#include <iostream> using namespace std; int main() { int n; int a[200]; while (cin >> n&&n) { int i,sum=0,t,s; for (i = 1; i <= n; i++) cin >> a[i]; a[0] = 0; for (i = 1; i <= n; i++) { if (a[i]>a[i - 1]) { t = a[i] - a[i - 1]; s = t*6 +5; sum = sum + s; } else { t = a[i - 1] - a[i]; s = t * 4 + 5; sum = sum + s; } } cout << sum << endl;
} }