제출 #931464

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
931464		sysia	Spring cleaning (CEOI20_cleaning)	C++17	34 / 100	1059 ms	23388 KiB

cleaning

//Sylwia Sapkowska
#include <bits/stdc++.h>
#pragma GCC optimize("O3", "unroll-loops")
using namespace std;

void __print(int x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << "'" << x << "'";}
void __print(const char *x) {cerr << '"' << x << '"';}
void __print(const string &x) {cerr << '"' << x << '"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ", "; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? ", " : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifdef LOCAL
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif

#define int long long
typedef pair<int, int> T;
const int oo = 1e18, oo2 = 1e9+7, K = 30;
const int mod = 998244353;

void solve(){
    int n, q; cin >> n >> q;
    vector<vector<int>>g(n+1);
    for (int i = 1; i<n; i++){
        int a, b; cin >> a >> b;
        g[a].emplace_back(b);
        g[b].emplace_back(a);
    }
    while (q--){
        int d; cin >> d;
        g.resize(n+d+1);
        int u = n+1;
        vector<int>vt;
        auto fix = [&](){
            for (auto x: vt) g[x].pop_back();
            for (int i = n+1; i<u; i++) g[i].clear();
        };
        while (d--){
            int x; cin >> x;
            vt.emplace_back(x);
            g[x].emplace_back(u);
            g[u].emplace_back(x);
            u++;
        }
        //<u
        int l = 0;
        for (int i = 1; i<u; i++){
            if ((int)g[i].size() == 1){
                l++;
            }
        }
        if (l&1) {
            cout << "-1\n";
            fix();
            continue;
        }
        int ans = 0;
        function<int(int, int)>dfs = [&](int v, int pa){
            int ile = ((int)g[v].size() == 1);
            for (auto x: g[v]){
                if (x == pa) continue;
                ile += dfs(x, v);
            }
            if (v == pa) return 0ll;
            if (ile&1) ans++;
            else ans += 2;
            return ile;
        };
        dfs(1, 1);
        cout << ans << "\n";
        fix();
    }
}

int32_t main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int t = 1;
    //cin >> t;
    while (t--) solve();

    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