#include"median.h"
#include<vector>
#include<algorithm>
using namespace std;
double median(vector<double> vec)
{
	typedef vector<double>::size_type vec_sz;

	vec_sz size=vec.size();
	if(size==0)
		throw domain_error("median of an empty vector");
	sort(vec.begin(),vec.end());

	vec_sz mid=size/2;
	return size%2==0?(vec[mid]+vec[mid-1])/2:vec[mid];
}