#include <bits/stdc++.h>
#include <iostream>
#include <string>
#include <stdlib.h>
using namespace std;

int main() {

	int n;
	cin>>n;
	double a[n];
	for (int i = 0; i < n; ++i) {
		cin>>a[i];
	}
	int temp=0;
	sort(a,a+n);
	temp=floor(n/2);
	if(n%2==1){
		printf("%.1f",a[temp]);
	}else{
		printf("%.1f",(a[n/2-1]+a[n/2])/2);
	}

}