fn getline() -> String{
        let mut __ret=String::new();
        std::io::stdin().read_line(&mut __ret).ok();
        return __ret;
}

fn main(){
        getline();
        let mut ls: Vec<i64> = getline().trim().split(' ').map(|x| x.parse().unwrap()).collect();

        ls.sort();

        if ls.len() % 2 == 0 {
                println!("{}", ((ls[ls.len()/2] + ls[ls.len()/2-1]) as f64) / 2.0);
        } else {
                println!("{}", ls[ls.len()/2]);
        }
}