#include <bits/stdc++.h>
constexpr int N = 1e5;
struct segtree{
std::vector<int> t;
int n;
segtree(int n) : n(n), t(2 * n) { }
void update(int p, int val) {
for (t[p += n] = val; p > 1; p >>= 1) {
t[p >> 1] = t[p] + t[p ^ 1];
}
}
int get(int l, int r) {
int res = 0;
for (l += n, r += n; l <= r; l >>= 1, r >>= 1) {
if (l % 2 == 1) res += t[l++];
if (r % 2 == 0) res += t[r--];
}
return res;
}
} dpsum(N), childsum(N);
std::vector<int> e[N];
int n, m, in[N], out[N], up[N][20], timeStamp, siz[N], heavy[N], D[N], par[N], head[N], pos[N];
void precalc(int u, int p, int d = 0) {
par[u] = p;
D[u] = d;
siz[u] = 1;
in[u] = timeStamp++;
up[u][0] = p;
for (int i = 1; i < 20; i++) {
up[u][i] = up[up[u][i - 1]][i - 1];
}
int mx_size = 0;
for (auto v : e[u]) {
if (v != p) {
precalc(v, u, d + 1);
siz[u] += siz[v];
if (mx_size < siz[v]) {
mx_size = siz[v];
heavy[u] = v;
}
}
}
out[u] = timeStamp;
}
bool is(int u, int v) { return in[u] <= in[v] && out[u] >= out[v]; }
int lca(int u, int v) {
if (is(u, v)) return u;
if (is(v, u)) return v;
for (int i = 19; i >= 0; i--) {
if (!is(up[u][i], v)) {
u = up[u][i];
}
}
return up[u][0];
}
void dfs(int u, int h) {
head[u] = h;
pos[u] = timeStamp++;
if (~heavy[u]) {
dfs(heavy[u], h);
}
for (auto v : e[u]) {
if (v != par[u] && v != heavy[u]) {
dfs(v, v);
}
}
}
int queryChild(int u, int v) {
int res = 0;
for (; head[u] != head[v]; v = par[head[v]]) {
if (D[head[u]] > D[head[v]]) {
std::swap(u, v);
}
res += childsum.get(pos[head[v]], pos[v]);
}
if (D[u] > D[v]) {
std::swap(u, v);
}
res += childsum.get(pos[u], pos[v]);
return res;
}
int queryDp(int u, int v) {
int res = 0;
for (; head[u] != head[v]; v = par[head[v]]) {
if (D[head[u]] > D[head[v]]) {
std::swap(u, v);
}
res += dpsum.get(pos[head[v]], pos[v]);
}
if (D[u] > D[v]) {
std::swap(u, v);
}
res += dpsum.get(pos[u], pos[v]);
return res;
}
std::vector<std::tuple<int, int, int>> q[N];
int dp[N];
void calc(int u) {
int chsum = 0;
for (auto v : e[u]) {
if (v != par[u]) {
calc(v);
chsum += dp[v];
}
}
childsum.update(pos[u], chsum);
dp[u] = chsum;
for (auto [a, b, c] : q[u]) {
int res = 0;
res += queryChild(a, b);
res -= queryDp(a, b);
res += c;
dp[u] = std::max(dp[u], res);
}
dpsum.update(pos[u], dp[u]);
}
int main() {
std::ios::sync_with_stdio(false);
std::cin.tie(nullptr);
std::cin >> n;
for (int i = 0; i < n - 1; i++) {
int u, v;
std::cin >> u >> v;
u--;
v--;
e[u].push_back(v);
e[v].push_back(u);
}
memset(heavy, -1, sizeof heavy);
precalc(0, 0);
timeStamp = 0;
dfs(0, 0);
std::cin >> m;
for (int i = 0; i < m; i++) {
int u, v, c;
std::cin >> u >> v >> c;
u--;
v--;
q[lca(u, v)].emplace_back(u, v, c);
}
calc(0);
std::cout << dp[0] << "\n";
return 0;
}
