This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
const int N=1e5+5;
int n,m;
vector<int>g[N];
int tab[23][N];
int depth[N];
int pos=0;
int in[N];
int out[N];
void DFS(int u,int par) {
pos++;
in[u]=pos;
for(auto v:g[u])
if(v!=par) {
tab[0][v]=u;
depth[v]=depth[u]+1;
DFS(v,u);
}
out[u]=pos;
}
void init() {
depth[1]=1;
DFS(1,0);
for(int i=1; i<=20; i++)
for(int j=1; j<=n; j++)
tab[i][j]=tab[i-1][tab[i-1][j]];
}
int LCA(int u,int v) {
if(depth[u]<depth[v])swap(u,v);
for(int i=20; i>=0; i--)if(depth[tab[i][u]]>=depth[v])u=tab[i][u];
if(u==v)return u;
for(int i=20; i>=0; i--)if(tab[i][u]!=tab[i][v]) {
v=tab[i][v];
u=tab[i][u];
}
return tab[0][u];
}
long long dp[N];
struct event {
int u,v,c;
};
vector<event>save[N];
long long aib[N];
void add(int i, int x) {
while (i <N) {
aib[i] += x;
i += i & (-i);
}
}
long long get(int i) {
int sol = 0;
while (i) {
sol += aib[i];
i -= i & (-i);
}
return sol;
}
long long sum[N];
void DFS_ans(int u,int par) {
for(auto v:g[u])
if(v!=par) {
DFS_ans(v,u);
sum[u]+=dp[v];
}
dp[u]=sum[u];
for(auto v:save[u]) {
dp[u]=max(dp[u],get(in[v.u])+get(in[v.v])+v.c+sum[u]);
}
add(in[u],sum[u]-dp[u]);
add(out[u]+1,dp[u]-sum[u]);
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin>>n;
for(int i=1; i<n; i++) {
int u,v;
cin>>u>>v;
g[u].push_back(v);
g[v].push_back(u);
}
init();
cin>>m;
while(m--) {
int u,v,c;
cin>>u>>v>>c;
save[LCA(u,v)].push_back({u,v,c});
}
DFS_ans(1,0);
cout<<dp[1];
return 0;
}
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