#include "towns.h"
#include <bits/stdc++.h>
using namespace std;
int inf = 1e9;
int dA[115], dB[115], n;
int l[115], dep[115];
bool eq(int i, int j)
{
if (getDistance(i, j) == dep[i] + dep[j])
return false;
return true;
}
bool check(vector<int> v)
{
if ((int)v.size() <= n / 2)
return true;
vector<int> coef(n);
vector<pair<int, int>> cr;
for (auto i : v)
coef[i] = 1;
for (auto i : v)
{
if (cr.empty())
cr.push_back({i, 1});
else
{
int x = cr.back().first, y = cr.back().second;
cr.pop_back();
if (eq(x, i))
{
y++;
coef[x]++;
coef[i] = 0;
cr.push_back({x, y});
}
else
{
y--;
if (y != 0)
cr.push_back({x, y});
}
}
}
///gg de ce e vector xd
if (cr.empty())
return true;
int x = cr[0].first;
int fre = 0;
for (auto i : v)
{
if (coef[i] != 0)
{
if (eq(i, x))
fre += coef[i];
}
}
if (fre <= n / 2)
return true;
return false;
}
int hubDistance(int N, int sub)
{
int A = 0, B = 0, C = 0, diam;
n = N;
dA[0] = 0;
for (int i = 1; i < n; i++)
{
dA[i] = getDistance(0, i);
if (dA[i] > dA[B])
B = i;
}
for (int i = 0; i < n; i++)
{
if (i == 0)
dB[i] = dA[B];
else if (i == B)
dB[i] = 0;
else
dB[i] = getDistance(B, i);
if (dB[i] > dB[C])
C = i;
}
diam = dB[C];
for (int i = 0; i < n; i++)
l[i] = dep[i] = 0;
dep[A] = (dA[C] + dA[B] - diam) / 2;
l[A] = dA[B] - dep[A];
vector<int> L, M, R;
set<int> ls;
ls.insert(l[A]);
map<int, int> oo;
map<int, vector<int>> vv;
for (int i = 0; i < n; i++)
{
int df = dB[i] - dA[i];
if (df > l[A] - dep[A])
M.push_back(i), oo[l[A]]++;
else if (df == l[A] - dep[A])
L.push_back(i), oo[inf]++;
else
{
int delt = (l[A] - dep[A] - df) / 2;
R.push_back(i);
l[i] = l[A] - delt;
ls.insert(l[i]);
oo[l[i]]++;
vv[l[i]].push_back(i);
dep[i] = dB[i] - l[i];
}
}
int difmin = 1e9;
for (auto it : ls)
difmin = min(difmin, max(it, diam - it));
vector<int> cand;
for (auto it : ls)
if (max(it, diam - it) == difmin)
cand.push_back(it);
int RR = difmin;
if (sub <= 2)
return RR;
bool found = false;
for (auto it : cand)
{
if (it != A)
{
int st = 0, eu = 0, dr = 0;
for (auto itt : oo)
{
if (itt.first < it)
dr += itt.second;
else if (itt.first == it)
eu += itt.second;
else
st += itt.second;
}
if (st > n / 2 or dr > n / 2)
continue;
if (eu <= n / 2)
{
found = true;
break;
}
found |= check(vv[it]);
}
else
{
int dr = 0;
for (auto itt : oo)
if (itt.first < it)
dr += itt.second;
if (dr > n / 2)
continue;
vector<int> vec;
for (auto el : M)
{
vec.push_back(el);
dep[el] = dB[el] - dB[A];
}
for (auto el : L)
{
vec.push_back(el);
dep[el] = dB[el] - dB[A];
}
found |= check(vec);
}
}
if (!found)
RR = -RR;
return RR;
}
///de cand nu a mai trebuit sa gandesc ca sa rezolv o problema...
