View Code of Problem 67

import java.util.Scanner;
public class Main {
	public static void main(String[] args) {	
		float x1,x2,x3,x4,y1,y2,y3,y4,k1,k2;
		Scanner scan = new Scanner(System.in);
		while(scan.hasNext()) {
			x1 = scan.nextFloat();
			y1 = scan.nextFloat();
			x2 = scan.nextFloat();
			y2 = scan.nextFloat();
			
			x3 = scan.nextFloat();
			y3= scan.nextFloat();
			x4 = scan.nextFloat();
			y4 = scan.nextFloat();
			
			if(x1!=x2 && x3!= x4) {
				k1 = (y2-y1)/(x2-x1);
				k2 =(y4-y3)/(x4-x3);
				
				if(k1!=k2) {
					System.out.println("Yes");
				} else if(y1-k1*x1!=y3-k2*x3){
                    System.out.println("No");
                }
				else {
					System.out.println("Yes");
				}
			}else if(x1==x2&&x3==x4&&x1!=x3) {
				System.out.println("No");
			}else {
				System.out.println("Yes");
			}
		}
		scan.close();
		}
}