//#include <bits/stdc++.h>
#include<iostream>
#include<string.h>
#include<cstdio>
#include<algorithm>
using namespace std;
typedef __int64 LL;
const int N=1e2+10;
int n,m;
int a[N];
int main()
{
int i,j,k;
while(~scanf("%d",&n))
{
for(i=0;i<n;i++)
scanf("%d",&a[i]);
sort(a,a+n);
int sum=0;
for(i=0;i<n/2+1;i++)
sum+=a[i]/2+1;
printf("%d
",sum);
}
return 0;
}