#include <bits/stdc++.h>
#define pb push_back
#define eb emplace_back
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define uniq(x) x.erase(unique(all(x)), x.end())
#define rall(x) x.rbegin(), x.rend()
//#define int long long
using namespace std;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
const int mod = 1e9 + 7;
const int LOG = 20;
const int maxn = 1e5 + 5;
const double eps = 1e-9;
void setIO() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
}
int32_t main() {
setIO();
int n;
cin >> n;
vector<int> v(n);
for(int &x : v) cin >> x;
sort(rall(v));
ll ans = 0;
if(n < 3) {
for(int &x : v) ans += x;
cout << ans << '\n';
return 0;
}
for(int i=0; i<n; i+=3) {
ans += v[i];
if(i + 1 < n) ans += v[i+1];
}
cout << ans << '\n';
return 0;
}
