2408987_wa.c

北大大牛代码 1240道题的原代码 超级权威

#include <stdio.h>
#include <math.h>
#define zero 1e-2
#define PI 3.141592653
int main()
{
	double l1, l2, l3;
	double a1, a2, a3;
	double x1, x2, x3, y1, y2, y3;

	while(scanf("%lf%lf%lf%lf%lf%lf",&x1,&y1,&x2,&y2,&x3,&y3)==6)
	{
		l1 = sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
		l2 = sqrt((x1-x3)*(x1-x3)+(y1-y3)*(y1-y3));
		l3 = sqrt((x3-x2)*(x3-x2)+(y3-y2)*(y3-y2));
		if(l1+l2-l3<=0||l1+l3-l2<=0||l3+l2-l1<=0)
		{
			printf("Not a Triangle\n");
			continue;
		}
		if((fabs(l1-l2)<=zero)&&(fabs(l3-l2)<=zero))
		{
			printf("Equilateral ");
			goto ang;
		}
		if((fabs(l1-l2)<=zero)||(fabs(l3-l2)<=zero))
		{
			printf("Isosceles ");
			goto ang;
		}
		printf("Scalene ");
		ang:;
		a1 = acos((l2*l2+l3*l3-l1*l1)/(2.0*l2*l3));
		a2 = acos((l1*l1+l3*l3-l2*l2)/(2.0*l1*l3));
		a3 = acos((l2*l2+l1*l1-l3*l3)/(2.0*l2*l1));
		//printf("%lf %lf %lf %lf %lf %lf\n",l1,l2,l3,a1,a2,a3);
		if((a1-PI/2.0)<zero||(a2-PI/2.0)<zero||(a3-PI/2.0)<zero)
		{
			printf("Obtuse\n");
			continue;
		}
		if((fabs(a1-PI/2.0)<zero)||(fabs(a2-PI/2.0)<zero)||(fabs(a3-PI/2.0)<zero))
		{
			printf("Right\n");
			continue;
		}
		printf("Acute\n");
	}
	printf("End of Output\n");
	return 1;
}