> #include <stdio.h>
> #include <algorithm>
> 
> using namespace std;
> 
> int N;
> int D[250000];
> 
> int main (){
> 	int i;
> 	
> 	scanf ( "%d", &N );
> 	for (i=0; i<N; i++) scanf ( "%d", &D[i] );
> 	
> 	sort ( D, D+N );
> 	
> 	if (N%2) printf ( "%d", D[N/2] );
> 	else{
> 		if ((D[N/2]+D[N/2-1])%2==0) printf ( "%d", (D[N/2]+D[N/2-1])/2 );
> 		else printf ( "%.1lf", (double)(D[N/2]+D[N/2-1])/2 );
> 	}
> 	
> 	return 0;
> }