제출 #1141107

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1141107		OI_Account	Spring cleaning (CEOI20_cleaning)	C++20	34 / 100	1096 ms	18760 KiB

cleaning

#pragma GCC optimize("O2,unroll-loops,Ofast")
#include <bits/stdc++.h>
using namespace std;

const int N = 200'000;

int n, q, d, deg[N + 10];
int sz[N + 10], ans;
vector<int> adj[N + 10];

void readInput() {
    cin >> n >> q;
    for (int i = 1; i < n; i++) {
        int u, v;
        cin >> u >> v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    for (int i = 1; i <= n; i++)
        deg[i] = adj[i].size();
}

void dfs(int u = 1, int par = 0) {
    sz[u] = (adj[u].size() == 1);
    for (auto v: adj[u])
        if (v != par) {
            dfs(v, u);
            sz[u] += sz[v];
        }
    if (par)
        ans += 1 + (sz[u] % 2 == 0);
}

void query() {
    cin >> d;
    for (int i = 1; i <= d; i++) {
        int u = n + i, v;
        cin >> v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    int all = 0;
    for (int i = 1; i <= n + d; i++)
        if (adj[i].size() == 1)
            all++;
    if (all % 2)
        cout << -1 << '\n';
    else {
        ans = 0;
        dfs();
        cout << ans << '\n';
    }
    for (int i = 1; i <= n; i++)
        while (deg[i] != adj[i].size()) {
            int v = adj[i].back();
            adj[i].pop_back();
            adj[v].pop_back();
        }
}

void solveSub4() {
    while (q--)
        query();
    cout.flush();
}

int main() {
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    readInput();
    solveSub4();
    return 0;
}

• Subtask 1: 0 / 0
• Subtask 2: 9 / 9
• Subtask 3: 9 / 9
• Subtask 4: 16 / 16
• Subtask 5: 0 / 19
• Subtask 6: 0 / 17
• Subtask 7: 0 / 30