#include<stdio.h>
int main()
{
int n,a[200],i,j,t,sum;
while(scanf("%d",&n)!=EOF&&n)
{
sum=0;
for(i=1;i<=n;i++)
scanf("%d",&a[i]);
for(i=1;i<=n;i++)
{
for(j=i;j<=n-1;j++)
{
if(a[j]>a[j+1])
{
t=a[j];
a[j]=a[j+1];
a[j+1]=t;
}
}
}
n=n/2+1;
for(i=1;i<=n;i++)
sum=sum+a[i]/2+1;
printf("%d\n",sum);
}
return 0;
}