南阳 无线网覆盖

 

http://acm.nyist.net/JudgeOnline/problem.php?pid=199

 

#include<stdio.h>
#include<math.h>
int main()
{
	int t;
	double l,w,r;
	scanf("%d",&t);
	while(t--)
	{
		scanf("%lf%lf%lf",&l,&w,&r);
		if(w>=2*r)printf("impossible\n");
		else
		{
			double d=sqrt(4*r*r-w*w);
			//printf("%lf\n",d);
			if(d<1.0)printf("impossible\n");
			
			{
				double temp=l/d;
				//判断temp是不是小数 
				if(temp==(int)(temp))printf("%d\n",(int)(temp));
				if(temp>(int)temp) printf("%d\n",(int)(temp) + 1);
			}
		}
	}
	return 0;
}