delete pics to save space

2.1473.cpp

@@ -0,0 +1,57 @@
+#include<cstdio>
+#include<cstring>
+#include<cstdlib>
+#include<cmath>
+#include<algorithm>
+const double EPS=1e-9;
+using namespace std;
+const int MAXN=10010;
+const double PI=acos(-1.0);
+struct point
+{ double x,y; };
+int N;
+point P[MAXN];
+int dcmp(double a)
+{
+	return fabs(a)<EPS?0:(a<0?-1:1);
+}
+double GetH(double R)
+{
+	double maxH=0.0;
+	for(int i=0;i<N;++i)
+	{
+		double tmp=R*P[i].y/(R-P[i].x);
+		if(dcmp(tmp-maxH)>0) maxH=tmp;
+	}
+	return maxH;
+}
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	while(scanf("%d",&N)==1)
+	{
+		double maxR=0.0;
+		for(int i=0;i<N;i++)
+		{
+			double x,y,z;
+			scanf("%lf%lf%lf",&x,&y,&z);
+			P[i].x=sqrt(x*x+y*y);
+			P[i].y=z;
+			maxR=max(maxR,P[i].x);
+		}
+		double low=maxR,high=1e10;
+		while(dcmp(high-low)>0)
+		{
+			double mid=(low+high)/2.0;
+			double midmid=(mid+high)/2.0;
+			double midV=GetH(mid)*mid*mid;
+			double midmidV=GetH(midmid)*midmid*midmid;
+			if(dcmp(midV-midmidV)<=0) high=midmid;
+			else low=mid;
+		}
+		printf("%.3f %.3f\n",GetH(low),low);
+	}
+	return 0;
+}