#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 2e4 + 37;
vector<int> adj[N], adj2[N], s(N), e(N), ti(N), to(N), vis(N);
int par[N][18], cnt, flag;
bool ia(int x, int y){
return ti[x] <= ti[y] && to[x] >= to[y];
}
int d(int x, int y){
if(x == y) return 0;
int sum = 0;
if(ia(x, y)) swap(x, y);
for (int i = 17; i >= 0; i--){
if(!ia(par[x][i], y)){
x = par[x][i];
sum += 1<<i;
}
}
sum++;
x=par[x][0];
if(x==y) return sum;
swap(x, y);
for (int i = 17; i >= 0; i--){
if(!ia(par[x][i], y)){
x = par[x][i];
sum += 1<<i;
}
}
sum++;
return sum;
}
bool c(int x, int y){// s1 e2 s2 e2
return(d(s[x], e[x]) == (d(s[x], e[y])+ d(e[y], e[x])));
}
void dfs(int v, int p){
par[v][0] = p;
ti[v] = cnt++;
for (auto i: adj[v]){
if (i == p) continue;
dfs(i, v);
}
to[v] = cnt++;
}
void dfs2(int v, int z){
vis[v] = z;
for (auto i: adj2[v]){
if (i==z-1) flag = 0;
else if(vis[i]!=z) dfs2(i, z);
}
}
void solve(){
int n; cin >> n;
cnt = 0;
for (int i = 1; i < n; i++){
int x, y; cin >> x >> y;
x--; y--;
adj[x].push_back(y);
adj[y].push_back(x);
}
dfs(0, 0);
for (int i = 1; i < 18; i++){
for(int l = 0; l < n; l++){
par[l][i] = par[par[l][i-1]][i-1];
}
}
flag = 1;
int m; cin >> m;
for (int i = 0; i < m; i++){
cin >> s[i] >> e[i];
s[i]--; e[i]--;
}
for (int i = 0; i < m; i++){
for (int l = i+1; l < m; l++){
if (c(i, l)&&c(l, i)) flag=0;
}
}
/* for(int i = 0; i < n; i++){
if(!vis[i]){
dfs2(i, i+1);
}
}
*/
if(flag) cout << "Yes\n";
else cout << "No\n";
for (int i = 0; i < n; i++){
adj[i].clear();
adj2[i].clear();
vis[i] = 0;
}
}
int32_t main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
int t; cin>>t;
while(t--){
solve();
}
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
8276 KB |
Output is correct |
2 |
Correct |
6 ms |
8276 KB |
Output is correct |
3 |
Correct |
6 ms |
8276 KB |
Output is correct |
4 |
Incorrect |
14 ms |
8276 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
8276 KB |
Output is correct |
2 |
Correct |
4 ms |
8276 KB |
Output is correct |
3 |
Incorrect |
5 ms |
8276 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
8276 KB |
Output is correct |
2 |
Correct |
4 ms |
8276 KB |
Output is correct |
3 |
Incorrect |
5 ms |
8276 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
8276 KB |
Output is correct |
2 |
Correct |
4 ms |
8276 KB |
Output is correct |
3 |
Incorrect |
5 ms |
8276 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
8276 KB |
Output is correct |
2 |
Correct |
4 ms |
8276 KB |
Output is correct |
3 |
Incorrect |
5 ms |
8276 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
8276 KB |
Output is correct |
2 |
Incorrect |
4 ms |
8276 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
8276 KB |
Output is correct |
2 |
Correct |
6 ms |
8276 KB |
Output is correct |
3 |
Correct |
6 ms |
8276 KB |
Output is correct |
4 |
Incorrect |
14 ms |
8276 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |