#include<bits/stdc++.h>
using namespace std;
#define task "a"
#define se second
#define fi first
#define ll long long
#define ii pair<int, int>
#define tp tuple<int, int, int>
const long mxN = 1e5 + 7;
int n, h[mxN], in[mxN], out[mxN], par[mxN][25], tree[mxN * 4], dp[mxN][2], num;
vector<int> w[mxN];
vector<tp> querry[mxN];
void Build(int j)
{
in[j] = ++num;
h[j] = h[par[j][0]] + 1;
for (int i = 1; i <= 19; i++)
par[j][i] = par[par[j][i - 1]][i - 1];
for (int i : w[j])
{
if (h[i])
continue;
par[i][0] = j;
Build(i);
}
out[j] = num;
}
int LCA(int u, int v)
{
if (h[u] < h[v])
swap(u, v);
for (int i = 19; i >= 0; i--)
{
if (h[par[u][i]] >= h[v])
u = par[u][i];
}
if (u == v)
return u;
for (int i = 19; i >= 0; i--)
{
if (par[u][i] != par[v][i])
{
u = par[u][i];
v = par[v][i];
}
}
return par[u][0];
}
int Get(int vt, int j = 1, int l = 1, int r = n)
{
if (l > vt || vt > r)
return 0;
if (l == r)
return tree[j];
int mid = (l + r) / 2;
return Get(vt, j * 2, l, mid) + Get(vt, j * 2 + 1, mid + 1, r) + tree[j];
}
void Upd(int u, int v, int val, int j = 1, int l = 1, int r = n)
{
if (u > r || l > v)
return;
if (u <= l && r <= v)
{
tree[j] += val;
return;
}
int mid = (l + r) / 2;
Upd(u, v, val, j * 2, l, mid);
Upd(u, v, val, j * 2 + 1, mid + 1, r);
}
void DFS(int j)
{
for (int i : w[j])
{
if (i == par[j][0])
continue;
DFS(i);
dp[j][0] += dp[i][1];
}
dp[j][1] = dp[j][0];
for (auto [u, v, val] : querry[j])
dp[j][1] = max(dp[j][1], dp[j][0] + Get(in[u]) + Get(in[v]) + val);
Upd(in[j], out[j], dp[j][0] - dp[j][1]);
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
//freopen(task".INP", "r", stdin);
//freopen(task".OUT", "w", stdout);
cin >> n;
for (int i = 1; i < n; i++)
{
int u, v;
cin >> u >> v;
w[u].push_back(v);
w[v].push_back(u);
}
Build(1);
int q;
cin >> q;
for (int i = 1; i <= q; i++)
{
int u, v, val;
cin >> u >> v >> val;
int root = LCA(u, v);
querry[root].push_back({u, v, val});
}
DFS(1);
cout << dp[1][1];
}
