#include <bits/stdc++.h>
#define f first
#define s second
using namespace std;
const int N = 2e5 + 69;
int n, q, ch[N], par[N], lf[N], is[N];
vector<int> g[N];
void dfs(int v, int p) {
par[v] = p;
if (g[v].size() == 1)
ch[v] = lf[v] = is[v] = 1;
for (auto u : g[v]) {
if (u == p)
continue;
dfs(u, v);
ch[v] += ch[u];
}
}
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
cin >> n >> q;
for (int i = 1;i <= n - 1;i++) {
int a, b;
cin >> a >> b;
g[a].push_back(b);
g[b].push_back(a);
}
dfs(1, 0);
int uk = ch[1];
while (q--) {
int t;
cin >> t;
int a[t];
for (int i = 0;i < t;i++) {
cin >> a[i];
uk += 1;
if (lf[a[i]]) {
uk -= 1;
lf[a[i]] = 0;
}
int v = a[i];
while (v != 0) {
ch[v]++;
v = par[v];
}
}
if (uk % 2 == 1)
cout << "-1\n";
else {
int ans = t;
for (int i = 2;i <= n;i++)
ans += (ch[i] % 2 == 0 ? 2 : 1);
cout << ans << '\n';
}
for (int i = 0;i < t;i++) {
int v = a[i];
while (v != 0) {
ch[v]--;
v = par[v];
}
uk -= 1;
if (is[a[i]] && !lf[a[i]]) {
lf[a[i]] = 1;
uk += 1;
}
}
}
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
6748 KB |
Output is correct |
2 |
Incorrect |
81 ms |
8144 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
7 ms |
7512 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
747 ms |
7768 KB |
Output is correct |
2 |
Correct |
753 ms |
8020 KB |
Output is correct |
3 |
Correct |
395 ms |
19484 KB |
Output is correct |
4 |
Execution timed out |
1033 ms |
18520 KB |
Time limit exceeded |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Execution timed out |
1004 ms |
8600 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Execution timed out |
1057 ms |
10688 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Execution timed out |
1036 ms |
12432 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
6748 KB |
Output is correct |
2 |
Incorrect |
81 ms |
8144 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |