#include <bits/stdc++.h>
#define endl '\n'
using namespace std;
const int maxn = 120010;
int n, m, s[maxn], f[maxn], used[maxn], bef[maxn], p[maxn];
vector<int> v[maxn], paths[maxn];
void dfs(int ver){
used[ver] = 1;
for(int nb : v[ver]){
if(used[nb])
continue;
bef[nb] = ver;
dfs(nb);
}
}
void read(){
cin >> n;
for(int i = 1;i <= n;i++)
v[i].clear();
for(int i = 1;i <= n - 1;i++){
int x, y;
cin >> x >> y;
v[x].push_back(y);
v[y].push_back(x);
}
cin >> m;
for(int i = 1;i <= m;i++){
cin >> s[i] >> f[i];
for(int j = 1;j <= n;j++)
used[j] = 0;
dfs(s[i]);
int x = f[i];
paths[i].clear();
paths[i].push_back(x);
while(x != s[i]){
x = bef[x];
paths[i].push_back(x);
}
reverse(paths[i].begin(), paths[i].end());
}
}
void solve(){
read();
for(int i = 0;i < n;i++){
bool flag = false;
for(int k = 1;k <= m;k++){
if(paths[k].size() > i){
p[paths[k][i]]++;
if(p[paths[k][i]] > 1)
flag = true;
}
}
for(int k = 1;k <= m;k++){
if(paths[k].size() > i)
p[paths[k][i]] = 0;
}
if(flag){
cout << "No\n";
return;
}
}
cout << "Yes\n";
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
int t;
cin >> t;
while(t--){
solve();
}
return 0;
}
Compilation message
jail.cpp: In function 'void solve()':
jail.cpp:52:32: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
52 | if(paths[k].size() > i){
| ~~~~~~~~~~~~~~~~^~~
jail.cpp:59:32: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
59 | if(paths[k].size() > i)
| ~~~~~~~~~~~~~~~~^~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
6748 KB |
Output is correct |
2 |
Correct |
2 ms |
6748 KB |
Output is correct |
3 |
Incorrect |
1 ms |
6748 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
6748 KB |
Output is correct |
2 |
Incorrect |
1 ms |
6748 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
6748 KB |
Output is correct |
2 |
Incorrect |
1 ms |
6748 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
6748 KB |
Output is correct |
2 |
Incorrect |
1 ms |
6748 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
6748 KB |
Output is correct |
2 |
Incorrect |
1 ms |
6748 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
6748 KB |
Output is correct |
2 |
Correct |
1 ms |
6584 KB |
Output is correct |
3 |
Correct |
1 ms |
6748 KB |
Output is correct |
4 |
Incorrect |
1 ms |
6748 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
6748 KB |
Output is correct |
2 |
Correct |
2 ms |
6748 KB |
Output is correct |
3 |
Incorrect |
1 ms |
6748 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |