#include <bits/stdc++.h>

using namespace std;

const int MAXN=1e4+50;

int N,a[MAXN];

int main()
{
	scanf("%d",&N);
	for(int i=1;i<=N;i++)
	scanf("%d",&a[i]);
	sort(a+1,a+N+1);
	if(N&1)
	printf("%d",a[N/2+1]);
	else
	{
		if(a[N/2]+a[N/2+1]&1)
		printf("%.1lf",(a[N/2]+a[N/2+1])*0.50);
		else
		printf("%d",(a[N/2]+a[N/2+1])/2);
	}
}