#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cstring>

using namespace std;

const int oo=2000000000;

int n,ans;
int x[51],y[51];
int d[51];
bool yy[51];

int dis(int i,int j)
{
	if (x[i]==x[j] && y[i]==y[j]) return 1;
	return (abs(x[i]-x[j])+abs(y[i]-y[j])+1)/2;
}

int main()
{
	freopen("ppg.in","r",stdin);
	freopen("ppg.out","w",stdout);
	scanf("%d",&n);
	for (int i=1;i<=n;i++)
	{
		scanf("%d%d",x+i,y+i);
	}
	
	for (int i=1;i<=n;i++) d[i]=oo;d[1]=0;
	
	int now=1;int maxd;
	for (int ti=1;ti<n;ti++)
	{
		yy[now]=true;
		maxd=oo;
		for (int i=1;i<=n;i++)
		if (!yy[i] && d[i]>=dis(i,now)) d[i]=dis(i,now);
		for (int i=1;i<=n;i++)
		if (!yy[i] && d[i]<=maxd) maxd=d[i],now=i;
		ans=max(ans,d[now]);
	}
	
	printf("%d\n",ans);
	return 0;
}