/* -*- coding: utf-8 -*-
 *
 * 275.cc: No.275 中央値を求めよ - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int MAX_N = 1000;

/* typedef */

/* global variables */

int as[MAX_N];

/* subroutines */

/* main */

int main() {
  int n;
  cin >> n;
  for (int i = 0; i < n; i++) cin >> as[i];
  sort(as, as + n);

  int r2 = (n & 1) ? as[n / 2] * 2 : as[n / 2 - 1] + as[n / 2];
  if (r2 & 1) printf("%.1lf\n", (double)r2 / 2);
  else printf("%d\n", r2 / 2);
  
  return 0;
}