#include <bits/stdc++.h>
using namespace std;
vector<long long> d;
vector<int> dep;
vector<vector<pair<int, int>>> g;
vector<vector<int>> up;
int lg;
void dfs(int u) {
for (int i = 1; i < lg; i++) up[i][u] = up[i - 1][up[i - 1][u]];
for (auto [v, w] : g[u])
if (v ^ up[0][u])
d[v] = d[u] + w, dep[v] = dep[u] + 1, up[0][v] = u, dfs(v);
}
int lca(int u, int v) {
if (dep[u] < dep[v]) swap(u, v);
int k = dep[u] - dep[v];
for (int i = 0; i < lg; i++)
if (k >> i & 1)
u = up[i][u];
if (u == v) return u;
for (int i = lg - 1; i >= 0; i--)
if (up[i][u] ^ up[i][v])
u = up[i][u], v = up[i][v];
return up[0][u];
}
long long dist(int u, int v) {
return d[u] + d[v] - (d[lca(u, v)] << 1);
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
int n, q;
cin >> n >> q;
while ((1 << lg) <= n) ++lg;
g.resize(n), d.resize(n), dep.resize(n);
up = vector<vector<int>> (lg, vector<int> (n));
for (int i = 1; i < n; i++) {
int u, v, w;
cin >> u >> v >> w;
g[u].push_back({v, w});
g[v].push_back({u, w});
}
dfs(0);
while (q--) {
int a, b;
cin >> a >> b;
vector<int> u(a), v(b);
for (int &x : u) cin >> x;
for (int &x : v) cin >> x;
long long ans = 1e18;
for (int i : u)
for (int j : v)
ans = min(ans, dist(i, j));
cout << ans << '\n';
}
}
Compilation message
/usr/bin/ld: /tmp/cc6bJEE5.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccEpVV14.o:factories.cpp:(.text.startup+0x0): first defined here
/usr/bin/ld: /tmp/cc6bJEE5.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
