// #include <bits/stdc++.h>
#include <iostream>
#include <cmath>
#include <algorithm>
#include <map>
#include <unordered_map>
#include <vector>
#include <iomanip>
#include <string>
#include <queue>
#include <set>
#include <deque>
using namespace std;
#define int long long
#define endl "\n"
#define fi first
#define se second
const int M=998244353;
const int inf = 1e14;
const int LOG=17;
const int N=300+5;
const int O=200+5;
int n , m , c , w , k , t=1 , q=1 , x , y , z , l , r;
int dp[N][O];
void solve(){
cin >> n;
vector<int>a(n);
for (int i=0;i<n;i++){
cin >> a[i];
}
for (int i=0;i<N;i++){
for (int j=0;j<O;j++){
dp[i][j]=inf;
}
}
dp[0][0]=0;
for (int j=1;j<=a[0];j++){
dp[0][j]=3*j;
}
for (int j=0;j<=a[1];j++){
if (j==0)dp[1][j]=dp[0][a[0]];
int u=min(a[0],j);
dp[1][j]=5*u+3*(max(a[0],j)-u);
}
for (int i=2;i<n;i++){
for (int j=0;j<=a[i];j++){
if (j==0)dp[i][j]=dp[i-1][a[i-1]];
dp[i][j]=dp[i][j-1]+3;
dp[i][j]=min(dp[i][j],dp[i-1][a[i-1]]+3*j);
int u=min({a[i],a[i-1],a[i-2]});
for (int l=0;l<=u;l++){
int u1=min(a[i],a[i-1])-l;
dp[i][j]=min(dp[i][j],7*l+5*u1+3*(max(a[i],a[i-1])-l-u1)+dp[i-2][a[i-2]-l]);
}
}
}
cout << dp[n-1][a[n-1]] << endl;
}
signed main()
{
// #ifndef ONLINE_JUDGE
// freopen("input.txt","r" ,stdin);
// freopen("output.txt","w",stdout);
// #endif
ios::sync_with_stdio(0);//DO NOT USE IN INTERACTIVE
cin.tie(0), cout.tie(0);//DO NOT USE IN INTERACTIVE
cout << fixed << setprecision(4);
srand(time(0));
// int t=1;
// cin >> t;
for (int _=1;_<=t;_++){
solve();
q++;
}
}
