AOJ0021

gistfile1.java

import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scn = new Scanner(System.in);
		int n = scn.nextInt();
		for (int i = 0; i < n; i++) {
			double x1 = scn.nextDouble();
			double y1 = scn.nextDouble();
			double x2 = scn.nextDouble();
			double y2 = scn.nextDouble();
			double x3 = scn.nextDouble();
			double y3 = scn.nextDouble();
			double x4 = scn.nextDouble();
			double y4 = scn.nextDouble();
			if (x2 - x1 == 0 || x4 - x3 == 0) {
				if (x2 - x1 == 0 && x4 - x3 == 0) {
					System.out.println("YES");
				} else {
					System.out.println("NO");
				}
			} else {
				double a1 = (y2 - y1) / (x2 - x1);
				double a2 = (y4 - y3) / (x4 - x3);
				if (a1 == a2) {
					System.out.println("YES");
				} else {
					System.out.println("NO");
				}
			}
		}
	}
}