#include<bits/stdc++.h>

using namespace std;
using ll=long long;
#define rep2(i, a, n) for(int i = (a); i < (n); i++)
#define rep(i, n) rep2(i,0,n)

int main(){
  cin.tie(nullptr);ios_base::sync_with_stdio(false);
  int n;cin>>n;
  int a[n];rep(i,n)cin>>a[i];
  sort(a,a+n);
  cout<<(n%2==0?(double)(a[n/2-1]+a[n/2])/2:a[n/2])<<endl;
}