#include <stdio.h>
int main(void){

  int A[1000];
  int N,i,k,j;

  scanf("%d",&N);

  for(i=0;i<N;i++){
    scanf("%d",&A[i]);
  }

  for(i=0;i<N;i++){
    for(j=i+1;j<N;j++){
      if(A[i]>A[j]){
        k=A[i];
        A[i]=A[j];
        A[j]=k;
      }
    }
  }

  if(N%2==1){
    printf("%d\n",A[(N-1)/2]);
  }
  else{
    printf("%.1lf\n",(A[(N-1)/2]+A[(N+1)/2])/(double)2);
  }

return 0;
}