#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int N, Q;
cin >> N >> Q;
vector<int> deg(N);
vector<vector<int>> adj(N);
for (int i = 0; i < N - 1; i++) {
int x, y;
cin >> x >> y;
deg[--x]++;
deg[--y]++;
adj[x].push_back(y);
adj[y].push_back(x);
}
int cnt = 0;
vector<int> v(N), par(N, -1);
auto dfs = [&](auto dfs, int x) -> void {
if (deg[x] == 1) {
v[x] = 1;
}
for (int y : adj[x]) {
if (y == par[x]) {
continue;
}
par[y] = x;
dfs(dfs, y);
v[x] ^= v[y];
}
cnt += v[x];
};
dfs(dfs, 0);
while (Q--) {
int D;
cin >> D;
vector<int> a(D);
for (int &p : a) {
cin >> p;
p--;
if (deg[p]++ != 1) {
int x = p;
while (x != -1) {
cnt += v[x] == 0 ? 1 : -1;
v[x] ^= 1;
x = par[x];
}
}
}
if ((cnt + D) % 2 == 1) {
cout << -1 << "\n";
} else {
cout << 2 * (N - 1) - cnt + D << "\n";
}
for (int p : a) {
if (--deg[p] != 1) {
int x = p;
while (x != -1) {
cnt += v[x] == 0 ? 1 : -1;
v[x] ^= 1;
x = par[x];
}
}
}
}
return 6/22;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
212 KB |
Output is correct |
2 |
Incorrect |
19 ms |
1712 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
852 KB |
Output is correct |
2 |
Correct |
6 ms |
852 KB |
Output is correct |
3 |
Correct |
18 ms |
7308 KB |
Output is correct |
4 |
Correct |
20 ms |
5580 KB |
Output is correct |
5 |
Correct |
25 ms |
7728 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
789 ms |
1108 KB |
Output is correct |
2 |
Correct |
809 ms |
1108 KB |
Output is correct |
3 |
Execution timed out |
1075 ms |
11596 KB |
Time limit exceeded |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Execution timed out |
1073 ms |
2004 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
34 ms |
4860 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
63 ms |
7476 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
212 KB |
Output is correct |
2 |
Incorrect |
19 ms |
1712 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |