#include <bits/stdc++.h>
typedef long long ll;
using namespace std;

const int INF = 1e9;
const int MOD = 1e9+7;
const ll LINF = 1e18;

using pii = pair<int,int>;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) for(int i=0;i<(n);++i)
#define COUT(x) cout<<(x)<<"\n"
#define COUT15(x) cout << fixed << setprecision(15) << (x) << "\n";  

int main(){
    int n;
    cin >> n;
    vector<int> a(n);
    REP(i,n) cin >> a[i];
    sort(a.begin(),a.end());
    if(n%2!=0)COUT(a[n/2]);
    else COUT((a[n/2-1]+a[n/2])/2.0);
}