Submission #751004

#	Time	Username	Problem	Language	Result	Execution time	Memory
751004		inventiontime	Spring cleaning (CEOI20_cleaning)	C++17	16 / 100	1079 ms	13992 KiB

cleaning

#include <bits/stdc++.h>
using namespace std;

#define int ll
#define endl '\n' //comment for interactive
#define fast_io ios::sync_with_stdio(0); cin.tie(0); cout.tie(0)

#define pb push_back
#define re resize
#define ff first
#define ss second

#define all(x) (x).begin(), (x).end()
#define all1(x) (x).begin()+1, (x).end()
#define loop(i, n) for(int i = 0; i < n; i++)
#define loop1(i, n) for(int i = 1; i <= n; i++)

#define print(x) cout << #x << ": " << x << endl << flush

typedef long long ll;
typedef vector<int> vi;
typedef array<int, 2> ii;
typedef array<int, 3> ti;
typedef vector<ii> vii;
typedef vector<ti> vti;
typedef vector<vi> vvi;
typedef priority_queue<int> pq;

template<class T> bool ckmin(T&a, T b) { bool B = a > b; a = min(a, b); return B; }
template<class T> bool ckmax(T&a, T b) { bool B = a < b; a = max(a, b); return B; }

const int inf = 1e17;
const int maxn = 1e5+5;

vi adj[maxn];

void solve() {

    int n, q;
    cin >> n >> q;
    loop1(i, n-1) {
        int u, v;
        cin >> u >> v;
        adj[u].pb(v);
        adj[v].pb(u);
    }

    while(q--) {
        int d; cin >> d;
        vi a(d+1);
        loop1(i, d) cin >> a[i];
        loop1(i, d) {
            adj[a[i]].pb(n+i);
            adj[n+i].pb(a[i]);
        }

        vi lv(n+d+1);
        int res = 0;
        auto dfs = [&] (int u, int p, auto dfs) -> void {
            for(auto v : adj[u]) if(v != p) {
                dfs(v, u, dfs);
                lv[u] += lv[v];
            }
            if(adj[u].size() == 1) lv[u] += 1;
            if(u != p) res += 1 + !(lv[u] & 1);
        };
        dfs(1, 1, dfs);

        if(lv[1] & 1) cout << -1 << endl;
        else cout << res << endl;

        loop1(i, d) {
            adj[a[i]].pop_back();
            adj[n+i].pop_back();
        }
    }

}

signed main() {

    fast_io;

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

    return 0;

}

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