#include <bits/stdc++.h>
using namespace std;
const int INF = 10000000;
int main(){
int N;
cin >> N;
vector<int> h(N);
for (int i = 0; i < N; i++){
cin >> h[i];
}
vector<vector<vector<int>>> dp(N + 1, vector<vector<int>>(201, vector<int>(201, INF)));
dp[0][0][0] = 0;
for (int i = 0; i < N; i++){
for (int j = 0; j <= h[i]; j++){
for (int k = j; k <= 200; k++){
dp[i + 1][k - j][h[i] - j] = min(dp[i + 1][k - j][h[i] - j], dp[i][j][k] + j * 7);
}
}
for (int j = 200; j >= 0; j--){
for (int k = 199; k >= 0; k--){
if (j < 200){
dp[i + 1][j][k] = min(dp[i + 1][j][k], dp[i + 1][j + 1][k + 1] + 5);
}
dp[i + 1][j][k] = min(dp[i + 1][j][k], dp[i + 1][j][k + 1] + 3);
}
}
}
cout << dp[N][0][0] << endl;
}
