Hackerrank - find-point solution

Solution to HackerRank FindPoint

Domain Knowledge Required

What is a symmetric point?

Given 2 points P and Q, a symmetric point of P against Q is such that Q is the midpoint of the line joining P and the symmetric point P’. In other words, let’s say a point P’ is the symmetric point. Then,

P-Q-P’are on one line
Dist(PQ) = Dist(QP’)

Code

import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

   public static void main(String[] args) {
       Scanner scn = new Scanner(System.in);
       int testCases = scn.nextInt();
       for (int i = 0; i < testCases; i++) {
           int x1 = scn.nextInt();
           int y1 = scn.nextInt();
           int x2 = scn.nextInt();
           int y2 = scn.nextInt();

           int x3 = 2 * x2 - x1;
           int y3 = 2 * y2 - y1;

           System.out.println(x3 + " " + y3);
       }
   }
}