#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
#define SIZE(x) (int)(x).size()
#define ALL(x) (x).begin(),(x).end()
#define ff first
#define ss second
inline ll readi(){
ll x=0,f=1;char ch=getchar();
while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
return x*f;
}
int main(){
int N=readi();
vector<int> c(N);
for(int i=0;i<N;i++){
c[i]=readi();
}
sort(c.begin(),c.end());
reverse(c.begin(),c.end());
ll ans=0;
while(SIZE(c)%3) {
ans+=c.back();
c.pop_back();
}
while(SIZE(c)){
c.pop_back();
ans+=c.back();
c.pop_back();
ans+=c.back();
c.pop_back();
}
cout<<ans<<endl;
return 0;
}
