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>
#include <random>
#ifndef LOCAL
//#pragma GCC optimize("O3")
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC target("avx,avx2,bmi,bmi2,popcnt,lzcnt")
#endif
using namespace std;
typedef long long ll;
typedef double dd;
typedef long double ld;
typedef unsigned int uii;
#define x first
#define y second
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
void solve();
mt19937_64 mt(1);
int32_t main() {
#ifdef LOCAL
freopen("input.in", "r", stdin);
freopen("output.out", "w", stdout);
#else
ios::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
//freopen("amusing.in", "r", stdin);
//freopen("amusing.out", "w", stdout);
#endif
cout << fixed << setprecision(30);
int tests = 1;
cin >> tests;
while (tests--) {
solve();
}
}
int tim = 0;
bool ans = true;
void dfs(int s, int p, vector<vector<int>>& g, vector<int>& tin, vector<int>& tout, vector<int>& pr) {
tin[s] = tim++;
pr[s] = p;
for (int i : g[s]) {
if (i != p) {
dfs(i, s, g, tin, tout, pr);
}
}
tout[s] = tim++;
}
void find_cycle(int s, vector<vector<int>>& g, vector<int>& used) {
used[s] = 1;
for (int i : g[s]) {
if (used[i] == 1) {
ans = false;
}
if (!used[i]) {
find_cycle(i, g, used);
}
}
used[s] = 2;
}
bool a_p_b(int a, int b, vector<int>& tin, vector<int>& tout) {
return tin[a] <= tin[b] && tout[a] >= tout[b];
}
struct path {
int u, v;
};
void solve() {
tim = 0;
int n;
cin >> n;
vector<vector<int>> g(n);
for (int i = 0; i < n - 1; i++) {
int u, v;
cin >> u >> v; v--; u--;
g[v].push_back(u);
g[u].push_back(v);
}
vector<int> s(n, -1), t(n, -1), tin(n), tout(n), pr(n), cnt(n, 0);
dfs(0, -1, g, tin, tout, pr);
int q;
cin >> q;
ans = true;
vector<int> u, used(q, 0);
vector<path> z;
vector<vector<int>> h(q);
for (int i = 0; i < q; i++) {
int a, b;
cin >> a >> b; a--; b--;
s[a] = i;
t[b] = i;
z.push_back({a, b});
}
for (int ii = 0; ii < q; ii++) {
int a, b;
a = z[ii].u;
b = z[ii].v;
int a1 = a, b1 = b;
while (!a_p_b(a1, b, tin, tout)) {
if (s[a1] != -1) {
cnt[s[a1]] += 2;
u.push_back(s[a1]);
}
if (t[a1] != -1) {
cnt[t[a1]]++;
u.push_back(t[a1]);
}
a1 = pr[a1];
}
while (!a_p_b(b1, a, tin, tout)) {
if (s[b1] != -1) {
cnt[s[b1]] += 2;
u.push_back(s[b1]);
}
if (t[b1] != -1) {
cnt[t[b1]]++;
u.push_back(t[b1]);
}
b1 = pr[b1];
}
if (s[b1] != -1) {
cnt[s[b1]] += 2;
u.push_back(s[b1]);
}
if (t[b1] != -1) {
cnt[t[b1]]++;
u.push_back(t[b1]);
}
for (int i : u) {
if (!cnt[i]) {
continue;
}
if (cnt[i] == 2) {
if (a_p_b(a, z[i].v, tin, tout) ^ a_p_b(a, b, tin, tout)) {
cout << "No\n";
return;
}
}
if (cnt[i] == 1) {
if (a_p_b(b, z[i].u, tin, tout) ^ a_p_b(b, a, tin, tout)) {
cout << "No\n";
return;
}
}
if (cnt[i] > 2 && i != ii) {
cout << "No\n";
return;
}
cnt[i] = 0;
}
u.clear();
}
for (int ii = 0; ii < q; ii++) {
int a, b;
a = z[ii].u;
b = z[ii].v;
int a1 = a, b1 = b, cnt1 = 0;
do {
cnt1++;
if (s[a1] != -1) {
cnt[s[a1]] += 2;
u.push_back(s[a1]);
}
if (t[a1] != -1) {
cnt[t[a1]]++;
u.push_back(t[a1]);
}
a1 = pr[a1];
} while (!a_p_b(a1, b, tin , tout) && cnt1 < 100);
cnt1 = 0;
do {
cnt1++;
if (s[b1] != -1) {
cnt[s[b1]] += 2;
u.push_back(s[b1]);
}
if (t[b1] != -1) {
cnt[t[b1]]++;
u.push_back(t[b1]);
}
b1 = pr[b1];
} while (!a_p_b(b1, a, tin, tout) && cnt1 < 100);
if (b1 != a) {
if (s[b1] != -1) {
cnt[s[b1]] += 2;
u.push_back(s[b1]);
}
if (t[b1] != -1) {
cnt[t[b1]]++;
u.push_back(t[b1]);
}
}
for (int i : u) {
if (!cnt[i]) {
continue;
}
if (cnt[i] == 2) {
h[ii].push_back(i);
}
if (cnt[i] == 1) {
h[i].push_back(ii);
}
cnt[i] = 0;
}
u.clear();
}
ans = true;
for (int i = 0; i < q; i++) {
if (!used[i]) {
find_cycle(i, h, used);
if (!ans) {
cout << "No\n";
return;
}
}
}
if (ans) {
cout << "Yes\n";
} else {
cout << "No\n";
}
}
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