#include <cstdio>
#include <stdio.h>
#include <stdbool.h>
#include <iostream>
#include <map>
#include <vector>
#include <climits>
#include <stack>
#include <string>
#include <queue>
#include <algorithm>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <cmath>
#include <cctype>
#include <bitset>
#include <iomanip>
#include <cstring>
#include <numeric>
#include <cassert>
#include <random>
using namespace std;
#define int long long
#define pii pair<int, int>
#define mp make_pair
#define pb push_back
#define fi first
#define se second
int counter=0;
vector<int> depth, in, out, dp, ft;
vector<vector<int> > graph, twok;
vector<vector<pair<pii, int> > > quer;
int query(int i){
int res=0;
for (;i;i-=i&-i)res+=ft[i];
return res;
}
void up(int i, int v){
for (;i<ft.size();i+=i&-i)ft[i]+=v;
}
void dfs(int node, int p, int d){
in[node]=++counter;
twok[node][0]=p;
depth[node]=d;
for (int i=1; i<20; ++i)twok[node][i]=twok[twok[node][i-1]][i-1];
for (auto num:graph[node])if (num!=p)dfs(num, node, d+1);
out[node]=counter;
}
int lca(int a, int b){
if (depth[a]<depth[b])swap(a, b);
for (int i=0, k=depth[a]-depth[b]; i<20; ++i)if (k&(1<<i))a=twok[a][i];
if (a==b)return a;
for (int i=19; i>=0; --i)if (twok[a][i]!=twok[b][i])a=twok[a][i], b=twok[b][i];
return twok[a][0];
}
void dfs2(int node, int p){
int sum=0;
for (auto num:graph[node])if (num!=p)dfs2(num, node), sum+=dp[num];
for (auto c:quer[node])dp[node]=max(dp[node], query(in[c.fi.fi])+query(in[c.fi.se])+sum+c.se);
dp[node]=max(dp[node], sum);
up(in[node], sum-dp[node]);
up(out[node]+1, dp[node]-sum);
}
int32_t main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n, m, a, b, c;
cin>>n;
ft.resize(n+1, 0);
dp.resize(n+1, 0);
graph.resize(n+1);
twok.resize(n+1, vector<int>(20));
in.resize(n+1);
out.resize(n+1);
depth.resize(n+1);
quer.resize(n+1);
for (int i=1; i<n; ++i){
cin>>a>>b;
graph[a].pb(b);
graph[b].pb(a);
}
dfs(1, 1, 0);
cin>>m;
while (m--)cin>>a>>b>>c, quer[lca(a, b)].pb(mp(mp(a, b), c));
dfs2(1, 1);
cout<<dp[1];
}
