HDOJ 2438 三分查找

 

		double min = 0, max = Pi/2,mid, midmid;
		while(max-min > ex)
		{
			mid = (min + max) / 2;
			midmid = (mid + max) / 2;
			if(calc(mid)>=calc(midmid))
				max=midmid;
			else
				min=mid;
		}
		if(calc(min) <= y)
			cout<<"yes"<<endl;
		else cout<<"no"<<endl;