View Code of Problem 67

#include<stdio.h>
#include<math.h>
#include<string.h>
 void main(){
	float x1,x2,x3,x4,y1,y2,y3,y4;
	while(scanf("%f%f%f%f%f%f%f%f",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4)!=EOF)
	{
		if(x2!=x1||x3!=x4){
		if((y2-y1)/(x2-x1)==(y4-y3)/(x4-x3))
			printf("No");
		else 
			printf("Yes");
		}
		else if(x1==x2||x3==x4)
		{
			if((y4-y3)*(x2-x1)==(y2-y1)*(x4-x3))
				printf("No");
			else
				printf("Yes");
		}
		printf("\n");
	}
}