Submission #992737

#	Time	Username	Problem	Language	Result	Execution time	Memory
992737		stdfloat	Closing Time (IOI23_closing)	C++17	9 / 100	448 ms	29016 KiB

closing

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

#define ff  first
#define ss  second
#define pii pair<int, int>

using ll = long long;

vector<bool> vis;

vector<ll> c;

vector<vector<pii>> E;

bool dfs(int x, int p = -1, ll sm = 0) {
    bool tr = false;

    if (vis[x]) {
        tr = true;
        c[x] = max(c[x], sm);
    }

    for (auto [i, w] : E[x]) {
        if (i != p && dfs(i, x, sm + w)) {
            tr = true;
            c[x] = max(c[x], sm);
        }
    }

    return tr;
}

int max_score(int n, int X, int Y, long long K, vector<int> U, vector<int> V, vector<int> W) {
    E.assign(n, {});
    for (int i = 0; i < n - 1; i++) {
        E[U[i]].push_back({V[i], W[i]});
        E[V[i]].push_back({U[i], W[i]});
    }

    auto f = [&](int st) -> vector<ll> {
        queue<int> q;
        vector<ll> dis(n, -1);
        q.push(st); dis[st] = 0;
        while (!q.empty()) {
            auto x = q.front(); q.pop();

            for (auto [i, w] : E[x]) {
                if (dis[i] == -1) {
                    dis[i] = dis[x] + w;
                    q.push(i);
                }
            }
        }

        return dis;
    };

    vector<ll> disx = f(X), disy = f(Y);

    vector<pii> u;
    for (int i = 0; i < n; i++)
        u.push_back({min(disx[i], disy[i]), i});

    sort(u.begin(), u.end());

    int mx = 0;
    for (int mk = 0; mk < 1 << n; mk++) {
        c.assign(n, -1);
        vis.assign(n, false);
        for (int i = 0; i < n; i++)
            vis[i] = (mk >> i) & 1;

        dfs(X); dfs(Y);

        ll sm = 0;
        int cnt = 0;
        for (int i = 0; i < n && sm <= K; i++) {
            if (c[i] != -1) {
                sm += c[i];
                cnt += 1 + (c[i] == max(disx[i], disy[i]));
            }
        }

        if (sm > K) continue;

        for (int i = 0; i < n; i++) {
            if (c[u[i].ss] == -1) {
                if ((sm += u[i].ff) > K) break;
                cnt += 1 + (disx[u[i].ss] == disy[u[i].ss]);
            }
        }

        mx = max(mx, cnt);
    }

    return mx;
}

• Subtask 0: 0 / 0
• Subtask 1: 0 / 8
• Subtask 2: 0 / 9
• Subtask 3: 0 / 12
• Subtask 4: 0 / 14
• Subtask 5: 9 / 9
• Subtask 6: 0 / 11
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 17