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 MX=1.2e5+5;
int Q,N,M;
int S[MX], T[MX];
vector<int> adj[MX], cyc[MX*40];
int up[MX][20], dep[MX], deg[MX*40];
int timer=0,tin[MX],tout[MX];
int valS[MX], valT[MX];
int idS[MX][20], idT[MX][20];
void dfs(int v, int p) {
tin[v]=++timer;
up[v][0]=p;
for(int k=1;k<18;k++) {
up[v][k]=up[up[v][k-1]][k-1];
}
for(auto u:adj[v]) {
if(u==p) continue;
dep[u]=dep[v]+1;
dfs(u,v);
}
tout[v]=timer;
}
bool isAnc(int u, int v) { // u is the ancestor
return tin[u]<=tin[v] && tout[v]<=tout[u];
}
int getLCA(int u, int v) {
if(isAnc(u,v)) return u;
if(isAnc(v,u)) return v;
for(int k=0;k<18;k++) {
if(up[u][k]!=0 && !isAnc(up[u][k],v)) {
u=up[u][k];
}
}
return up[u][0];
}
int main() {
cin.tie(0); ios_base::sync_with_stdio(0);
cin>>Q;
while(Q--) {
cin>>N;
for(int i=1;i<=N;i++) {
valS[i]=-1;
valT[i]=-1;
dep[i]=0;
adj[i].clear();
for(int j=0;j<18;j++) {
up[i][j]=0;
idS[i][j]=0;
idT[i][j]=0;
}
}
for(int i=0;i<N-1;i++) {
int u,v;
cin>>u>>v;
adj[u].push_back(v);
adj[v].push_back(u);
}
tin[0]=0;
tout[0]=1e9;
timer=0;
dfs(1,0);
cin>>M;
int id=M;
for(int i=1;i<=N;i++) {
for(int j=0;j<18;j++) {
idS[i][j]=id++;
}
for(int j=0;j<17;j++) {
cyc[idS[i][j]].push_back(idS[i][j+1]);
if(j>0 && up[i][j-1]!=0) cyc[idS[up[i][j-1]][j]].push_back(idS[i][j+1]);
}
}
for(int i=1;i<=N;i++) {
for(int j=0;j<18;j++) {
idT[i][j]=id++;
}
for(int j=0;j<17;j++) {
cyc[idT[i][j+1]].push_back(idT[i][j]);
if(j>0 && up[i][j-1]!=0) cyc[idT[i][j+1]].push_back(idT[up[i][j-1]][j]);
}
}
for(int i=0;i<M;i++) {
cin>>S[i]>>T[i];
valS[S[i]]=i;
valT[T[i]]=i;
}
for(int i=0;i<M;i++) {
int L=getLCA(S[i],T[i]);
// everything within par(S[i]) to before L don't have tricky cases
if(dep[S[i]]-dep[L]>=2) {
int v=up[S[i]][0];
for(int k=16;k>=0;k--) {
if(up[v][k]!=0 && !isAnc(up[v][k],L)) {
cyc[idS[v][k+1]].push_back(i);
cyc[i].push_back(idT[v][k+1]);
v=up[v][k];
}
}
}
if(dep[T[i]]-dep[L]>=2) {
int v=up[T[i]][0];
for(int k=16;k>=0;k--) {
if(up[v][k]!=0 && !isAnc(up[v][k],L)) {
cyc[idS[v][k+1]].push_back(i);
cyc[i].push_back(idT[v][k+1]);
v=up[v][k];
}
}
}
// connect to the base
cyc[i].push_back(idS[S[i]][0]);
cyc[idT[T[i]][0]].push_back(i);
// this is for handling the cases on the edge to make sure
// we don't connect i with itself
vector<int> cands={S[i],L,T[i]};
for(auto x:cands) {
// we just naively connect edges since there are <= 3 candidates
if(valS[x]!=-1 && valS[x]!=i) cyc[valS[x]].push_back(i);
if(valT[x]!=-1 && valT[x]!=i) cyc[i].push_back(valT[x]);
}
}
for(int i=0;i<id;i++) {
for(auto j:cyc[i]) {
deg[j]+=1;
}
}
queue<int> q;
for(int i=0;i<id;i++) {
if(!deg[i]) q.push(i);
}
int ans=0;
while(!q.empty()) {
auto v=q.front(); q.pop();
ans+=1;
for(auto u:cyc[v]) {
deg[u]-=1;
if(!deg[u]) q.push(u);
}
}
cout<<(ans==id?"Yes":"No")<<'\n';
for(int i=0;i<id;i++) {
cyc[i].clear();
deg[i]=0;
}
}
}
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