#include <bits/stdc++.h>
#include"factories.h"
using namespace std;
typedef long long ll;
#pragma GCC optimize ("Ofast")
const int maxn = 5e5 + 10, maxlog = 19;
int pai[maxn], h[maxn], block[maxn], sz[maxn];
ll ans[maxn];
ll dist[maxn][maxlog];
vector<pair<int, int>> G[maxn];
vector<int> tree[maxn], lista;
void dfs(int x, int p)
{
pai[x] = p;
sz[x] = 1;
lista.push_back(x);
for(auto u : G[x])
{
int v = u.first;
if(block[v] or v == p) continue;
dfs(v, x);
sz[x] += sz[v];
}
}
void find_dist(int v, int p, ll depht)
{
dist[v][h[v]++] = depht;
for(auto u : G[v])
{
if(u.first == p or block[u.first]) continue;
find_dist(u.first, v, depht + u.second);
}
}
int find_centroid(int x)
{
lista.clear();
dfs(x, x);
int centro = x;
int qt = sz[x];
for(auto u : lista)
{
bool ok = true;
if(qt - sz[u] > qt/2) ok = false;
for(auto v : G[u])
{
int at = v.first;
if(block[at] or pai[u] == at) continue;
if(sz[at] > qt/2) ok = false;
}
if(ok) centro = u;
}
find_dist(centro, -1, 0);
return centro;
}
int build(int x)
{
x = find_centroid(x);
block[x] = true;
for(auto u : G[x])
{
int at = u.first;
if(block[at]) continue;
int v = build(at);
tree[x].push_back(v);
tree[v].push_back(x);
}
return x;
}
void init(int x, int p)
{
pai[x] = p;
for(auto u : tree[x])
{
if(u == p) continue;
init(u, x);
}
}
void Init(int N, int A[], int B[], int D[])
{
for(int i = 0; i < N - 1; i++)
{
G[A[i]].push_back({B[i], D[i]});
G[B[i]].push_back({A[i], D[i]});
}
int ct = build(1);
init(ct, -1);
for(int i = 0; i < maxn; i++) ans[i] = (long long)1e17;
}
long long Query(int S, int X[], int T, int Y[])
{
for(int i = 0; i < S; i++)
{
int v = X[i];
int x = v;
for(int j = h[x] - 1; j >= 0; j--)
{
ans[v] = min(ans[v], dist[x][j]);
v = pai[v];
}
}
ll resp = 1e16;
for(int i = 0; i < T; i++)
{
int v = Y[i];
int x = v;
for(int j = h[x] - 1; j >= 0; j--)
{
resp = min(resp, ans[v] + dist[x][j]);
v = pai[v];
}
}
for(int i = 0; i < S; i++)
{
int v = X[i];
int x = v;
for(int j = h[x] - 1; j >= 0; j--)
{
ans[x] = 1e16;
x = pai[x];
}
}
return resp;
}
