// REPUTATION RATING = -100
#include "factories.h"
#include <bits/stdc++.h>
#define int long long
#define ll long long
#define fi first
#define se second
#define pb push_back
#define all(lmao) lmao.begin(), lmao.end()
using namespace std;
typedef pair<int,int> pii;
typedef tuple<int,int,int> tp;
const int N = 5e5 + 5;
const int oo = 1e9;
const int mod = 1e9 + 7;
int n, q, st[N << 1], f[N][22], in[N], en[N], demin, a[N];
ll d[N];
vector<pii> p[N];
void dfs(int u,int v){
in[u] = ++demin;
a[in[u]] = u;
if(u == 1) for(int i = 0; i <= 20; i ++) f[u][i] = u;
else{
f[u][0] = v;
for(int i = 1; i <= 20; i ++) f[u][i] = f[f[u][i - 1]][i - 1];
}
for(auto jj : p[u]){
int j = jj.fi;
int w = jj.se;
if(j == v) continue;
d[j] = d[u] + w;
dfs(j, u);
}
en[u] = demin;
}
bool kt(int u,int v){
return in[u] <= in[v] && in[v] <= en[u];
}
int lca(int u,int v){
if(kt(u, v)) return u;
else{
int kq = u;
for(int i = 20; i >= 0; i --){
if(kt(f[u][i], v)) kq = f[u][i];
else u = f[u][i];
}
return kq;
}
}
void update(int i,int x){
i += n - 1;
st[i] = x;
while(i > 1){
i /= 2;
st[i] = min(st[i << 1], st[i << 1|1]);
}
}
int get(int l,int r){
r++;
int ret = 1e9;
for(l += n - 1, r += n - 1; l < r; l /= 2, r /= 2){
if(l & 1) ret = min(ret, st[l ++]);
if(r & 1) ret = min(ret, st[-- r]);
}
return ret;
}
void Init(int N, int A[], int B[], int D[]){
n = N;
for(int i = 0; i < n - 1; i ++){
int x = A[i] + 1, y = B[i] + 1, w = D[i];
cerr << x << " " << y << " " << w << "g\n";
p[x].pb({y, w});
p[y].pb({x, w});
}
dfs(1, 0);
for(int i = 1; i <= 2 * n; i ++) st[i] = oo;
}
long long Query(int S, int X[], int T, int Y[]){
for(int i = 0; i < S; i ++) X[i]++;
for(int i = 0; i < T; i ++) Y[i]++;
ll ans = (int)1e18, kq = (int)1e18;
for(int i = 0; i < S; i ++)
for(int j = 0; j < T; j ++)
kq = min(kq, d[X[i]] + d[Y[j]] - 1LL * 2 * d[lca(X[i], Y[j])]);
return kq;
cerr << S << " " << T << "\n";
for(int time = 0; time <= 1; time ++){
cerr << time << "r\n";
for(int i = 0; i < S; i ++){
int j = X[i];
cerr << j << " ";
update(in[j], in[j]);
}
cerr << "\n";
for(int i = 0; i < T; i ++){
int j = Y[i];
// cerr << j
int u = get(in[j], en[j]);
if(u == oo) continue;
u = a[u];
ans = min(ans, d[j] + d[u] - 1LL * 2 * d[lca(u, j)]);
}
for(int i = 0; i < S; i ++){
int j = X[i];
update(in[j], oo);
}
if(time == 0){
swap(S, T);
swap(X, Y);
}
}
return ans;
}
//#define LOCAL
int A[N], B[N], C[N], X[N], Y[N], S, T;
#ifdef LOCAL
signed main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define task "v"
if(fopen(task ".inp","r")){
freopen(task ".inp","r",stdin);
freopen(task ".out","w",stdout);
}
cin >> n >> q;
for(int i = 0; i < n - 1; i ++){
cin >> A[i] >> B[i] >> C[i];
}
Init(n, A, B, C);
while(q--){
cin >> S >> T;
for(int i = 0; i < S; i ++) cin >> X[i];
for(int i = 0; i < T; i ++) cin >> Y[i];
cout << Query(S, X, T, Y) << "\n";
}
}
#endif // LOCAL
Compilation message
/usr/bin/ld: /tmp/cczJKqhU.o: in function `main':
grader.cpp:(.text.startup+0x37d): undefined reference to `Init(int, int*, int*, int*)'
/usr/bin/ld: grader.cpp:(.text.startup+0x412): undefined reference to `Query(int, int*, int, int*)'
collect2: error: ld returned 1 exit status
