| # | 제출 시각 | 아이디 | 문제 | 언어 | 결과 | 실행 시간 | 메모리 |
|---|---|---|---|---|---|---|---|
| 1325747 | shirokuma5 | Spring cleaning (CEOI20_cleaning) | C++20 | 0 ms | 0 KiB |
/*# pragma GCC target("avx2")
# pragma GCC optimize("O3")
# pragma GCC optimize("unroll-loops")*/
#include<bits/stdc++.h>
#include<atcoder/all>
using ll = long long;
using namespace std;
using namespace atcoder;
using mint = modint998244353;
const ll mod = 998244353;
const ll INF = 1LL << 60;
const int MAX = 1e9 + 10;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define rep1(i, n) for (int i = 1; i <= (int)(n); i++)
#define rep2(i, l, r) for (int i = (l); i < (int)(r); i++)
#define repd(i, n) for (int i = (int)(n) - 1; i >= 0; i--)
#define repd1(i, n) for (int i = (int)(n); i >= 1; i--)
#define repd2(i, l, r) for (int i = (int)(r) - 1; i >= (int)(l); i--)
template<class T> bool chmin(T &a, T b) {
if (a > b) {
a = b; return 1;
}
return 0;
}
template<class T> bool chmax(T &a, T b) {
if (a < b) {
a = b; return 1;
}
return 0;
}
struct edge {
int to, w;
};
ll inv(ll a) {
ll b = mod, u = 1, v = 0;
while(b) {
ll t = a / b;
a -= b * t;
swap(a, b);
u -= v * t;
swap(u, v);
}
u %= mod;
if (u < 0) u += mod;
return u;
}
template<class T> void print(vector<T> a) {
int n = a.size();
for (int i = 0; i < n; i++) cout << a[i] << " ";
cout << endl;
}
template<class T> int low_idx(const vector<T> &a, T x) {
return distance(a.begin(), lower_bound(a.begin(), a.end(), x));
}
template<class T> bool next_combination(T &bit, int N) {
T x = bit & -bit, y = bit + x;
bit = (((bit & ~y) / x) >> 1) | y;
return (bit < (1LL << N));
}
int next_combination(int sub) {
int x = sub & -sub, y = sub + x;
return (((sub & ~y) / x) >> 1) | y;
}
vector<vector<int>> G;
vector<int> par;
void dfs(int now, int pre = -1) {
for (int nex : G[now]) {
if (nex == pre) continue;
par[nex] = now; dfs(nex, now);
}
}
int main() {
ios::sync_with_stdio(false);
std::cin.tie(nullptr);
int n, q; cin >> n >> q;
par.assign(n + 1, -1);
G.resize(n + 1);
rep(i, n-1) {
int u, v; cin >> u >> v;
G[u].push_back(v); G[v].push_back(u);
}
int r = 1;
vector<int> deg(n + 1), seen(n + 1, 0);
vector<int> sorted;
queue<int> todo;
rep1(i, n) {
deg[i] = G[i].size();
if (deg[i] == 1) todo.push(i);
}
while (!todo.empty()) {
r = todo.front(); todo.pop(); seen[r] = 1;
sorted.push_back(r);
for (int nex : G[r]) {
if (seen[nex] == 1) par[nex] = r;
else if (--deg[nex] == 1) todo.push(nex);
}
}
while (q--) {
int d; cin >> d;
vector<int> a(d);
rep(i, d) cin >> a[i];
ll res = 0;
vector<int> chi(n + 1, 0);
rep(i, d) {
chi[a[i]]++; res++;
}
rep1(i, n) if (chi[i] == 0 && G[i].size() == 1) {
chi[i] = 1;
}
for (int v : sorted) {
if (par[v] == -1) {
if (chi[v] % 2 == 1) res = -1;
}
else {
if (chi[v] % 2 == 0) chi[v] = 2;
else chi[v] = 1;
res += chi[v]; chi[par[v]] += chi[v];
}
}
cout << res << endl;
}
}
