patA1008 Elevator

#include <iostream>

#include <cstdio>
#include <cmath>
using namespace std;
const int maxn=110;
int num[maxn];
int main(int argc, char** argv) {
int N;
scanf("%d",&N);
num[0]=0;
for(int i=1;i<=N;i++) scanf("%d",&num[i]);
int ans=0;
for(int i=0;i<N;i++){
if(num[i+1]-num[i]>=0){
ans+=(num[i+1]-num[i])*6+5;
}else{
ans+=(abs(num[i+1]-num[i]))*4+5;
} 
} 
printf("%d",ans);
return 0;
}