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;
#define F first
#define S second
#define endl '\n'
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const int N = 1.2e5 + 50;
const int M = 5e6 + 50, LG = 20;
int n, om, m, par[LG][N], h[N], id[LG][N][2], mark[N][2];
int s[M], t[M];
int d[M];
vector<int> adj[N];
vector<int> adj2[M];
queue<int> q;
void dfs(int u, int p) {
h[u] = h[p]+1;
par[0][u] = p;
if (mark[u][0]) {
adj2[id[0][u][0]].push_back(mark[u][0]);
d[mark[u][0]]++;
}
if (mark[u][1]) {
adj2[mark[u][1]].push_back(id[0][u][1]);
d[id[0][u][1]]++;
}
for (int v:adj[u]) {
if (v == p) continue;
dfs(v, u);
}
}
int Par(int u, int x) {
for (int k = 0; k < LG; k++) {
if (x>>k&1) u = par[k][u];
}
return u;
}
int LCA(int u, int v) {
if (h[u] > h[v]) swap(u, v);
v = Par(v, h[v]-h[u]);
for (int k = LG-1; k >= 0; k--){
if (par[k][u] != par[k][v]) {
u = par[k][u];
v = par[k][v];
}
}
if (u == v) return u;
return par[0][u];
}
void solve() {
cin >> n;
for (int i = 1; i <= n-1; i++) {
int u, v;
cin >> u >> v;
adj[u].push_back(v);
adj[v].push_back(u);
}
cin >> m;
om = m;
for (int i = 1; i <= m; i++) {
cin >> s[i] >> t[i];
mark[s[i]][0] = mark[t[i]][1] = i;
}
for (int k = 0; k < LG; k++) {
for (int u = 1; u <= n; u++) {
id[k][u][0] = ++m;
}
}
for (int k = 0; k < LG; k++) {
for (int u = 1; u <= n; u++) {
id[k][u][1] = ++m;
}
}
dfs(1, 0);
for (int k = 1; k < LG; k++) {
for (int u = 1; u <= n; u++) {
par[k][u] = par[k-1][par[k-1][u]];
adj2[id[k][u][0]].push_back(id[k-1][u][0]);
d[id[k-1][u][0]]++;
adj2[id[k][u][0]].push_back(id[k-1][par[k-1][u]][0]);
d[id[k-1][par[k-1][u]][0]]++;
adj2[id[k-1][u][1]].push_back(id[k][u][1]);
d[id[k][u][1]]++;
adj2[id[k-1][par[k-1][u]][1]].push_back(id[k][u][1]);
d[id[k][u][1]]++;
}
}
for (int i = 1; i <= om; i++) {
int r = LCA(s[i], t[i]);
int u, x;
u = par[0][s[i]];
x = h[u]-h[r]+1;
for (int k = 0; k < LG; k++) {
if (x>>k&1) {
adj2[i].push_back(id[k][u][0]);
d[id[k][u][0]]++;
u = par[k][u];
}
}
u = s[i];
x = h[u]-h[r] + (r != t[i]);
for (int k = 0; k < LG; k++) {
if (x>>k&1) {
adj2[id[k][u][1]].push_back(i);
d[i]++;
u = par[k][u];
}
}
u = t[i];
x = h[u]-h[r] + (r != s[i]);
for (int k = 0; k < LG; k++) {
if (x>>k&1) {
adj2[i].push_back(id[k][u][0]);
d[id[k][u][0]]++;
u = par[k][u];
}
}
u = par[0][t[i]];
x = h[u]-h[r]+1;
for (int k = 0; k < LG; k++) {
if (x>>k&1) {
adj2[id[k][u][1]].push_back(i);
d[i]++;
u = par[k][u];
}
}
}
for (int u = 1; u <= m; u++) {
if (!d[u]) q.push(u);
}
while (q.size()) {
int u = q.front();
q.pop();
for (int v:adj2[u]) {
d[v]--;
if (!d[v]) q.push(v);
}
}
bool flg = 1;
for (int u = 1; u <= m; u++) {
flg = flg&&(!d[u]);
}
cout << (flg?"Yes":"No") << endl;
for (int u = 0; u <= n; u++) {
h[u] = 0;
adj[u].clear();
mark[u][0] = mark[u][1] = 0;
for (int k = 0; k < LG; k++) {
par[k][u] = 0;
id[k][u][0] = 0;
id[k][u][1] = 0;
}
}
for (int u = 0; u <= m; u++) {
adj2[u].clear();
s[u] = t[u] = 0;
d[u] = 0;
}
m = om = 0;
}
int main() {
ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
int tc;
cin >> tc;
while(tc--)
solve();
return 0;
}
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