#include<bits/stdc++.h>
#define REP(i,n) for(int i=0;i<(int)(n);i++)
using namespace std;
typedef long long int ll;
int main()
{
  int N,A[1001];
  cin >> N;
  REP(i,N)cin >> A[i];
  sort(A,A+N);
  if(N%2)cout << A[N/2] << endl;
  else cout << (1.*A[N/2-1]+A[N/2])/2.0 << endl;
  
  return 0;
}