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

//--------------------------------------------
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define RFOR(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define REP(i,n) FOR(i,0,n)
#define RREP(i,n) RFOR(i,0,n)
#define LL long long
#define INF INT_MAX/3

//--------------------------------------------
const double EPS = 1e-14;
const double PI  = acos(-1.0);

//--------------------------------------------

int main(){
  int n;
  int a[1010];

  scanf("%d",&n);
  REP (i,n) scanf("%d",&a[i]);
  sort(a, a + n);
  if (n % 2 == 1) printf("%d\n",a[n / 2]);
  else printf("%.1lf\n",double(a[(n / 2) - 1] + a[n / 2]) / 2);
}