1 #include<cstring>
 2 #include<cstdio>
 3 #include<cstdlib>
 4 #include<vector>
 5 #include<algorithm>
 6 #include<iostream>
 7 using namespace std;
 8 const int maxn=40100;
 9  struct node
10 {
11   int id,val;
12 };
13 bool vis[maxn];
14 vector< node >map[maxn];
15 node tem;
16 int n,m,ans,cnt;
17 void dfs(int a,int b)
18 {
19 
20    if(a==b){
21        if(ans>cnt)ans=cnt;
22        return ;
23    }
24    int Size=map[a].size();
25       vis[a]=1;
26    for(int i=0;i<Size;i++){
27     if(!vis[map[a][i].id]){
28      cnt+=map[a][i].val;
29      dfs(map[a][i].id,b);
30      cnt-=map[a][i].val;
31     }
32    }
33    vis[a]=0;
34 }
35 int main()
36 {
37     int cas,a,b,val;
38     cin>>cas;
39    while(cas--){
40      cin>>n>>m;
41      cnt=0;
42     for(int i=1;i<=n;i++)
43         map[i].clear();
44    for(int i=1;i<n;i++){
45       scanf("%d%d%d",&a,&b,&val);
46 
47       tem=(node){b,val};
48       map[a].push_back(tem);  //ÎÞÏòͼ
49       tem=(node){a,val};
50       map[b].push_back(tem);
51    }
52    for(int i=0;i<m;i++)
53    {
54         ans=0x3f3f3f3f;
55          scanf("%d%d",&a,&b);
56          dfs(a,b);
57          printf("%d\n",ans);
58    }
59     }
60  return 0;
61 }