平面上最接近的点对(分治)

#include<stdio.h>
#include<math.h>

struct point{
	double x,y;
}p[60005];

int main()
{
	int n,i,j;
	double length,temp=10000.0000;
	scanf("%d",&n);
	for(i=0;i<n;i++)
	{
		scanf("%lf%lf",&p[i].x,&p[i].y);
	}
	
	for(i=0;i<n;i++)
	{
		for(j=i+1;j<n;j++)
		{
			length = sqrt(fabs(((p[i].x-p[j].x)*(p[i].x-p[j].x)+(p[i].y-p[j].y)*(p[i].y-p[j].y))));
			if(length<temp) temp=length;
		}
	} 
	printf("%.4lf",temp);
	return 0;
}