PAT A 1008
/* unknown words :
denote: 表示
specified: 特定的
fulfill: 完成，履行，满足
*/
/*
按题意做就好了，暴力模拟
*/
#include<cstdio>
using namespace std;
int main()
{
int n,pre = 0,now = 0;
scanf("%d",&n);
int sum = n*5;
while(n--)
{
scanf("%d",&now);
if(now>pre) sum += 6*(now-pre);
else sum += 4*(pre-now);
pre = now;
}
printf("%d\n",sum);
return 0;
}
