#include <stdio.h>
#include <stdlib.h>
int main()
{
    int a,i=0,s[100],u,j,t;
    double x,y,n;
    scanf("%d",&a);
    for(i=0;i<a;i++)
    {
        scanf("%d",&s[i]);
    }
    if(a%2==0)
    {
        for(i=0;i<a-1;i++)
        {
            for(j=i+1;j<a;j++)
            {
                if(s[i]>s[j])
                {
                    t=s[i];
                    s[i]=s[j];
                    s[j]=t;
                }
            }
        }
        x=s[a/2-1];
        y=s[a/2];
        printf("%.1f",(x+y)/2);
    }
    else  if(a%2==1)
    {
        for(i=0;i<a-1;i++)
        {
            for(j=i+1;j<a;j++)
            {
                if(s[i]>s[j])
                {
                    t=s[i];
                    s[i]=s[j];
                    s[j]=t;
                }
            }
        }
        u=(a-1)/2;
        n=s[u];
        printf("%.1f",n);
    }
    return 0;
}
/**************************************************************
	Problem: 1233
	User: admin
	Language: C
	Result: Accepted
	Time:10 ms
	Memory:1144 kb
****************************************************************/