Contest1332/A.cpp

//
// Created by jal on 2019-05-02.
//

#include<bits/stdc++.h>
using namespace std;
int main(){
    int n;
    while(cin >> n){
        vector<int>v(n);
        for(auto&i:v){
            cin >> i;
        }
        sort(v.begin(), v.end());
        if(v.size()%2==0){
            cout << fixed << setprecision(2) << (v[n/2-1]+v[n/2])/2.0 << endl;
        }else{
            cout << fixed << setprecision(2) << v[n/2]/1.0 << endl;
        }
    }
}