#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using ll=long long;
using vll=vector<ll>;
using pll=pair<ll,ll>;


int main()
{
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
    ll N;
    cin>>N;
    vll a(N+1);
    for(int i=1;i<=N;++i)cin>>a[i];
    sort(a.begin()+1,a.end());
    if(N%2==1)cout<<a[(N+1)/2]<<endl;
    else cout<<(a[N/2]+a[N/2+1])/2.0<<endl;
}