#include "towns.h"
#include<bits/stdc++.h>
using namespace std;
const int inf = 2e8 + 10;
int n, d[110][110];
int Dis(int v, int u){
if (v == u or d[v][u] > 0)
return d[v][u];
return d[v][u] = d[u][v] = getDistance(v,u);
}
int getDis(int v, int u, int w){
return (Dis(v,u)+Dis(v,w)-Dis(u,w))/2;
}
int hubDistance(int N, int sub){
memset(d, 0, sizeof d);
n = N;
int Q1 = 0, Q2 = 0;
for (int i = 1; i < n; i++)
if (Dis(0,i) > Dis(0,Q1))
Q1 = i;
for (int i = 1; i < n; i++)
if (Dis(Q1,i) > Dis(Q1,Q2))
Q2 = i;
int R = inf;
vector<int> a;
for (int v = 0; v < n; v++){
if (v == Q1 or v == Q2)
continue;
int A = getDis(Q1, Q2, v), B = getDis(Q2, Q1, v);
a.push_back(A);
R = min(R,max(A,B));
}
if (sub <= 2)
return R;
sort(a.begin(), a.end());
a.resize(unique(a.begin(),a.end())-a.begin());
int m = 1;
for (auto it : a){
int now = 0;
for (int v = 0; v < n; v++){
if (v == Q1 or v == Q2)
continue;
if (getDis(Q1, Q2, v) == it)
now ++;
}
int t = max(it,Dis(Q1,Q2)-it);
if (t == R and now <= n/2 and m <= n/2 and (n-now-m) <= n/2)
return R;
m += now;
}
return -R;
}
