typedef long long ll;
typedef vector<ll> vll;
typedef vector<vector<ll>> vvll;

int main(){
    int n;
    cin >> n;
    vector<ll> arr;
    for (int i=0; i<n; i++){
        int elem;
        cin >> elem;
        arr.push_back(elem);
    }
    int num_dupes = 0;
    int sum = 0;
    sort(arr.begin(), arr.end());
    for (int j=0; j<n; j++){
        if ((j + 1 < n) && (arr[j]==arr[j+1])) {
            num_dupes++;
            if (j!=0){
                if (arr[j-1]+1 == arr[j]){
                    cout << "cslnb";
                    return 0;
                }
            }
            if (arr[j] == 0){
                cout << "cslnb";
                return 0;
            }
        }
        int diff = arr[j] - j;
        if (diff < 0){
            cout << "cslnb";
            return 0;
        }
        sum += diff;
    }
    if (num_dupes>1) cout << "cslnb";
    else if (sum%2==0) cout << "cslnb";
    else cout << "sjfnb";
}