hdu1008 Elevator

Elevator

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 39688    Accepted Submission(s): 21712

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
   
   
   
   

刚开始做是WA,忽略了有相等的情况

import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.FileReader;
import java.io.StreamTokenizer;
import java.io.PrintWriter;
import java.io.InputStream;
import java.io.FileInputStream;
import java.io.OutputStreamWriter;
import java.util.Scanner;

class Main
{
	public static final boolean DEBUG = false;
	StreamTokenizer tokenizer;
	public int n;
	public int[] request;
	
	public void init() throws IOException
	{
		BufferedReader reader;
		if (DEBUG) {
			reader = new BufferedReader(new FileReader("d:\\OJ\\uva_in.txt"));
		} else {
			reader = new BufferedReader(new InputStreamReader(System.in));
		}
		
		tokenizer = new StreamTokenizer(reader);
	}
	
	public  boolean input() throws IOException
	{
		tokenizer.nextToken();
		if (tokenizer.ttype == StreamTokenizer.TT_NUMBER) {
			n = (int)tokenizer.nval;
		}
		
		
		if (n == 0) return false;
		
		request = new int[n + 1];
		request[0] = 0;
		for (int i = 1; i <= n; i++) {
			tokenizer.nextToken();
			if (tokenizer.ttype == StreamTokenizer.TT_NUMBER) {
				request[i] = (int)tokenizer.nval;
			} else if (tokenizer.ttype == StreamTokenizer.TT_EOL);
		}
		return true;
	}
	
	public int solve()
	{
		int ans = 0;
		for (int i = 1; i <= n; i++) {
			if (request[i] > request[i - 1]) {
				ans += (request[i] - request[i -1]) * 6 + 5;
			} else {
				ans += (request[i - 1] - request[i]) * 4 + 5;
			}
		}
		
		return ans;
	}
	
	public static void main(String[] args) throws IOException
	{
		Main solver = new Main();
		solver.init();
		
		while (solver.input()) {
			int ans = solver.solve();
			System.out.println(ans);
		}
	}
}