1008 Elevator (20)（20 分）
The highest building in our city has only one elevator. A request list
is made up with N positive numbers. The numbers denote at which floors
the elevator will stop, in specified order. It costs 6 seconds to move
the elevator up one floor, and 4 seconds to move down one floor. The
elevator will stay for 5 seconds at each stop.
For a given request list, you are to compute the total time spent to
fulfill the requests on the list. The elevator is on the 0th floor at
the beginning and does not have to return to the ground floor when the
requests are fulfilled.
Input Specification:
Each input file contains one test case. Each case contains a positive
integer N, followed by N positive numbers. All the numbers in the input
are less than 100.
Output Specification:
For each test case, print the total time on a single line.
Sample Input:
3 2 3 1
Sample Output:
41
