#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;
#define long unsigned long
#define pb push_back
#define mp make_pair
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define lb lower_bound
#define ub upper_bound
#define sz(v) int((v).size())
#define do_not_disturb ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define endl '\n'
const int N = 2e5+7;
vector <vector <int>> graph(N), new_graph(N);
int root, subtree[N], depth[N], parent[N], nw[N];
ll ans;
void dfs(int v, int p) {
subtree[v] = (sz(new_graph[v]) == 1 ? 1 : 0);
parent[v] = p;
for (auto to : new_graph[v]) {
if (to == p) {
continue;
}
depth[to] = depth[v] + 1;
dfs(to, v);
subtree[v] += subtree[to];
}
ans += 2 - (subtree[v] % 2);
}
int get(int n) {
ans = 0;
for (int i = 1; i <= n; i++) {
if (sz(new_graph[i]) > 1) {
root = i;
}
}
dfs(root, root);
if (subtree[root]&1) return -1;
else return ans-2;
}
void subtask5(int n, int q) {
for (int i = 1; i <= n; i++) {
new_graph[i].clear();
for (auto to : graph[i]) new_graph[i].pb(to);
}
dfs(1, 1);
auto res = ans-2;
int l = int(log2(n))+1;
if (n != (1 << l) - 1) return;
int mn = 2e9, mx = -2e9;
for (int i = 1; i <= n; i++) {
if (sz(graph[i]) == 1) {
mn = min(mn, depth[i]);
mx = max(mx, depth[i]);
}
}
if (mx != mn) return;
while (q--) {
int k;
cin >> k;
res += k;
vector <int> D(k);
for (auto &to : D) cin >> to;
for (auto to : D) {
auto x = to;
if (sz(graph[x]) == 1) {
nw[x]++;
}
if (sz(graph[x]) == 1 && nw[x] == 1) continue;
while (x != parent[x]) {
subtree[x]++;
if (subtree[x]&1) res--;
else res++;
x = parent[x];
}
subtree[1]++;
}
if (subtree[1]&1) cout << -1 << endl;
else cout << res << endl;
for (auto to : D) {
auto x = to;
if (sz(graph[x]) == 1) {
nw[x]--;
}
if (sz(graph[x]) == 1 && nw[x] == 0) continue;
while (x != parent[x]) {
if (subtree[x]&1) res++;
else res--;
subtree[x]--;
x = parent[x];
}
subtree[1]--;
}
res -= k;
}
exit(0);
}
void solve() {
int n, q;
cin >> n >> q;
for (int i = 1; i < n; i++) {
int a, b;
cin >> a >> b;
graph[a].pb(b);
graph[b].pb(a);
}
subtask5(n, q);
if (n <= 20000 && q <= 300) {
while (q--) {
int vertex = n+1;
int k;
cin >> k;
for (int i = 1; i <= n+k; i++) {
new_graph[i].clear();
for (auto to : graph[i]) new_graph[i].pb(to);
}
while (k--) {
int x;
cin >> x;
new_graph[x].pb(vertex);
new_graph[vertex].pb(x);
vertex++;
}
cout << get(vertex-1) << endl;
}
}
else {
for (int i = 1; i <= n; i++) {
new_graph[i].clear();
for (auto to : graph[i]) new_graph[i].pb(to);
}
dfs(1, 1);
ans -= 2;
if (sz(graph[1]) > 1) {
while (q--) {
int k;
cin >> k;
ans += k;
while (k--) {
int x;
cin >> x;
}
if (subtree[1]&1) {
if (k&1) cout << ans << endl;
else cout << -1 << endl;
}
else if (k&1) cout << -1 << endl;
else cout << ans << endl;
ans -= k;
}
}
else {
while (q--) {
int k;
cin >> k;
while (k--) {
int x;
cin >> x;
}
k--;
ans += k;
if (subtree[1]&1) {
if (k&1) cout << ans << endl;
else cout << -1 << endl;
}
else if (k&1) cout << -1 << endl;
else cout << ans << endl;
ans -= k;
}
}
}
}
int main() {
do_not_disturb
int t = 1;
//~ cin >> t;
while (t--) {
solve();
}
return 0;
}
/*
7 5
1 2
1 3
2 4
2 5
3 6
3 7
1 1
2 1 1
2 7 7
2 6 7
2 4 7
*/
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
5 ms |
9684 KB |
Output is correct |
| 2 |
Incorrect |
21 ms |
11280 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
29 ms |
13904 KB |
Output is correct |
| 2 |
Correct |
23 ms |
13888 KB |
Output is correct |
| 3 |
Incorrect |
47 ms |
17840 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
23 ms |
14448 KB |
Output is correct |
| 2 |
Correct |
22 ms |
14420 KB |
Output is correct |
| 3 |
Incorrect |
50 ms |
24760 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
344 ms |
11968 KB |
Output is correct |
| 2 |
Correct |
219 ms |
11468 KB |
Output is correct |
| 3 |
Correct |
316 ms |
11260 KB |
Output is correct |
| 4 |
Correct |
347 ms |
11732 KB |
Output is correct |
| 5 |
Correct |
310 ms |
11948 KB |
Output is correct |
| 6 |
Correct |
373 ms |
11980 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
56 ms |
15052 KB |
Output is correct |
| 2 |
Correct |
63 ms |
14900 KB |
Output is correct |
| 3 |
Correct |
46 ms |
12324 KB |
Output is correct |
| 4 |
Correct |
52 ms |
14884 KB |
Output is correct |
| 5 |
Correct |
53 ms |
14816 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
77 ms |
18048 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
5 ms |
9684 KB |
Output is correct |
| 2 |
Incorrect |
21 ms |
11280 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
