#include <iostream>
#include <cstdio>
#include <queue>
#include <cstring>
#include <algorithm>
using namespace std;
queue<int>q;
int vis[1010];
struct T{
	int x,y;
}A[1010];
int n;
bool dis(int i,int j,long long x){
	return (A[i].x-A[j].x)*(A[i].x-A[j].x)+(A[i].y-A[j].y)*(A[i].y-A[j].y)<=x;
}
bool judge(int x){
	memset(vis,0,sizeof(vis));
	q.push(1);
	vis[1]=1;
	int cnt=1;
	while(!q.empty()){
		int cd=q.front();
		q.pop();
		for(int j=1;j<=n;j++){
			if(j==cd)
				continue;
			if(dis(j,cd,x)&&!vis[j]){
				q.push(j);
				vis[j]=1;
				cnt++;
			}
		}
	}
	return cnt==n;
}
int main(){
	freopen("moocast.in","r",stdin);
	freopen("moocast.out","w",stdout);
	scanf("%d",&n);
	int xmax=0,ymax=0;
	for(int i=1;i<=n;i++){
		scanf("%d %d",&A[i].x,&A[i].y);
		xmax=max(xmax,A[i].x);
		ymax=max(ymax,A[i].y);
	}
	int r=xmax*xmax+ymax*ymax,l=0;
	while(l+1<r){
		int mid=(l+r)>>1;
		if(judge(mid))
			r=mid;
		else l=mid;
	}
	if(judge(l))
		printf("%d\n",l);
	else printf("%d\n",r);
return 0;
}