acm 1008 Elevator

#include<stdio.h>int main(){    int n,t,flag,m;    while(scanf("%d",&n)!=EOF&&n!=0){        t=0;        flag=0;        while(n--){            scanf("%d",&m);            if(m>flag)                t+=(m-flag)*6+5;            else                 t+=(flag-m)*4+5;            flag=m;        }        printf("%d\n",t);    }    return 0;}