#include "towns.h"
#include <bits/stdc++.h>
using namespace std;
const int INF = 1e9;
int n;
vector<int> calc_dist(int src)
{
vector<int> dist(n);
for(int i=0;i<n;i++)
dist[i] = getDistance(src,i);
return dist;
}
int hubDistance(int N, int sub)
{
//int _ = getDistance(0,1);
n = N;
vector<int> dist0 = calc_dist(0);
int cap1=0;
for(int i=0;i<n;i++)
if(dist0[i]>dist0[cap1])
cap1=i;
vector<int> dist1 = calc_dist(cap1);
int cap2=0;
for(int i=0;i<n;i++)
if(dist1[i]>dist1[cap2])
cap2=i;
vector<int> dist2 = calc_dist(cap2);
int mnm = dist1[cap2];
for(int i=0;i<n;i++)
{
int injos = dist1[i] + dist2[i] - dist1[cap2];
assert(injos%2==0);
injos/=2;
mnm = min(mnm, max(dist1[i], dist2[i]) - injos);
}
return mnm;
}
