杭电ACM 1008

Elevator

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 61524    Accepted Submission(s): 33782

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 2
3 2 3 1
0
   
   
   
   

 

Sample Output

   
   
   
   

    
    
    
    17

    
    
    
    
41
    
    
    
    

    
    
    
    
#include<cstdio>
//using namespace std;

int main(){
	const int delay=5,up=6,down=4;
	int past=0,now,num;	
	int time=0;
	

	while(scanf("%d",&num) && 0!=num){
		for(int i=0;i<num;i++){
		    scanf("%d",&now);
			if(now>past){
			   time += (now-past)*up+delay;
			   past=now;
			}else{
				//注意的是可能在同一楼进行操作
			    time += (past-now)*down+delay;
				past=now;
			}
		}
		printf("%d\n",time);
		now=0;
		past=0;
		time=0;
	}
	return 0;
}
/*
测试数据
1 2
3 2 3 1
0
*/