#include <bits/stdc++.h>
using namespace std;
#define all(x) x.begin(),x.end()
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
template<class T> inline bool chmax(T&a,T b){if(a<b){a=b;return 1;}return 0;}
template<class T> inline bool chmin(T&a,T b){if(a>b){a=b;return 1;}return 0;}
using ll = long long;

int n;
int a[100005];

int main(){
    cin >> n;
    rep(i,n) cin >> a[i];
    sort(a,a+n);
    if(n%2==0) cout << (a[n/2-1]+a[n/2])/2.0 << endl;
    else cout << a[n/2] << endl;
}