Submission #1124966

#	Time	Username	Problem	Language	Result	Execution time	Memory
1124966		LaMatematica14	Bitaro’s Party (JOI18_bitaro)	C++20	0 / 100	6 ms	840 KiB

bitaro

#include <bits/stdc++.h>
using namespace std;
const int lim = 10000000;
const int rad = 400;
int N;
vector<vector<int>> adj;
vector<vector<pair<int, int>>> dp;

void crea(int a) {
    priority_queue<pair<int, int>> pq;
    unordered_set<int> pr;
    int dc = adj[a].size();
    vector<int> id(dc, 0);
    bool ff = 1;
    int h = 0;
    while (h < rad) {
        int best = -1, idb = -1;
        for (int i = 0; i < dc; i++) {
            while (id[i] < dp[adj[a][i]].size() && pr.count(dp[adj[a][i]][id[i]].second)) id[i]++;
            if (id[i] >= dp[adj[a][i]].size()) continue;
            if (dp[adj[a][i]][id[i]].first > best) {
                idb = i;
                best = dp[adj[a][i]][id[i]].first; 
            }
        }
        if (idb < 0) {
            ff = 0; break;
        }
        pr.insert(dp[adj[a][idb]][id[idb]].second);
        dp[a].push_back(dp[adj[a][idb]][id[idb]]);
        dp[a][h++].first++;
        id[idb]++;
    }
    if (h < rad) dp[a].push_back({0, a});
}

int bfs(int a, unordered_set<int> skip) {
    queue<int> n; vector<int> dist(N, lim);
    dist[a] = 0; n.push(a);
    int m = -1;
    while (!n.empty()) {
        a = n.front(); n.pop();
        if (!skip.count(a)) m = max(m, dist[a]);
        for (int x : adj[a]) {
            if (dist[x] < lim) continue;
            dist[x] = dist[a]+1;
            n.push(x);
        }
    }
    return m;
}

int prec(int a, unordered_set<int> s) {
    int m = -1;
    for (int i = 0; i < dp[a].size(); i++) {
        if (s.count(dp[a][i].second)) continue;
        m = max(m, dp[a][i].first);
    }
    return m;
}


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

    int M, Q; cin >> N >> M >> Q;
    adj.resize(N+1); dp.resize(N+1);
    for (int i = 0; i < M; i++) {
        int s, t; cin >> s >> t;
        adj[t].push_back(s);
    }
    
    for (int i = 1; i <= N; i++) crea(i);

    for (int i = 0; i < Q; i++) {
        unordered_set<int> s;
        int a, y; cin >> a >> y;
        for (int j = 0; j < y; j++) {int aus; cin >> aus; s.insert(aus);}

        if (y >= rad) cout << bfs(a, s) << "\n";
        else cout << prec(a, s) << "\n";
    }
}

• Subtask 1: 0 / 7
• Subtask 2: 0 / 7
• Subtask 3: 0 / 86