#include <iostream>
#include <algorithm>
using namespace std;
int n,a[1000];
int main(){
    cin>>n;
    for(int i=0;i<n;i++)cin>>a[i];
    sort(a,a+n);
    if(n%2)cout<<a[n/2]<<endl;
    else cout<<(a[n/2]+a[n/2-1])/2.0<<endl;
    return 0;
}