#include<stdio.h>
void main()
{
	int i,N,v[N],a,j;
	float sum=0.0;
	scanf("\n%d",&N);
	for (i=0;i<N-1;i++)
	{
		scanf("%d",&v[i]);
	}
	for (i=0;i++;i<N-1)
	{
		for(j=i+1;j<N;j++)
		{
			if( v[i]>v[j] )
			{	a=v[j];
				v[j] = v[i];
				v[i]=a;
			}
		}
	}
	for(i=0;i<N;i++)
	{
		printf("\n%d",v[i]);
	}
	sum=(float) v[0]/2+(float)v[1]/2;
	for(i=2;i<N;i++)
	{
		sum=sum/2+(float)v[i]/2;
	}
	printf("\n%f",sum);
}


