1 const int maxn = 4e4 + 5;
2 int T, n, m;
3 int f[maxn], vis[maxn], dis[maxn], ans[maxn];
4 vector<P> vc[maxn];
5 vector<int> query[maxn], id[maxn];
6
7 inline int getf(int v) { return v == f[v] ? v : f[v] = getf(f[v]); }
8
9 inline void Tarjan(int cur) {
10 vis[cur] = 1;
11
12 for (auto son : vc[cur]) {
13 if (vis[son.first]) continue;
14
15 dis[son.first] = dis[cur] + son.second;
16 Tarjan(son.first);
17 f[son.first] = cur;
18 }
19
20 vis[cur] = 2;
21
22 for (int i = 0; i < query[cur].size(); i++) {
23 int v = query[cur][i], t = id[cur][i];
24
25 if (vis[v] == 2) {
26 int lca = getf(v);
27 ans[t] = dis[cur] + dis[v] - 2 * dis[lca];
28 }
29 }
30 }
31
32 int main() {
33 for (read(T); T; T--) {
34 read(n), read(m);
35
36 rep(i, 1, n) {
37 vc[i].clear(), query[i].clear(), id[i].clear();
38 f[i] = i, vis[i] = 0;
39 }
40
41 rep(i, 1, n - 1) {
42 int u, v, cost;
43 read(u), read(v), read(cost);
44 vc[u].push_back({v, cost});
45 vc[v].push_back({u, cost});
46 }
47
48 auto Add_Query = [](int u, int v, int i) {
49 query[u].push_back(v);
50 id[u].push_back(i);
51 };
52
53 rep(i, 1, m) {
54 int u, v;
55 read(u), read(v);
56 Add_Query(u, v, i);
57 if(u != v) Add_Query(v, u, i);
58 }
59
60 Tarjan(1);
61
62 rep(i, 1, m)
63 writeln(ans[i]);
64 }
65 return 0;
66 }
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