#include <bits/stdc++.h>
#define ll long long
#define ull unsigned ll
#define pb push_back
#define pa pair<int, int>
#define pall pair<ll, int>
#define fi first
#define se second
#define TASK "test"
#define Size(x) (int) x.size()
#define all(x) x.begin(), x.end()
using namespace std;
template<typename T1, typename T2> bool mini (T1 &a, T2 b) {if(a > b) a = b; else return 0; return 1;}
template<typename T1, typename T2> bool maxi (T1 &a, T2 b) {if(a < b) a = b; else return 0; return 1;}
const int MOD = 1e9 + 7;
const int LOG = 17;
const int maxn = 1e5 + 7;
const ll oo = 1e9 + 69;
int n, m, u, v, c, dp[maxn], sum[maxn], st[maxn], en[maxn], timer = 0;
vector<int> g[maxn], ev[maxn];
struct query {
int u, v, c;
} que[maxn];
struct LCA {
int p[LOG][maxn], dep[maxn];
void dfs(int u, int par) {
p[0][u] = par;
for(auto v:g[u]) {
if(v == par) continue;
dep[v] = dep[u] + 1;
dfs(v, u);
}
}
int get_lca(int u, int v) {
if(dep[u] < dep[v]) swap(u, v);
int k = dep[u] - dep[v];
for(int i = 0; i < LOG; i++)
if((k >> i) & 1) u = p[i][u];
if(u == v) return u;
for(int i = LOG - 1; i >= 0; i--)
if(p[i][u] != p[i][v]) {
u = p[i][u];
v = p[i][v];
}
return p[0][u];
}
int jump(int u, int k) {
for(int i = 0; i < LOG; i++)
if((k >> i) & 1) u = p[i][u];
return u;
}
void init() {
dep[1] = 0;
dfs(1, 0);
for(int i = 1; i < LOG; i++) {
for(int u = 1; u <= n; u++) p[i][u] = p[i - 1][p[i - 1][u]];
}
}
} lca;
void dfs_st(int u, int par) {
st[u] = ++timer;
for(auto v:g[u]) {
if(v == par) continue;
dfs_st(v, u);
}
en[u] = timer;
}
struct BIT {
int bit[maxn];
void update(int x, int val) {
for(; x <= n; x += x&-x) bit[x] += val;
}
int get(int x) {
int ans = 0;
for(; x; x -= x&-x) ans += bit[x];
return ans;
}
} bit;
int trace(int v, int u) {
int res = 0;
while(v != u) {
res += dp[v] - sum[v];
v = lca.p[0][v];
}
return res;
}
void dfs(int u, int par) {
for(auto v:g[u]) {
if(v == par) continue;
dfs(v, u);
sum[u] += dp[v];
}
maxi(dp[u], sum[u]);
for(auto i:ev[u]) {
int tot = bit.get(st[que[i].u]) + bit.get(st[que[i].v]);
// if(que[i].u != u) tot += trace(que[i].u, u);
// if(que[i].v != u) tot += trace(que[i].v, u);
maxi(dp[u], sum[u] - tot + que[i].c);
}
bit.update(st[u], dp[u] - sum[u]);
bit.update(en[u] + 1, -dp[u] + sum[u]);
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
//freopen(TASK".inp", "r", stdin);
//freopen(TASK".out", "w", stdout);
cin>>n;
for(int i = 1; i < n; i++) {
cin>>u>>v;
g[u].pb(v);
g[v].pb(u);
}
lca.init();
dfs_st(1, 0);
cin>>m;
for(int i = 1; i <= m; i++) {
cin>>que[i].u>>que[i].v>>que[i].c;
ev[lca.get_lca(que[i].u, que[i].v)].pb(i);
}
dfs(1, 0);
cout<<dp[1];
return 0;
}
