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;
typedef long long ll;
const int N = 24e4 + 2, MOD = (int)1e9+7;
int n,x[N],y[N],m,it = 1,it1 = 1,s[N],f[N];
vector<int> g[N],G[N * 20];
int up[N][20],t[N][20],t1[N][20],tin[N],tout[N],timer = 0;
const int b = 18;
void dfs(int v,int pr) {
tin[v] = ++timer;
up[v][0] = pr;
if(!x[v]) {
t[v][0] = ++it;
} else {
t[v][0] = x[v];
}
if(!y[v]) {
t1[v][0] = ++it;
} else {
t1[v][0] = y[v];
}
for(int i = 1;i <= b;i++) {
up[v][i] = up[up[v][i-1]][i-1];
t[v][i] = ++it;
t1[v][i] = ++it;
// cout << t[v][i] << ' ' << t[v][i - 1] << "\n" ;
// cout << t[v][i] << ' ' << t[up[v][i-1]][i - 1] << '\n';
G[t[v][i]].push_back(t[v][i-1]);G[t[v][i]].push_back(t[up[v][i-1]][i-1]);
G[t1[v][i-1]].push_back(t1[v][i]);G[t1[up[v][i-1]][i-1]].push_back(t1[v][i]);
}
for(int to:g[v]) {
if(to == pr) continue;
dfs(to,v);
}
tout[v] = ++timer;
}
int vis[N * 20];
bool ans = 1;
void go(int v) {
vis[v] = 1;
for(int to:G[v]) {
if(!vis[to]) {
// cout << v << ' ' << to << '\n';
go(to);
} else {
if(vis[to] == 1) {
ans = 0;
}
}
}
vis[v] = 2;
}
bool is(int v,int u) {
return (tin[v] <= tin[u] && tout[v] >= tout[u]);
}
int lca(int v,int u) {
if(is(v,u)) return v;
if(is(u,v)) return u;
for(int i = b;i >= 0;i--) {
if(!is(up[v][i],u)) {
v = up[v][i];
}
}
return up[v][0];
}
void add(int v,int l,int id,bool ok) {
if(!is(l,v) || (l == v && ok)) return;
for(int i = b;i >= 0;i--) {
if(!is(up[v][i],l)) {
G[id].push_back(t[v][i]);
v = up[v][i];
}
}
if(ok)G[id].push_back(t[v][1]);
else{
G[id].push_back(t[v][0]);
}
}
void add_(int v,int l,int id,bool ok) {
// if(!is(l,v) || (l == v && ok)) return;
// cout << v << ' ' << l << ' ' << id << ' ' << ok << '\n';
// cout << v << ' ' << l << "x\n";
for(int i = b;i >= 0;i--) {
if(!is(up[v][i],l)) {
// cout << t1[v][i] << ' ' << id << '\n';
G[t1[v][i]].push_back(id);
v = up[v][i];
}
}
// cout << t1[v][1] << ' ' << id << '\n';
// cout << "x\n";
if(ok)G[t1[v][1]].push_back(id);
else{
G[t1[v][0]].push_back(id);
// cout << t1[v][0] << ' ' << id << '\n';
}
}
void test() {
ans = 1;
timer = 0;
cin >> n;
for(int i = 1;i <= n;i++) {
g[i].clear();
x[i] = y[i] =0 ;
}
for(int i = 1;i <= n - 1;i++) {
int a,b;
cin >> a >> b;
g[a].push_back(b);
g[b].push_back(a);
}
cin >> m;
it = it1 = m;
for(int i = 1;i <= m;i++) {
cin >> s[i] >> f[i];
y[f[i]] = x[s[i]] = i;
}
dfs(1,1);
for(int i = 1;i <= m;i++) {
int l = lca(s[i],f[i]);
if(s[i] == l) {
add(f[i],l,i,0);
} else {
add(up[s[i]][0],l,i,1);
if(f[i] != l) add(f[i],l,i,1);
}
if(f[i] == l) {
add_(s[i],l,i,0);
} else {
add_(up[f[i]][0],l,i,1);
if(s[i] != l) add_(s[i],l,i,1);
}
}
for(int i = 1;i <= it;i++) {
if(!vis[i]) {
go(i);
}
}
cout << (ans ? "Yes\n":"No\n");
for(int i = 1;i <= it;i++) {
G[i].clear();
vis[i] =0;
}
}
int main() {
ios_base::sync_with_stdio(false);cin.tie(0);
int t = 1;
cin >> t;
while(t--) {
test();
}
}
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