#include <iostream>
#include <string>
#include <vector>
#include <cmath>
#include <algorithm>
#include <cstdlib>
#include <ctime>
#include <cstdio>
#include <functional>
#include <set>
#include <sstream>
#include <map>
#include <queue>
#include <stack>

using namespace std;


int main()
{

    int n;
    cin>>n;
    vector<int> v(n);
    for(int i=0;i<n;i++) cin>>v[i];
    sort(v.begin(),v.end());
    
    if(n%2) cout<<v[n/2]<<endl;
    else cout<<(v[n/2-1]+v[n/2])/2.0<<endl;

    return 0;
}