Submission #574396

#	Time	Username	Problem	Language	Result	Execution time	Memory
574396		piOOE	Spring cleaning (CEOI20_cleaning)	C++17	34 / 100	1095 ms	21272 KiB

cleaning

#include <bits/stdc++.h>

using namespace std;

#define sz(x) ((int)size(x))
#define all(x) begin(x), end(x)
#define trace(x) cout << #x << ": " << (x) << endl;

typedef long long ll;

mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());

int rand(int l, int r) { return (int) ((ll) rnd() % (r - l + 1)) + l; }

const int N = 100000, infI = 1e9 + 7;
const ll infL = 3e18;

vector<int> g[N * 2];
ll dp[3][N * 2]; //LL???

void dfs(int v, int p) {
    dp[0][v] = 0;
    dp[1][v] = dp[2][v] = infL;
    if (sz(g[v]) <= 1) {
        //v is a leaf
        dp[1][v] = 1;
    } else {
        for (int to: g[v]) {
            if (to != p) {
                dfs(to, v);
                array<ll, 3> dq = {dp[0][v], dp[1][v], dp[2][v]};
                dp[0][v] = min({dq[2] + dp[2][to], dq[1] + dp[1][to]});
                dp[1][v] = min({dq[0] + dp[1][to], dq[2] + dp[1][to], dq[1] + dp[2][to]});
                dp[2][v] = min({dq[0] + dp[2][to], dq[2] + dp[2][to], dq[1] + dp[1][to]});
            }
        }
        dp[1][v] += 1;
        dp[2][v] += 2;
    }
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, q;
    cin >> n >> q;
    int root = -1;
    for (int i = 0; i < n - 1; ++i) {
        int a, b;
        cin >> a >> b;
        --a, --b;
        g[a].push_back(b);
        g[b].push_back(a);
    }
    for (int i = 0; i < n; ++i) {
        if (sz(g[i]) > 1) {
            root = i;
            break;
        }
    }
    assert(root != -1);
    while (q--) {
        int D;
        cin >> D;
        vector<int> a(D);
        for (int i = 0; i < D; ++i) {
            cin >> a[i];
            --a[i];
            g[a[i]].push_back(i + n);
        }
        dfs(root, -1);
        cout << (dp[0][root] >= infL ? -1 : dp[0][root]) << '\n';
        for (int i = 0; i < D; ++i) {
            g[a[i]].pop_back();
        }
    }
    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