#include <stdio.h>
#include <stdbool.h>

void store_nums(double *p, int);
void bubble_sort(double *p, int);
void swap(double *xp, double *yp);
void print_median(double *p, int);

int main(void)
{
  int n;
  double nums[2000];

  scanf("%d\n", &n);

  store_nums(nums, n);
  bubble_sort(nums, n);
  print_median(nums, n);

  return 0;
}

void store_nums(double *arr, int n)
{
  for (int i = 0; i < n; ++i) {
    scanf("%lf", &arr[i]);
  }
}

void bubble_sort(double *arr, int n)
{
  bool swapped;

  for (int i = 0; i < n-1; ++i) {
    swapped = false;
    for (int j = 0; j < n-i-1; ++j) {
      if (arr[j] > arr[j+1]) {
        swapped = true;
        swap(&arr[j], &arr[j+1]);
      }
    }
    if (swapped == false) {
      break;
    }
  }
}

void swap(double *xp, double *yp)
{
  int temp = *xp;
  *xp = *yp;
  *yp = temp;
}

void print_median(double *arr, int n)
{
  printf("%f\n", (n % 2 == 0) ? ((arr[n/2] + arr[n/2-1]) / 2) : arr[n/2]);
}