#include <bits/stdc++.h>
using namespace std;
void setup()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
struct SEGMENT_TREE
{
int tree[400000];
inline void Update(int ind, int l, int r, int x, int y, int v)
{
if (r < x || y < l)
{
return;
}
if (x <= l && r <= y)
{
tree[ind] += v;
return;
}
int m = (l + r) >> 1;
Update(ind << 1, l, m, x, y, v);
Update(ind << 1 | 1, m + 1, r, x, y, v);
}
inline int Get(int ind, int l, int r, int x)
{
if (l == r)
{
return tree[ind];
}
tree[ind << 1] += tree[ind];
tree[ind << 1 | 1] += tree[ind];
tree[ind] = 0;
int m = (l + r) >> 1;
if (x <= m)
{
return Get(ind << 1, l, m, x);
}
return Get(ind << 1 | 1, m + 1, r, x);
}
} st;
int n, m, x[100000], y[100000], a, b, f[100000], h[100000], v[100000];
int head[100000], tail[100000], sp[20][100000];
vector<int> g[100000], q[100000];
inline int LCA(int ina, int inb)
{
if (head[ina] <= head[inb] && tail[inb] <= tail[ina])
{
return ina;
}
for (int i = 19, j; i >= 0; --i)
{
j = sp[i][ina];
if (head[j] > head[inb] || tail[inb] > tail[j])
{
ina = j;
}
}
return sp[0][ina];
}
inline void DFS1(int node, int par)
{
head[node] = a++;
sp[0][node] = par;
for (int i = 1; i < 20; ++i)
{
sp[i][node] = sp[i - 1][sp[i - 1][node]];
}
for (auto &i : g[node])
{
if (i != par)
{
DFS1(i, node);
}
}
tail[node] = a - 1;
}
inline void DFS2(int node, int par)
{
h[node] = 0;
for (auto &i : g[node])
{
if (i != par)
{
DFS2(i, node);
h[node] += f[i];
}
}
f[node] = h[node];
for (auto &i : q[node])
{
f[node] = max(f[node], h[node] + st.Get(1, 1, n, head[x[i]]) + st.Get(1, 1, n, head[y[i]]) + v[i]);
}
st.Update(1, 1, n, head[node], tail[node], h[node] - f[node]);
}
int main()
{
setup();
cin >> n;
for (int i = 0; i < n - 1; ++i)
{
cin >> a >> b;
g[a - 1].push_back(b - 1);
g[b - 1].push_back(a - 1);
}
a = 1;
DFS1(0, 0);
cin >> m;
for (int i = 0; i < m; ++i)
{
cin >> x[i] >> y[i] >> v[i];
x[i]--;
y[i]--;
a = LCA(x[i], y[i]);
q[a].push_back(i);
}
DFS2(0, 0);
cout << f[0];
return 0;
}
