Elevator

 1 #include <bits/stdc++.h>
 2 #define lid id<<1
 3 #define rid id<<1|1
 4 #define maxn 50005
 5 using namespace std;
 6 int main()
 7 {
 8     int n;
 9     while(~scanf("%d",&n)&&n)
10     {
11         int now=0;
12         int ans=0;
13         for(int i=0;i<n;i++)
14         {
15             int floor;
16             scanf("%d",&floor);
17             if(floor-now>0)
18             {
19                 ans+=(floor-now)*6;
20                 ans+=5;
21                 now=floor;
22             }
23             else
24             {
25                 ans+=(now-floor)*4;
26                 ans+=5;
27                 now=floor;
28             }
29         }
30         printf("%d\n",ans);
31     }
32     return 0;
33 }