View Code of Problem 67

#include <stdio.h>
#include <stdlib.h>
#include<ctype.h>
#include<string.h>
#include<math.h>
#include<stdbool.h>
int main()
{
	int x1, x2, x3, x4, y1, y2, y3, y4;
	float b1,b2;
	float k1, k2;
	while (scanf("%d%d", &x1, &y1)!=EOF)
	{
		scanf("%d%d%d%d%d%d", &x2, &y2, &x3, &y3, &x4, &y4);
		if (x1 == x2 && x3 == x4 && x1 != x3)
		{
			printf("No\n");
		}
		else if (x1 == x2 && x3 == x4 && x1 == x3)
			printf("Yes\n");
		else
		{
			k1 = 1.0*(y2 - y1) / (x2 - x1);
			k2 = 1.0*(y4 - y3) / (x4 - x3);
			
			if (k1 == k2)
			{
		
				b1 = y1 - k1 * x1;
				b2 = y3 - k2 * x3;
				if (b1 == b2)
					printf("Yes\n");
				else printf("No\n");
			}else printf("Yes\n");
		}
	}
	return 0;
}