The Race: PC/UVa IDs: 110103/10137

race.java

	
/*
 * Main.java
 *  java program model for www.programming-challenges.com
 */

import java.io.*;
import java.util.*;

class Main implements Runnable{

    public static void main(String args[])  // entry point from OS
    {
    	Main myWork = new Main();  // Construct the bootloader
        myWork.run();            // execute
    }

    public void run() {
        new Q103().run();
    }
}
class Q103 implements Runnable{
	
	public int min_amount_exchange(int num_students, int amount_spent[])
	{
		int total_amount = 0;
		int average_amount = 0;
		
		for(int i=0;i<num_students;i++)
		{
			total_amount += amount_spent[i];
		}
		
		average_amount = total_amount / num_students;
		
		int amount_to_be_given = 0;
		int amount_to_be_received = 0;
		
		for(int i=0;i<num_students;i++)
		{
			if (amount_spent[i] < average_amount )
			{
				amount_to_be_given += (average_amount - amount_spent[i]);
			}
			else if (amount_spent[i] > average_amount )
			{
				amount_to_be_received += (amount_spent[i] - average_amount -1);
			}
		}

		if (amount_to_be_given > amount_to_be_received)
			return amount_to_be_given;
		else 
			return amount_to_be_received;
	}
	
    public void run(){
		try 
		{
			int num = 1;
			BufferedReader is = new BufferedReader(new InputStreamReader(System.in));
			String inputLine;
			while ((inputLine = is.readLine( )) != null) {
				
				int num_students = Integer.parseInt(inputLine.trim());
				if (num_students == 0)
					break;
				
				int amount_spent[] = new int[num_students];
				int exchange_amount = 0;
				for(int i=0 ; i<num_students; i++)
				{
					inputLine = is.readLine( );
					String a[] = inputLine.split("\\.");
					int b = Integer.parseInt(a[0])*100;
					int c = Integer.parseInt(a[1]);
					amount_spent[i] = b+c;
				}
				exchange_amount = min_amount_exchange(num_students, amount_spent);
				System.out.printf("$%d.%02d\n",exchange_amount/100,exchange_amount%100);				
			}
			is.close( );
		} catch (Exception e) {
			System.out.println(e);
		}
    }
    
}