#include <iostream>
#include <vector>
#include <math.h>
#include <stdio.h>
#include <algorithm>
#include <string>
#include <map>
using namespace std;
#define ll long long

int main() {
  int N;
  cin >> N;
  int A[N];
  for(int i = 0; i < N; i++) {
    cin >> A[i];
  }
  sort(A,A+N);
  if(N % 2 == 0) {
    cout << (A[N/2-1] + A[N/2])/2.0 << endl; 
  }
  else {
    cout << A[N/2] << endl;
  }
}