#include<fstream>
#include<memory.h>
using namespace std;
int map[1010][1010],mapa[1010][1010];
int a[1010];
int boyh[501],boya[510],girlh[510],girla[510];
int d[1010]={-1};
int n,m,i,j,k,l,r,mid;
bool v[510];
bool find(int k)
{
	int i;
	int al=1;
	int br=n;
	if (k<=br)
	{
		al=al+n;
		br=br+n;
	}
	for (i=al;i<=br;i++)
	{
		if ((map[k][i]>0)and(map[k][i]<=a[mid])) 
			if (d[i]==-1)
		{
			d[k]=i;
			d[i]=k;
			map[i][k]=map[k][i];
			map[k][i]=0;
			return true;
		}else{
			if (v[i]==true)
			{v[i]=false;
				if (find(i))
				{
					v[i]=false;
					d[k]=i;
					map[i][k]=map[k][i];
					map[k][i]=0;
				    return true;
				}
			}
		}
	}
	return false;
}
bool tg(int x)
{
	int sum=0;
	for (i=1;i<=n+n;i++)
		d[i]=-1;
	for (int i=1;i<=n;i++)
	{
		if (d[i]==-1)
		{
			if (find(i))
				sum++;
			memset(v,true,sizeof(v));
		}
	}
	for (int ii=1;ii<=n+n;ii++)
		for(int jj=1;jj<=n+n;jj++)
			map[ii][jj]=mapa[ii][jj];
		sum=0;
	for (int ii=1;ii<=n;ii++)
		if (d[ii]!=-1) sum++;
	if (sum==n)
	{
		return true;
	}else{
		return false;
	}
}
int main()
{
	ifstream fin("christmas.in");
	ofstream fout("christmas.out");
	fin>>n;
	for (i=1;i<=n;i++)
		fin>>boyh[i]>>boya[i];
	for (i=1;i<=n;i++)
		fin>>girlh[i]>>girla[i];
	m=2*n;
	int p=0;
	for (i=1;i<=n;i++)
		for (j=1;j<=n;j++)
		{
			map[i][j+n]=(boyh[i]-girlh[j])*(boyh[i]-girlh[j])+(boya[i]-girla[j])*(boya[i]-girla[j]);
			p++;
			a[p]=map[i][j+n];
		}
	for (i=1;i<=m;i++)
		for (j=1;j<=m;j++)
			mapa[i][j]=map[i][j];
	l=1;r=p;
	mid=(l+r) / 2;
	while (l<r)
	{
		if (tg(a[mid]))
		{
			r=mid;
			mid=(l+r) / 2;
		}
		else
		{
			l=mid+1;
			mid=(l+r) / 2;
		}
	}
	fout<<a[l];
	fin.close();
	fout.close();
	return 0;
}