#include <bits/stdc++.h>
using namespace std;
int N, M;
int glob, L[100001], R[100001], DIST[100001], UP[20][100001];
int FT[100001];
int DP[2][100001];
vector <int> VG[100001];
vector <array <int, 3>> V[100001];
void Add(int i, int x)
{
for(; i <= N; i += i & (-i)) FT[i] += x;
return;
}
int Sum(int i)
{
int ret = 0;
for(; i; i -= i & (-i)) ret += FT[i];
return ret;
}
void EDFS(int node, int parent = 0)
{
L[node] = ++glob;
for(int i = 0; i < (VG[node].size() - 1); i++) if(VG[node][i] == parent) swap(VG[node][i], VG[node].back());
if(parent) VG[node].pop_back();
UP[0][node] = parent;
for(int i = 1; UP[i - 1][node]; i++) UP[i][node] = UP[i - 1][UP[i - 1][node]];
for(int x : VG[node]) {DIST[x] = DIST[node] + 1; EDFS(x, node);}
R[node] = glob;
return;
}
int LCA(int u, int v)
{
if(DIST[u] > DIST[v]) swap(u, v);
for(int i = 16; i >= 0; i--) if(UP[i][v] && (DIST[UP[i][v]] >= DIST[u])) v = UP[i][v];
if(u == v) return u;
for(int i = 16; i >= 0; i--) if(UP[i][u] && UP[i][v] && (UP[i][u] ^ UP[i][v])) {u = UP[i][u]; v = UP[i][v];}
return UP[0][u];
}
int BS(int u, int v)
{
if((L[u] > L[v]) || (R[u] < R[v])) exit(333);
int l = 0, r = VG[u].size() - 1, s, ret;
while(l <= r)
{
s = (l + r) >> 1;
if(L[VG[u][s]] <= L[v]) {l = s + 1; ret = s;}
else r = s - 1;
}
return VG[u][ret];
}
void DPDFS(int node)
{
for(int x : VG[node])
{
DPDFS(x);
DP[1][node] += DP[0][x];
}
DP[0][node] = DP[1][node];
for(auto a : V[node])
{
// cout << node << ":\n";
int dp = DP[1][node] + a[2];
if(a[0] ^ node)
{
dp -= DP[0][BS(node, a[0])];
dp += Sum(L[a[0]]) + DP[1][a[0]];
// cout << a[0] << ' ' << BS(node, a[0]) << ' ' << dp << '\n';
}
if(a[1] ^ node)
{
dp -= DP[0][BS(node, a[1])];
dp += Sum(L[a[1]]) + DP[1][a[1]];
// cout << a[1] << ' ' << BS(node, a[1]) << ' ' << dp << '\n';
}
// cout << dp << '\n';
DP[0][node] = max(dp, DP[0][node]);
}
// cout << node << ' ' << DP[0][node] << ' ' << DP[1][node] << '\n';
for(int x : VG[node])
{
Add(L[x], DP[1][node] - DP[0][x]);
Add(R[x] + 1, DP[0][x] - DP[1][node]);
}
return;
}
int main()
{
ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
cin >> N;
int u, v, w;
for(int i = 1; i < N; i++)
{
cin >> u >> v;
VG[u].push_back(v);
VG[v].push_back(u);
}
EDFS(1);
cin >> M;
for(int i = 1; i <= M; i++)
{
cin >> u >> v >> w;
V[LCA(u, v)].push_back({u, v, w});
}
DPDFS(1);
cout << DP[0][1] << '\n';
return 0;
}
