/** made by amunduzbaev **/
#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define ll long long
#define ld long double
#define pii pair<int, int>
#define pll pair<ll, ll>
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(),x.rend()
#define fastios ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define vll vector<ll>
#define vii vector<int>
#define vpii vector<pii>
#define vpll vector<pll>
const int N = 305, M = 205;
const int mod = 1e9+7;
const ll inf = 1e18;
const ld Pi = acos(-1);
ll n, m, k, ans;
ll dp[N][M][M], a[N];
int rec(ll pos, ll a1, ll a2){
if(pos >= n) return min(a1, a2) * 5 + (max(a1, a2) - min(a1, a2))*3;
ll &res = dp[pos][a1][a2];
if(res != -1)return res;
res = inf;
ll mn = min(a1, min(a2, a[pos]));
if(mn == a1) res = min(res, rec(pos+1, a2-a1, a[pos]-a1) + mn*7ll);
if(a1 && a2) res = min(res, rec(pos, a1-1, a2-1)+5ll);
if(a1) res = min(res, rec(pos, a1-1, a2)+3ll);
return res;
}
void solve(){
fastios
cin>>n;
for(int i=0;i<n;i++) cin>>a[i];
memset(dp, -1, sizeof(dp));
ans = rec(2ll, a[0], a[1]);
cout<<ans<<"\n";
return;
}
int main(){
fastios
int t = 1;
if(t) solve();
else {
cin>>t;
while (t--) solve();
}
return 0;
}
