#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 2e5 + 10, MOD = 998244353;
vector<int> g[N], x[N], gt[N];
int timer = 0, tin[N], tout[N], n, m, s[N], t[N], pp[N], val[N], used[N];
void dfs(int v, int pr = 1)
{
tin[v] = ++timer;
pp[v] = pr;
for (int to : g[v])
{
if (to == pr)
continue;
dfs(to, v);
}
tout[v] = ++timer;
}
bool is(int v, int u)
{
return (tin[v] <= tin[u] && tout[v] >= tout[u]);
}
vector<int> path(int v,int u){
vector<int> p(1,v);
while(!is(v,u)){
v = pp[v];
p.push_back(v);
}
while(!is(u,v)){
p.push_back(u);
u = pp[u];
}
return p;
}
bool res = 1;
void dfs1(int v){
used[v] = 1;
for(int to:gt[v]){
if(used[to] == 1){
// cout << v << ' ' << to << '\n';
res =0 ;
}
if(!used[to]){
dfs1(to);
}
}
used[v] = 2;
}
void test()
{
res = 1;
timer = 0;
cin >> n;
for (int i = 1; i <= n; i++)
g[i].clear();
for (int i = 1; i <= n - 1; i++)
{
int x, y;
cin >> x >> y;
g[x].push_back(y);
g[y].push_back(x);
}
dfs(1);
cin >> m;
for(int i = 1;i <= m;i++){
val[i] = 0;
}
for (int i = 1; i <= m; ++i)
{
cin >> s[i] >> t[i];
gt[i].clear();
used[i] = 0;
val[s[i]] = i;
}
for(int i = 1;i <= m;i++){
for(int j:path(s[i],t[i])){
int x = val[j];
if(x && x != i){
gt[x].push_back(i);
// cout << x << ' ' << i << '\n';
}
}
}
for(int i = 1;i <= m;i++){
if(!used[i] && res){
dfs1(i);
}
}
cout << (res ? "Yes\n" : "No\n");
}
main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
int T = 1;
cin >> T;
for (int i = 1; i <= T; i++)
{
test();
}
}
Compilation message
jail.cpp:92:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
92 | main()
| ^~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
19804 KB |
Output is correct |
2 |
Correct |
4 ms |
19808 KB |
Output is correct |
3 |
Correct |
4 ms |
19804 KB |
Output is correct |
4 |
Incorrect |
14 ms |
20060 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
19804 KB |
Output is correct |
2 |
Correct |
5 ms |
19804 KB |
Output is correct |
3 |
Incorrect |
6 ms |
19832 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
19804 KB |
Output is correct |
2 |
Correct |
5 ms |
19804 KB |
Output is correct |
3 |
Incorrect |
6 ms |
19832 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
19804 KB |
Output is correct |
2 |
Correct |
5 ms |
19804 KB |
Output is correct |
3 |
Incorrect |
6 ms |
19832 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
19804 KB |
Output is correct |
2 |
Correct |
5 ms |
19804 KB |
Output is correct |
3 |
Incorrect |
6 ms |
19832 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
19804 KB |
Output is correct |
2 |
Correct |
4 ms |
19804 KB |
Output is correct |
3 |
Correct |
4 ms |
19848 KB |
Output is correct |
4 |
Correct |
4 ms |
19804 KB |
Output is correct |
5 |
Incorrect |
8 ms |
19800 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
19804 KB |
Output is correct |
2 |
Correct |
4 ms |
19808 KB |
Output is correct |
3 |
Correct |
4 ms |
19804 KB |
Output is correct |
4 |
Incorrect |
14 ms |
20060 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |