#include <bits/stdc++.h>
using namespace std;
const int MAX_N = 1e5;
int leafs[MAX_N + 1], parent[MAX_N + 1], a[MAX_N + 1];
vector<int> adj[MAX_N + 1];
int ans;
void dfs( int u, int p ) {
parent[u] = p;
leafs[u] = (adj[u].size() == 1);
for ( int v: adj[u] ) {
if ( v == p )
continue;
dfs( v, u );
leafs[u] += leafs[v];
}
ans += 2 - leafs[u] % 2;
}
int main() {
int n, q;
cin >> n >> q;
for ( int i = 0; i < n - 1; i++ ) {
int u, v;
cin >> u >> v;
adj[u].push_back( v );
adj[v].push_back( u );
}
int r = 1;
while ( adj[r].size() == 1 )
r++;
ans = 0;
dfs( r, 0 );
for ( int i = 0; i < q; i++ ) {
int d;
int change = 0;
cin >> d;
for ( int i = 0; i < d; i++ ) {
cin >> a[i];
int v = a[i];
change++;
if ( adj[v].size() == 1 )
continue;
while ( v != 0 ) {
change -= 2 - leafs[v] % 2;
leafs[v]++;
change += 2 - leafs[v] % 2;
v = parent[v];
}
}
change -= 2 - leafs[r] % 2;
cout << (leafs[r] % 2 == 0 ? ans + change : -1) << "\n";
for ( int i = 0; i < d; i++ ) {
int v = a[i];
if ( adj[v].size() == 1 )
continue;
while ( v != 0 ) {
leafs[v]--;
v = parent[v];
}
}
}
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
2652 KB |
Output is correct |
2 |
Incorrect |
44 ms |
4352 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
15 ms |
3420 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
891 ms |
4128 KB |
Output is correct |
2 |
Correct |
836 ms |
4180 KB |
Output is correct |
3 |
Correct |
482 ms |
15156 KB |
Output is correct |
4 |
Execution timed out |
1060 ms |
14204 KB |
Time limit exceeded |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Execution timed out |
1101 ms |
4604 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
139 ms |
6480 KB |
Output is correct |
2 |
Incorrect |
69 ms |
6300 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
220 ms |
8636 KB |
Output is correct |
2 |
Execution timed out |
1047 ms |
10400 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
2652 KB |
Output is correct |
2 |
Incorrect |
44 ms |
4352 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |