#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <bitset>
#include <cstdio>
#include <limits>
#include <vector>
#include <cstdlib>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <functional>
#include <iomanip>
#include <unordered_map>
#include <memory.h>
#include <unordered_set>
#include <fstream>
#include <random>
using namespace std;
int h[301];
int dp[305][205][205];
int main(void)
{
cin.tie(0);
ios::sync_with_stdio(false);
int n;
cin >> n;
for (int i = 0; i < n; i++)
{
cin >> h[i];
}
if (n == 1)
{
cout << 3 * h[0] << '\n';
return 0;
}
else if (n == 2)
{
int x = min(h[0], h[1]);
cout << 5 * x + (h[0] - x) * 3 + (h[1] - x) * 3 << '\n';
return 0;
}
for (int i = 0; i <= 300; i++)
{
for (int j = 0; j <= 200; j++)
{
for (int k = 0; k <= 200; k++)
{
dp[i][j][k] = 1e9;
}
}
}
dp[0][0][0] = 0;
for (int i = 0; i < n + 2; i++)
{
for (int j = 200; j>=0; j--)
{
for (int k = 200;k>=0;k--)
{
if (dp[i][j][k] >= 1e9)
{
continue;
}
if (k - 1 >= 0)
{
dp[i][j][k-1] = min(dp[i][j][k-1], dp[i][j][k] + 3);
}
if (j - 1 >= 0 && k - 1 >= 0)
{
dp[i][j - 1][k - 1] = min(dp[i][j - 1][k - 1], dp[i][j][k] + 5);
}
if (h[i] >= j && k >= j)
{
dp[i + 1][k - j][h[i] - j] = min(dp[i + 1][k - j][h[i] - j], dp[i][j][k] + 7 * j);
}
}
}
}
cout << dp[n+2][0][0] << '\n';
return 0;
}
