#include<bits/stdc++.h>
using namespace std;
int main(){
	int n,i,l,a[101];
	float x;
	cin>>n;
	for(i=0;i<n;i++){
		cin>>a[i];
	}
	for(l=n-1;l>=1;l--){
		for(i=0;i<l;i++){
			if(a[i]>a[i+1]){
				swap(a[i],a[i+1]);
			}
		}
	}
	for(i=0;i<n;i++){
		if(n%2==0){
			x=(a[n/2-1]+a[n/2])/2.0;
		}else{
			x=a[n/2];
		}
	}
	printf("%.1f",x);
}

/**************************************************************
	Problem: 1233
	User: chenjunlin
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2076 kb
****************************************************************/