#include <bits/stdc++.h>
using namespace std;
struct LCA {
int n;
vector<int> depth;
vector<vector<int>> g, dp;
void dfs(int u) {
depth[u] = (u == 0 ? 0 : depth[dp[0][u]] + 1);
for (int i = 0; i + 1 < 20; i++)
dp[i + 1][u] = dp[i][dp[i][u]];
for (int v : g[u])
if (v != dp[0][u]) {
dp[0][v] = u;
dfs(v);
}
}
LCA(vector<vector<int>> g) : g(g) {
n = g.size();
depth.resize(n);
dp.assign(20, vector<int>(n, 0));
dfs(0);
}
int lca(int u, int v) {
if (depth[u] < depth[v])
swap(u, v);
for (int i = 20 - 1; i >= 0; i--)
if (depth[u] - (1 << i) >= depth[v])
u = dp[i][u];
if (u == v)
return u;
for (int i = 20 - 1; i >= 0; i--)
if (dp[i][u] != dp[i][v]) {
u = dp[i][u];
v = dp[i][v];
}
return dp[0][u];
}
int dist(int u, int v) {
return depth[u] + depth[v] - 2 * depth[lca(u, v)];
}
};
void solve() {
int n;
cin >> n;
vector<vector<int>> g(n);
for (int i = 0; i < n - 1; i++) {
int u, v;
cin >> u >> v;
u--, v--;
g[u].push_back(v);
g[v].push_back(u);
}
int m;
cin >> m;
vector<pair<int, int>> p(m);
for (auto &[a, b] : p) {
cin >> a >> b;
a--, b--;
}
vector<int> order(n);
iota(order.begin(), order.end(), 0);
LCA l(g);
do {
vector<bool> occupied(n, false);
for (auto [a, b] : p)
occupied[a] = true;
bool bad = false;
for (int i : order) {
auto [a, b] = p[i];
int lca = l.lca(a, b);
vector<int> p1, p2;
while (a != lca) {
p1.push_back(a);
a = l.dp[0][a];
}
while (b != lca) {
p2.push_back(b);
b = l.dp[0][b];
}
p2.push_back(lca);
reverse(p2.begin(), p2.end());
vector<int> path;
for (int v : p1)
path.push_back(v);
for (int v : p2)
path.push_back(v);
int k = path.size();
for (int j = 0; j + 1 < k; j++)
if (occupied[path[j + 1]])
bad = true;
occupied[path[0]] = false;
occupied[path.back()] = true;
}
if (!bad) {
cout << "Yes\n";
return;
}
} while (next_permutation(order.begin(), order.end()));
cout << "No\n";
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int q;
cin >> q;
while (q--)
solve();
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
28 ms |
316 KB |
Output is correct |
2 |
Runtime error |
1 ms |
468 KB |
Execution killed with signal 11 |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
28 ms |
324 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Runtime error |
1 ms |
588 KB |
Execution killed with signal 11 |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
28 ms |
324 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Runtime error |
1 ms |
588 KB |
Execution killed with signal 11 |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
28 ms |
324 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Runtime error |
1 ms |
588 KB |
Execution killed with signal 11 |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
28 ms |
324 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Runtime error |
1 ms |
588 KB |
Execution killed with signal 11 |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
29 ms |
320 KB |
Output is correct |
2 |
Correct |
0 ms |
324 KB |
Output is correct |
3 |
Runtime error |
1 ms |
452 KB |
Execution killed with signal 11 |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
28 ms |
316 KB |
Output is correct |
2 |
Runtime error |
1 ms |
468 KB |
Execution killed with signal 11 |
3 |
Halted |
0 ms |
0 KB |
- |