一道嚇人的水題 HDU 1140

題目意思很嚇人。經過分析之後就變成了一道比大小的題目... 囧~

#include<set>
#include<iostream>
using namespace std;

class Point3D{
public:
 	  double x,y,z;
 	  Point3D( double a=0,double b=0,double c=0 ){
	   		   x=a; y=b; z=c;
	  }
}A[111],B[111];

double dis( Point3D a,Point3D b )
{
 	   return (a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y)+(a.z-b.z)*(a.z-b.z);
}

int main()
{
 	int N,M;
 	Point3D O(0,0,0);
 	while( scanf("%d %d",&N,&M)!=EOF )
 	{
	 	   if( N==0&&M==0 )
	 	   	   break;
	 	   for( int i=0;i<N;i++ )
	 	   		scanf( "%lf %lf %lf",&A[i].x,&A[i].y,&A[i].z );
	 	   for( int i=0;i<M;i++ )
	 	   		scanf( "%lf %lf %lf",&B[i].x,&B[i].y,&B[i].z );
	 	   int ans=0;
	 	   for( int j=0;j<M;j++ )
	 	   for( int i=0;i<N;i++ )
	 	   {
		   		if( dis(A[i],O)>dis(A[i],B[j])+dis(B[j],O) )
		   		{
		   			ans++;
		   			break;
		 		}
		   }
		   printf( "%d\n",ans );
  	}
  	return 0;
}