Submission #1087726

#	Time	Username	Problem	Language	Result	Execution time	Memory
1087726		Mahog	Bitaro’s Party (JOI18_bitaro)	C++17	100 / 100	507 ms	146132 KiB

bitaro

#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx,avx2,fma")

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

const int MAX = 1e5 + 2;
const int s = 100;
const int oo = -1e9;
int vis[MAX], f[MAX], n, m, q;
vector<int> a[MAX], v;
vector<pair<int, int>> b[MAX];

void solve() {
    cin >> n >> m >> q;
    for (int i = 1; i <= m; i++) {
        int u, v;
        cin >> u >> v;
        a[v].push_back(u);
    }
    fill(vis + 1, vis + n + 1, -1);
    for (int i = 1; i <= n; i++) {
        b[i].push_back({0, i});
        for (auto j : a[i]) {
            for (auto [dist, idx] : b[j]) {
                if (vis[idx] == -1) {
                    vis[idx] = dist + 1;
                    v.push_back(idx);
                } else {
                    vis[idx] = max(vis[idx], dist + 1);
                }
            }
        }
        for (auto j : v) {
            b[i].push_back({vis[j], j});
            vis[j] = -1;
        }
        sort(b[i].begin(), b[i].end(), greater<pair<int, int>>());
        while (b[i].size() > s) b[i].pop_back();
        v.clear();
    }
    /*for (int i = 1; i <= n; i++) {
        for (auto [dist, idx] : b[i]) cout << dist << " " << idx << "\n";
        cout << "\n";
    }*/
    fill(vis + 1, vis + n + 1, 0);
    for (int i = 1; i <= q; i++) {
        int t, y;
        cin >> t >> y;
        for (int j = 1; j <= y; j++) {
            int x;
            cin >> x;
            vis[x] = 1;
            v.push_back(x);
        }
        if (y >= s) {
            fill(f + 1, f + t + 1, -1);
            f[t] = 0;
            int res = -1;
            for (int j = t; j >= 1; j--) {
                if (f[j] == -1) continue;
                for (auto v : a[j]) {
                    f[v] = max(f[v], f[j] + 1);
                }
            }
            for (int j = 1; j <= t; j++) {
                if (!vis[j]) res = max(res, f[j]);
            }
            cout << res << "\n";
        } else {
            int res = -1;
            for (auto [dist, idx] : b[t]) {
                if (!vis[idx]) {
                    res = dist;
                    break;
                }
            }
            cout << res << "\n";
        }
        for (auto j : v) vis[j] = 0;
        v.clear();
    }
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    solve();
}

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 86 / 86