#include <stdio.h>

int sort(int n, int str[]);
int calMedian(int n, int str[]);

int main(void)
{
	int n;
	int str[1000];
	scanf("%d", &n);
	for (int i = 0; i < n; i++)
		scanf("%d", &(str[i]));
	//printf("%d %d %d", str[0],str[1],str[2]); test

	sort(n, str);

	calMedian(n, str);

	return 0;
}



int sort(int n, int str[])
{
	int i,j;
	int a;

	for (i = 0; i <= n - 1; i++) {
		for (j = 1; j <= n - i - 1; j++) {
			if (str[i] > str[i + j]) {
				a = str[i];
				str[i] = str[i + j];
				str[i + j] = a;
			}
		}
	}
	return 0;
}

int calMedian(int n, int str[])
{
	double a;

	if (n % 2 == 0) {
		a = (str[n / 2 -1] + str[n / 2 ]) / 2.0;
		printf("%.1f\n", a);
	}
	else {
		a = str[(n+1)/2 -1];
		printf("%.1f\n", a);

	}
	return 0;
}