HDOJ 1008 Elevator

Elevator

Problem Description

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

There are multiple test cases. Each case contains a positive integer N, followed by N positive numbers. All the numbers in the input are less than 100. A test case with N = 0 denotes the end of input. This test case is not to be processed.

 

Output

Print the total time on a single line for each test case.

 

Sample Input

1 23 2 3 10

 

Sample Output

1741

 

这个题有个坑，就是必须按照它给的顺序下电梯，比如2,3,1.  得先到2层，再到3层，再到1层

还有一个坑就是同层到同层，如2到2，也得停留5秒，以下是代码：

#include<stdio.h>
int main()
{
    int n,i,a[105];
    while(scanf("%d",&n)&n!=0)
    {
      for(i=1;i<=n;i++)
        scanf("%d",&a[i]);
      int sum=0;
      a[0]=0;
      for(i=1;i<=n;i++)
      {
          if(a[i]>a[i-1])  sum+=6*(a[i]-a[i-1])+5;
          if(a[i]==a[i-1])  sum+=5;        //此处是同层的情况，注意了~~
          if(a[i]<a[i-1])   sum+=4*(a[i-1]-a[i])+5;
      }
      printf("%d\n",sum);
    }
    return 0;
}