#include <bits/stdc++.h>
#define  Rep(i,j,n) for(li i=(j);i<(n);i++)
#define  rep(i,n) Rep(i,0,n) 
using namespace std;
typedef long int li;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<string> vs;

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