import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.util.Arrays; public class No0275 { public static void main(String[] args) { try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in))) { int N = Integer.parseInt(br.readLine()); String[] str = br.readLine().split(" "); int[] A = new int[N]; int length = A.length; int l = length / 2; for (int i = 0; i < N ; i++) { A[i] = Integer.parseInt(str[i]); } Arrays.sort(A); if(length % 2 == 0){ System.out.println( (double)(A[l - 1] + A[l]) / 2); } else { System.out.println(A[l]); } } catch (IOException e) { e.printStackTrace(); } } }