UVA 10242 Java

import java.util.*;
import static java.lang.System.*;

public class main{
  public static void main(String[] args) {
    Scanner sc=new Scanner(System.in);
    while(sc.hasNextDouble())
    {
    	double[] px = new double[4];
    	double[] py = new double[4];
    	double x = 0, y = 0;
    	for(int i = 0; i < 4; i++)
    	{
    		px[i] = sc.nextDouble();
    		py[i] = sc.nextDouble();
    		x += px[i];
    		y += py[i];
    	}
    	for(int i = 0; i < 4; i++)
    		for(int j = i + 1; j < 4; j++)
    			if(px[i] == px[j] && py[i] == py[j])
    			{
    				System.out.printf("%.3f %.3f\r\n", x - px[i] * 3, y - py[i] * 3); 
    				i = j = 4;
    			}
    }
  }
};