#include<bits/stdc++.h>
using namespace std;
#include<atcoder/all>
using namespace atcoder;
using ll = long long;
int n;
using P = pair<ll,ll>;
vector<P> p;

bool isconnect(ll x){
	dsu UF(n);
	for(int i = 0;i<n;i++){
		for(int j = i+1;j<n;j++){
			ll dx = p[i].first - p[j].first;
			ll dy = p[i].second - p[j].second;
			if(dx*dx+dy*dy<=x*x){
				UF.merge(i,j);
			}
		}
	}
	if(UF.same(0,n-1))return true;
	return false;
}
void solve(){
	ll l = 0 , r = 200000000;
	while(r-l>1){
		ll m = (l+r)/2;
		if(isconnect(m*10))r = m;
		else l = m;
	}
	cout<<r*10<<endl;
}

signed main(){
	cin.tie(nullptr);
	ios::sync_with_stdio(false);
	cin >> n;
	p = vector<P>(n);
	for(auto &[l,r]:p)cin >> l >> r;
	solve();
}